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Allmendinger F, Scheuren PS, De Schoenmacker I, Brunner F, Rosner J, Curt A, Hubli M. Contact-Heat Evoked Potentials: Insights into Pain Processing in CRPS Type I. J Pain Res 2024; 17:989-1003. [PMID: 38505501 PMCID: PMC10949273 DOI: 10.2147/jpr.s436645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 02/23/2024] [Indexed: 03/21/2024] Open
Abstract
Purpose The pathophysiological mechanisms underlying the development of chronic pain in complex regional pain syndrome (CRPS) are diverse and involve both peripheral and central changes in pain processing, such as sensitization of the nociceptive system. The aim of this study was to objectively distinguish the specific changes occurring at both peripheral and central levels in nociceptive processing in individuals with chronic CRPS type I. Patients and Methods Nineteen individuals with chronic CRPS type I and 16 age- and sex-matched healthy controls (HC) were recruited. All individuals underwent a clinical examination and pain assessment in the most painful limb, the contralateral limb, and a pain-free control area to distinguish between peripheral and central mechanisms. Contact-heat evoked potentials (CHEPs) were recorded after heat stimulation of the three different areas and amplitudes and latencies were analyzed. Additionally, quantitative sensory testing (QST) was performed in all three areas. Results Compared to HC, CHEP amplitudes in CRPS were only increased after stimulation of the painful area (p=0.025), while no increases were observed for the pain-free control area (p=0.14). None of the CHEP latencies were different between the two cohorts (all p>0.23). Furthermore, individuals with CRPS showed higher pain ratings after stimulation of the painful limb compared to their contralateral limb (p=0.013). Lastly, compared to HC, mechanical (p=0.012) and thermal (p=0.046) sensitivity was higher in the painful area of the CRPS cohort. Conclusion This study provides neurophysiological evidence supporting an intact thermo-nociceptive pathway with signs of peripheral sensitization, such as hyperexcitable primary afferent nociceptors, in individuals with CRPS type I. This is further supported by the observation of mechanical and thermal gain of sensation only in the painful limb. Additionally, the increased CHEP amplitudes might be related to fear-induced alterations of nociceptive processing.
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Affiliation(s)
- Florin Allmendinger
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Paulina Simonne Scheuren
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
- Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
- International Collaboration on Repair Discoveries, Vancouver, BC, Canada
- Department of Anesthesiology, Pharmacology & Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Iara De Schoenmacker
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Florian Brunner
- Department of Physical Medicine and Rheumatology, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
- Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
- Danish Pain Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Armin Curt
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Michèle Hubli
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
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Mylius V, Moisset X, Rukavina K, Rosner J, Korwisi B, Marques A, Lloret SP, Kägi G, Bohlhalter S, Bannister K, Chaudhuri KR, Barke A, Tinazzi M, Brefel-Courbon C, Treede RD, de Andrade DC. New ICD-11 diagnostic criteria for chronic secondary musculoskeletal pain associated with Parkinson disease. Pain 2024:00006396-990000000-00497. [PMID: 38227568 DOI: 10.1097/j.pain.0000000000003138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 10/10/2023] [Indexed: 01/18/2024]
Affiliation(s)
- Veit Mylius
- Department of Neurology, Center for Neurorehabilitation, Valens, Switzerland
- Department of Neurology, Philipps University, Marburg, Germany
- Department of Neurology, Cantonal Hospital St. Gallen, St. Gallen, Switzerland
| | - Xavier Moisset
- Université Clermont Auvergne, CHU de Clermont-Ferrand, Inserm, Neuro-Dol, Clermont-Ferrand, France
| | - Katarina Rukavina
- Division of Neuroscience, Department of Basic & Clinical Neuroscience, King's College London, Institute of Psychiatry, Psychology & Neuroscience, London, United Kingdom
- Parkinson Foundation Centre of Excellence in Care and Research, King's College Hospital NHS Foundation Trust, London, United Kingdom
| | - Jan Rosner
- Danish Pain Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
- Department of Neurology, Inselspital, Bern University Hospital, and University of Bern, Bern, Switzerland
| | - Beatrice Korwisi
- Division of Clinical Psychology and Psychological Interventions, Institute of Psychology, University Duisburg-Essen, Essen, Germany
| | - Ana Marques
- Université Clermont Auvergne, CHU de Clermont-Ferrand, Inserm, Neuro-Dol, Clermont-Ferrand, France
| | - Santiago Perez Lloret
- Facultad de Medicina, Pontificia Universidad Católica Argentina, Buenos Aires, Argentina
- Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
- Observatorio de Salud Pública, Universidad Católica Argentina, Consejo de Investigaciones Científicas y Técnicas (UCA-CONICET), Buenos Aires, Argentina
| | - Georg Kägi
- Department of Neurology, Cantonal Hospital St. Gallen, St. Gallen, Switzerland
- Department of Neurology, Inselspital, Bern University Hospital, and University of Bern, Bern, Switzerland
| | - Stephan Bohlhalter
- Neurocenter, Luzerner Kantonsspital, Lucerne, Switzerland
- Department of Neurology, University of Zurich, Zurich, Switzerland
| | - Kirsty Bannister
- Division of Neuroscience, Department of Basic & Clinical Neuroscience, King's College London, Institute of Psychiatry, Psychology & Neuroscience, London, United Kingdom
| | - Kallol Ray Chaudhuri
- Division of Neuroscience, Department of Basic & Clinical Neuroscience, King's College London, Institute of Psychiatry, Psychology & Neuroscience, London, United Kingdom
- Parkinson Foundation Centre of Excellence in Care and Research, King's College Hospital NHS Foundation Trust, London, United Kingdom
| | - Antonia Barke
- Division of Clinical Psychology and Psychological Interventions, Institute of Psychology, University Duisburg-Essen, Essen, Germany
| | - Michele Tinazzi
- Department of Neurosciences, Biomedicine and Movement, University of Verona, Verona, Italy
| | - Christine Brefel-Courbon
- Department of Clinical Pharmacology and Neurosciences, University Hospital of Toulouse, Inserm, Toulouse, France
| | - Rolf Detlef Treede
- Department of Neurophysiology, Mannheim Center for Translational Neurosciences, and Department of Psychiatry and Psychotherapy, Central Institute for Mental Health, Heidelberg University, Mannheim, Germany
| | - Daniel Ciampi de Andrade
- Center for Neuroplasticity and Pain (CNAP), Department of Health Science and Technology, Faculty of Medicine, Aalborg University, Aalborg, Denmark
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Dimitriou D, Meisterhans M, Geissmann M, Borpas P, Hoch A, Rosner J, Schubert M, Aguirre J, Eichenberger U, Zingg PO. The effect of experimentally induced gluteal muscle weakness on joint kinematics, reaction forces, and dynamic balance performance during deep bilateral squats. J Orthop Res 2024; 42:164-171. [PMID: 37309814 DOI: 10.1002/jor.25644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 05/19/2023] [Accepted: 05/26/2023] [Indexed: 06/14/2023]
Abstract
Squatting is a common daily activity and fundamental exercise in resistance training and closed kinetic chain programs. The aim of this study was to investigate the effects of an experimentally induced weakness of the gluteal muscles on joint kinematics, reactions forces (JRFs), and dynamic balance performance during deep bilateral squats in healthy young adults. Ten healthy adults received sequential blocks of (1) branch of the superior gluteal nerve to the tensor fasciae latae (SGNtfl) muscle, (2) superior gluteal nerve (SGN), and (3) inferior gluteal nerve (IGN) on the dominant right leg. At the control condition and following each block, the participants were instructed to perform deep bilateral squats standing on two force plates. Hip, knee, ankle, and pelvis kinematics did not differ significantly following iatrogenic weakness of gluteal muscles. The most important finding was the significant differences in JRFs following SGN and IGN block, with the affected hip, patellofemoral, and ankle joint demonstrating lower JRFs, whereas the contralateral joints demonstrated significantly higher JRFs, especially the patellofemoral joint which demonstrated an average maximum difference of 1.43 x body weight compared with the control condition. When performing a deep bilateral leg squat under SGN and IGN block, the subjects demonstrated an increased center of pressure (CoP) range and standard deviation (SD) in mediolateral compared with the control condition. These results imply that squat performance changes significantly following weakness of gluteal muscles and should be considered when assessing and training athletes or patients with these injuries.
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Affiliation(s)
- Dimitris Dimitriou
- Department of Orthopedics, University Hospital Balgrist, Zurich, Switzerland
| | - Michel Meisterhans
- Department of Orthopedics, University Hospital Balgrist, Zurich, Switzerland
| | - Marina Geissmann
- Swiss Center for Movement Analysis, Balgrist Campus AG, Zurich, Switzerland
| | - Paul Borpas
- Department of Orthopedics, University Hospital Balgrist, Zurich, Switzerland
| | - Armando Hoch
- Department of Orthopedics, University Hospital Balgrist, Zurich, Switzerland
| | - Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Martin Schubert
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - José Aguirre
- Balgrist University Hospital, Department of Anesthesiology, Intensive Care and Pain Medicine, Balgrist University Hospital, Zurich, Switzerland
| | - Urs Eichenberger
- Balgrist University Hospital, Department of Anesthesiology, Intensive Care and Pain Medicine, Balgrist University Hospital, Zurich, Switzerland
| | - Patrick O Zingg
- Department of Orthopedics, University Hospital Balgrist, Zurich, Switzerland
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Rosner J, de Andrade DC, Davis KD, Gustin SM, Kramer JLK, Seal RP, Finnerup NB. Central neuropathic pain. Nat Rev Dis Primers 2023; 9:73. [PMID: 38129427 DOI: 10.1038/s41572-023-00484-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/21/2023] [Indexed: 12/23/2023]
Abstract
Central neuropathic pain arises from a lesion or disease of the central somatosensory nervous system such as brain injury, spinal cord injury, stroke, multiple sclerosis or related neuroinflammatory conditions. The incidence of central neuropathic pain differs based on its underlying cause. Individuals with spinal cord injury are at the highest risk; however, central post-stroke pain is the most prevalent form of central neuropathic pain worldwide. The mechanisms that underlie central neuropathic pain are not fully understood, but the pathophysiology likely involves intricate interactions and maladaptive plasticity within spinal circuits and brain circuits associated with nociception and antinociception coupled with neuronal hyperexcitability. Modulation of neuronal activity, neuron-glia and neuro-immune interactions and targeting pain-related alterations in brain connectivity, represent potential therapeutic approaches. Current evidence-based pharmacological treatments include antidepressants and gabapentinoids as first-line options. Non-pharmacological pain management options include self-management strategies, exercise and neuromodulation. A comprehensive pain history and clinical examination form the foundation of central neuropathic pain classification, identification of potential risk factors and stratification of patients for clinical trials. Advanced neurophysiological and neuroimaging techniques hold promise to improve the understanding of mechanisms that underlie central neuropathic pain and as predictive biomarkers of treatment outcome.
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Affiliation(s)
- Jan Rosner
- Danish Pain Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
- Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Daniel C de Andrade
- Center for Neuroplasticity and Pain (CNAP), Department of Health Science and Technology, Faculty of Medicine, Aalborg University, Aalborg, Denmark
| | - Karen D Davis
- Division of Brain, Imaging and Behaviour, Krembil Brain Institute, Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada
- Department of Surgery and Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Sylvia M Gustin
- Centre for Pain IMPACT, Neuroscience Research Australia, Sydney, New South Wales, Australia
- NeuroRecovery Research Hub, School of Psychology, University of New South Wales, Sydney, New South Wales, Australia
| | - John L K Kramer
- International Collaboration on Repair Discoveries, ICORD, University of British Columbia, Vancouver, Canada
- Department of Anaesthesiology, Pharmacology & Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, Canada
| | - Rebecca P Seal
- Pittsburgh Center for Pain Research, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Departments of Neurobiology and Otolaryngology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Nanna B Finnerup
- Danish Pain Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.
- Department of Neurology, Aarhus University Hospital, Aarhus, Denmark.
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De Schoenmacker I, Sirucek L, Scheuren PS, Lütolf R, Gorrell LM, Brunner F, Curt A, Rosner J, Schweinhardt P, Hubli M. Sensory phenotypes in complex regional pain syndrome and chronic low back pain-indication of common underlying pathomechanisms. Pain Rep 2023; 8:e1110. [PMID: 38027464 PMCID: PMC10653599 DOI: 10.1097/pr9.0000000000001110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 08/24/2023] [Accepted: 08/29/2023] [Indexed: 12/01/2023] Open
Abstract
Introduction First-line pain treatment is unsatisfactory in more than 50% of chronic pain patients, likely because of the heterogeneity of mechanisms underlying pain chronification. Objectives This cross-sectional study aimed to better understand pathomechanisms across different chronic pain cohorts, regardless of their diagnoses, by identifying distinct sensory phenotypes through a cluster analysis. Methods We recruited 81 chronic pain patients and 63 age-matched and sex-matched healthy controls (HC). Two distinct chronic pain cohorts were recruited, ie, complex regional pain syndrome (N = 20) and low back pain (N = 61). Quantitative sensory testing (QST) was performed in the most painful body area to investigate somatosensory changes related to clinical pain. Furthermore, QST was conducted in a pain-free area to identify remote sensory alterations, indicating more widespread changes in somatosensory processing. Results Two clusters were identified based on the QST measures in the painful area, which did not represent the 2 distinct pain diagnoses but contained patients from both cohorts. Cluster 1 showed increased pain sensitivities in the painful and control area, indicating central sensitization as a potential pathomechanism. Cluster 2 showed a similar sensory profile as HC in both tested areas. Hence, either QST was not sensitive enough and more objective measures are needed to detect sensitization within the nociceptive neuraxis or cluster 2 may not have pain primarily because of sensitization, but other factors such as psychosocial ones are involved. Conclusion These findings support the notion of shared pathomechanisms irrespective of the pain diagnosis. Conversely, different mechanisms might contribute to the pain of patients with the same diagnosis.
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Affiliation(s)
- Iara De Schoenmacker
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
- Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland
| | - Laura Sirucek
- Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland
- Department of Chiropractic Medicine, Integrative Spinal Research Group, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Paulina S. Scheuren
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
- Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Robin Lütolf
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Lindsay M. Gorrell
- Department of Chiropractic Medicine, Integrative Spinal Research Group, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Florian Brunner
- Physical Medicine and Rheumatology, Balgrist University Hospital, Zurich, Switzerland
| | - Armin Curt
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
- Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
- Danish Pain Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Petra Schweinhardt
- Department of Chiropractic Medicine, Integrative Spinal Research Group, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
- Alan Edward Center for Research on Pain, McGill University, Montreal, QC, Canada
| | - Michèle Hubli
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
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Nowacki A, Zhang D, Barlatey S, Ai-Schläppi J, Rosner J, Arnold M, Pollo C. Deep Brain Stimulation of the Central Lateral and Ventral Posterior Thalamus for Central Poststroke Pain Syndrome: Preliminary Experience. Neuromodulation 2023; 26:1747-1756. [PMID: 36266180 DOI: 10.1016/j.neurom.2022.09.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 09/02/2022] [Accepted: 09/13/2022] [Indexed: 11/07/2022]
Abstract
OBJECTIVE The beneficial effects of thalamic deep brain stimulation (DBS) at various target sites in treating chronic central neuropathic pain (CPSP) remain unclear. This study aimed to evaluate the effectiveness of DBS at a previously untested target site in the central lateral (CL) thalamus, together with classical sensory thalamic stimulation (ventral posterior [VP] complex). MATERIALS AND METHODS We performed a monocentric retrospective study of a consecutive series of six patients with CPSP who underwent combined DBS lead implantation of the CL and VP. Patient-reported outcome measures were recorded before and after surgery using the numeric rating scale (NRS), short-form McGill pain questionnaire (sf-MPQ), EuroQol 5-D quality-of-life questionnaire, and Beck Depression Inventory. DBS leads were reconstructed and projected onto a three-dimensional stereotactic atlas. RESULTS NRS-but not sf-MPQ-rated pain intensity-was significantly reduced throughout the follow-up period of 12 months compared with baseline (p = 0.005, and p = 0.06 respectively, Friedman test). At the last available follow-up (12 to 30 months), three patients described a more than 50% reduction. Two of the three long-term responders were stimulated in the CL (1000 Hz, 90 μs, 3.5-5.0 mA), whereas the third preferred VP complex stimulation (50 Hz, 200 μs, 0.7-1.2 mA). No persistent procedure- or stimulation-associated side effects were noted. CONCLUSIONS These preliminary findings suggest that DBS of the CL might constitute a promising alternative target in cases in which classical VP complex stimulation does not yield satisfactory postoperative pain reduction. The results need to be confirmed in larger, prospective series of patients.
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Affiliation(s)
- Andreas Nowacki
- Department of Neurosurgery, Inselspital, Bern University Hospital, University Bern, Bern, Switzerland.
| | - David Zhang
- Department of Neurosurgery, Inselspital, Bern University Hospital, University Bern, Bern, Switzerland
| | - Sabry Barlatey
- Department of Neurosurgery, Inselspital, Bern University Hospital, University Bern, Bern, Switzerland
| | - Janine Ai-Schläppi
- Department of Neurosurgery, Inselspital, Bern University Hospital, University Bern, Bern, Switzerland
| | - Jan Rosner
- Department of Neurology, Inselspital, Bern University Hospital, University Bern, Bern, Switzerland; Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Marcel Arnold
- Department of Neurology, Inselspital, Bern University Hospital, University Bern, Bern, Switzerland
| | - Claudio Pollo
- Department of Neurosurgery, Inselspital, Bern University Hospital, University Bern, Bern, Switzerland
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Pfender N, Rosner J, Zipser CM, Friedl S, Schubert M, Sutter R, Klarhoefer M, Spirig JM, Betz M, Freund P, Farshad M, Curt A, Hupp M. Increased cranio-caudal spinal cord oscillations are the cardinal pathophysiological change in degenerative cervical myelopathy. Front Neurol 2023; 14:1217526. [PMID: 38020663 PMCID: PMC10663304 DOI: 10.3389/fneur.2023.1217526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 10/16/2023] [Indexed: 12/01/2023] Open
Abstract
Introduction Degenerative cervical myelopathy (DCM) is the most common cause of non-traumatic incomplete spinal cord injury, but its pathophysiology is poorly understood. As spinal cord compression observed in standard MRI often fails to explain a patient's status, new diagnostic techniques to assess DCM are one of the research priorities. Minor cardiac-related cranio-caudal oscillations of the cervical spinal cord are observed by phase-contrast MRI (PC-MRI) in healthy controls (HCs), while they become pathologically increased in patients suffering from degenerative cervical myelopathy. Whether transversal oscillations (i.e., anterior-posterior and right-left) also change in DCM patients is not known. Methods We assessed spinal cord motion simultaneously in all three spatial directions (i.e., cranio-caudal, anterior-posterior, and right-left) using sagittal PC-MRI and compared physiological oscillations in 18 HCs to pathological changes in 72 DCM patients with spinal canal stenosis. The parameter of interest was the amplitude of the velocity signal (i.e., maximum positive to maximum negative peak) during the cardiac cycle. Results Most patients suffered from mild DCM (mJOA score 16 (14-18) points), and the majority (68.1%) presented with multisegmental stenosis. The spinal canal was considerably constricted in DCM patients in all segments compared to HCs. Under physiological conditions in HCs, the cervical spinal cord oscillates in the cranio-caudal and anterior-posterior directions, while right-left motion was marginal [e.g., segment C5 amplitudes: cranio-caudal: 0.40 (0.27-0.48) cm/s; anterior-posterior: 0.18 (0.16-0.29) cm/s; right-left: 0.10 (0.08-0.13) cm/s]. Compared to HCs, DCM patients presented with considerably increased cranio-caudal oscillations due to the cardinal pathophysiologic change in non-stenotic [e.g., segment C5 amplitudes: 0.79 (0.49-1.32) cm/s] and stenotic segments [.g., segment C5 amplitudes: 0.99 (0.69-1.42) cm/s]). In contrast, right-left [e.g., segment C5 amplitudes: non-stenotic segment: 0.20 (0.13-0.32) cm/s; stenotic segment: 0.11 (0.09-0.18) cm/s] and anterior-posterior oscillations [e.g., segment C5 amplitudes: non-stenotic segment: 0.26 (0.15-0.45) cm/s; stenotic segment: 0.11 (0.09-0.18) cm/s] remained on low magnitudes comparable to HCs. Conclusion Increased cranio-caudal oscillations of the cervical cord are the cardinal pathophysiologic change and can be quantified using PC-MRI in DCM patients. This study addresses spinal cord oscillations as a relevant biomarker reflecting dynamic mechanical cord stress in DCM patients, potentially contributing to a loss of function.
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Affiliation(s)
- Nikolai Pfender
- Spinal Cord Injury Center, Balgrist University Hospital, Zurich, Switzerland
- University Spine Center Zurich, Balgrist University Hospital, Zurich, Switzerland
| | - Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, Zurich, Switzerland
- Department of Neurology, University Hospital Bern, Inselspital, Bern, Switzerland
| | - Carl M. Zipser
- Spinal Cord Injury Center, Balgrist University Hospital, Zurich, Switzerland
- University Spine Center Zurich, Balgrist University Hospital, Zurich, Switzerland
| | - Susanne Friedl
- Spinal Cord Injury Center, Balgrist University Hospital, Zurich, Switzerland
- University Spine Center Zurich, Balgrist University Hospital, Zurich, Switzerland
| | - Martin Schubert
- Spinal Cord Injury Center, Balgrist University Hospital, Zurich, Switzerland
- University Spine Center Zurich, Balgrist University Hospital, Zurich, Switzerland
| | - Reto Sutter
- Radiology, Balgrist University Hospital, Zurich, Switzerland
| | | | - José M. Spirig
- University Spine Center Zurich, Balgrist University Hospital, Zurich, Switzerland
| | - Michael Betz
- University Spine Center Zurich, Balgrist University Hospital, Zurich, Switzerland
| | - Patrick Freund
- Spinal Cord Injury Center, Balgrist University Hospital, Zurich, Switzerland
| | - Mazda Farshad
- University Spine Center Zurich, Balgrist University Hospital, Zurich, Switzerland
| | - Armin Curt
- Spinal Cord Injury Center, Balgrist University Hospital, Zurich, Switzerland
- University Spine Center Zurich, Balgrist University Hospital, Zurich, Switzerland
| | - Markus Hupp
- Spinal Cord Injury Center, Balgrist University Hospital, Zurich, Switzerland
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Streuli D, Nyirö L, Rosner J, Schilder A, Csato M, Schweinhardt P. Intra- and inter-session reliability of electrical detection and pain thresholds of cutaneous and muscle primary afferents in the lower back of healthy individuals. Pflugers Arch 2023; 475:1211-1223. [PMID: 37624386 PMCID: PMC10499933 DOI: 10.1007/s00424-023-02851-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 06/22/2023] [Accepted: 08/13/2023] [Indexed: 08/26/2023]
Abstract
To advance evidence-based practice and targeted treatments of low back pain (LBP), a better pathophysiological understanding and reliable outcome measures are required. The processing of nociceptive information from deeper somatic structures (e.g., muscle, fascia) might play an essential role in the pathophysiology of LBP. In this study, we measured the intra- and inter-session reliability of electrical detection and pain thresholds of cutaneous and muscle primary afferents of the lower back. Twenty healthy participants attended two study visits separated by 27.7 ± 1.7 days. To determine the location-specific electrical detection threshold (EDT) and pain threshold (EPT), needle electrodes were inserted in the epidermal layer over, and in the lumbar erector spinae muscle. Additionally, established quantitative sensory testing (QST) parameters were assessed. Reliability was determined by differences between measurements, intraclass correlation coefficients (ICC2,1), Bland-Altman plots, and standard error of measurement (SEM). Correspondence between QST parameters and electrical thresholds was assessed using Pearson's correlation. Except for cutaneous EPT, no significant (p ≤ 0.05) intra- and inter-session differences were observed. Excellent intra-session reliability was shown for cutaneous and intramuscular electrical stimulations and all QST parameters (ICC: 0.76-0.93). Inter-session reliabilities were good (ICC: 0.74-0.75) except for electrical stimulations (ICC: 0.08-0.36). Limits of agreement and SEM were higher for inter-session than intra-session. A medium to strong relationship was found between electrical and mechanical/pressure pain thresholds. In conclusion, cutaneous and intramuscular electrical stimulation will potentially close an important diagnostic gap regarding the selective examination of deep tissue afferents and provide location-specific information for the excitability of non-nociceptive and nociceptive afferents.
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Affiliation(s)
- Daniel Streuli
- Department of Chiropractic Medicine, Integrative Spinal Research, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Luana Nyirö
- Department of Chiropractic Medicine, Integrative Spinal Research, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.
| | - Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
- Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Andreas Schilder
- Department of Orthopaedics and Trauma Surgery, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Miklos Csato
- Department of Chiropractic Medicine, Integrative Spinal Research, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
- Department of Radiology, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Petra Schweinhardt
- Department of Chiropractic Medicine, Integrative Spinal Research, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
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9
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Widerström-Noga E, Biering-Sørensen F, Bryce TN, Cardenas DD, Finnerup NB, Jensen MP, Richards JS, Rosner J, Taylor J. The international spinal cord injury pain basic data set (version 3.0). Spinal Cord 2023; 61:536-540. [PMID: 37491608 DOI: 10.1038/s41393-023-00919-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 07/12/2023] [Accepted: 07/18/2023] [Indexed: 07/27/2023]
Abstract
STUDY DESIGN Expert opinion, feedback, revisions, and final consensus. OBJECTIVES To update the International Spinal Cord Injury Pain Basic Data Set (ISCIPBDS version 2.0) and incorporate suggestions from the SCI pain clinical and research community with respect to overall utility. SETTING International. METHODS The ISCIPBDS working group evaluated these suggestions and made modifications. The revised ISCIPBDS (Version 3.0) was then reviewed by members of the International SCI Data Sets Committee, the American Spinal Injury Association (ASIA) Board, the International Spinal Cord Society (ISCoS) Executive and Scientific Committees, individual reviewers and societies, and posted on the ASIA and ISCoS websites for 1 month to elicit comments before final approval by ASIA and ISCoS. RESULTS The ISCIPBDS (Version 3.0) was updated to make the dataset more flexible and useful: 1. The assessment can be based on the patient's perception of several of his/her "worst" pain(s) or based on the International SCI Pain (ISCIP) Classification-defined or other pain types, depending on the specific research questions or clinical needs. 2. Pain interference should usually be rated for overall pain but may also be used for specific pain problems if needed. 3. An optional pain drawing was added to complement the check box documentation of pain location. 4. Data categories consistent with the Extended Pain Dataset list of current treatments were added. 5. Several new training cases were added.
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Affiliation(s)
- Eva Widerström-Noga
- Miami Project to Cure Paralysis, University of Miami, Miller School of Medicine, Miami, FL, USA.
- Department of Physical Medicine and Rehabilitation, University of Miami, Miller School of Medicine, Miami, FL, USA.
| | - Fin Biering-Sørensen
- Department for Brain and Spinal Cord Injuries, Rigshospitalet, and Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Thomas N Bryce
- Department of Rehabilitation and Human Performance, The Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Diana D Cardenas
- Department of Physical Medicine and Rehabilitation, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Nanna B Finnerup
- Danish Pain Research Center, Department of Clinical medicine, Aarhus University, Aarhus, Denmark
| | - Mark P Jensen
- Department of Rehabilitation Medicine, University of Washington, Seattle, WA, USA
| | - J Scott Richards
- Department of Physical Medicine and Rehabilitation, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
- Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Julian Taylor
- Sensorimotor Function Group, Hospital Nacional de Parapléjicos, Servicio de Salud Castilla-La Mancha (SESCAM), Toledo, Spain
- Harris Manchester College, University of Oxford, Oxford, UK
- Instituto de Investigación Sanitaria de Castilla-La Mancha (SESCAM), Hospital Nacional de Parapléjicos, Toledo, Spain
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10
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Scheuren PS, Bösch S, Rosner J, Allmendinger F, Kramer JLK, Curt A, Hubli M. Priming of the autonomic nervous system after an experimental human pain model. J Neurophysiol 2023; 130:436-446. [PMID: 37405990 PMCID: PMC10625835 DOI: 10.1152/jn.00064.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 07/02/2023] [Accepted: 07/03/2023] [Indexed: 07/07/2023] Open
Abstract
Modulated autonomic responses to noxious stimulation have been reported in experimental and clinical pain. These effects are likely mediated by nociceptive sensitization, but may also, more simply reflect increased stimulus-associated arousal. To disentangle between sensitization- and arousal-mediated effects on autonomic responses to noxious input, we recorded sympathetic skin responses (SSRs) in response to 10 pinprick and heat stimuli before (PRE) and after (POST) an experimental heat pain model to induce secondary hyperalgesia (EXP) and a control model (CTRL) in 20 healthy females. Pinprick and heat stimuli were individually adapted for pain perception (4/10) across all assessments. Heart rate, heart rate variability, and skin conductance level (SCL) were assessed before, during, and after the experimental heat pain model. Both pinprick- and heat-induced SSRs habituated from PRE to POST in CTRL, but not EXP (P = 0.033). Background SCL (during stimuli application) was heightened in EXP compared with CTRL condition during pinprick and heat stimuli (P = 0.009). Our findings indicate that enhanced SSRs after an experimental pain model are neither fully related to subjective pain, as SSRs dissociated from perceptual responses, nor to nociceptive sensitization, as SSRs were enhanced for both modalities. Our findings can, however, be explained by priming of the autonomic nervous system during the experimental pain model, which makes the autonomic nervous system more susceptible to noxious input. Taken together, autonomic readouts have the potential to objectively assess not only nociceptive sensitization but also priming of the autonomic nervous system, which may be involved in the generation of distinct clinical pain phenotypes.NEW & NOTEWORTHY The facilitation of pain-induced sympathetic skin responses observed after experimentally induced central sensitization is unspecific to the stimulation modality and thereby unlikely solely driven by nociceptive sensitization. In addition, these enhanced pain-induced autonomic responses are also not related to higher stimulus-associated arousal, but rather a general priming of the autonomic nervous system. Hence, autonomic readouts may be able to detect generalized hyperexcitability in chronic pain, beyond the nociceptive system, which may contribute to clinical pain phenotypes.
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Affiliation(s)
- Paulina Simonne Scheuren
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
- Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Sofia Bösch
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
- Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
- Danish Pain Research Centre, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Florin Allmendinger
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - John Lawrence Kipling Kramer
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
- Department of Anesthesiology, Pharmacology & Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Armin Curt
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Michèle Hubli
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
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11
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De Schoenmacker I, Mollo A, Scheuren PS, Sirucek L, Brunner F, Schweinhardt P, Curt A, Rosner J, Hubli M. Central sensitization in CRPS patients with widespread pain: a cross-sectional study. Pain Med 2023; 24:974-984. [PMID: 36946277 PMCID: PMC10391588 DOI: 10.1093/pm/pnad040] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 03/08/2023] [Accepted: 03/20/2023] [Indexed: 03/23/2023]
Abstract
OBJECTIVE Widespread pain hypersensitivity and enhanced temporal summation of pain (TSP) are commonly reported in patients with complex regional pain syndrome (CRPS) and discussed as proxies for central sensitization. This study aimed to directly relate such signs of neuronal hyperexcitability to the pain phenotype of CRPS patients. METHODS Twenty-one CRPS patients and 20 healthy controls (HC) were recruited. The pain phenotype including spatial pain extent (assessed in % body surface) and intensity were assessed and related to widespread pain hypersensitivity, TSP, and psychological factors. Quantitative sensory testing (QST) was performed in the affected, the contralateral and a remote (control) area. RESULTS CRPS patients showed decreased pressure pain thresholds in all tested areas (affected: t(34) = 4.98, P < .001, contralateral: t(35) = 3.19, P = .005, control: t(31) = 2.65, P = .012). Additionally, patients showed increased TSP in the affected area (F(3,111) = 4.57, P = .009) compared to HC. TSP was even more enhanced in patients with a high compared to a low spatial pain extent (F(3,51) = 5.67, P = .008), suggesting pronounced spinal sensitization in patients with extended pain patterns. Furthermore, the spatial pain extent positively correlated with the Bath Body Perception Disturbance Scale (ρ = 0.491; P = .048). CONCLUSIONS Overall, we provide evidence that the pain phenotype in CRPS, that is, spatial pain extent, might be related to sensitization mechanism within the central nociceptive system. This study points towards central neuronal excitability as a potential therapeutic target in patients with more widespread CRPS.
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Affiliation(s)
- Iara De Schoenmacker
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, 8008 Zurich, Switzerland
| | - Anna Mollo
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, 8008 Zurich, Switzerland
| | - Paulina Simonne Scheuren
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, 8008 Zurich, Switzerland
| | - Laura Sirucek
- Integrative Spinal Research, Department of Chiropractic Medicine, University Hospital Balgrist, University of Zurich, 8008 Zurich, Switzerland
| | - Florian Brunner
- Physical Medicine and Rheumatology, Balgrist University Hospital, 8008 Zurich, Switzerland
| | - Petra Schweinhardt
- Integrative Spinal Research, Department of Chiropractic Medicine, University Hospital Balgrist, University of Zurich, 8008 Zurich, Switzerland
- Alan Edward Center for Research on Pain, McGill University, Montreal, Quebec, Canada
| | - Armin Curt
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, 8008 Zurich, Switzerland
| | - Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, 8008 Zurich, Switzerland
- Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
- Danish Pain Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Michèle Hubli
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, 8008 Zurich, Switzerland
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Huynh V, Lütolf R, Rosner J, Luechinger R, Curt A, Kollias S, Michels L, Hubli M. Intrinsic brain connectivity alterations despite intact pain inhibition in subjects with neuropathic pain after spinal cord injury: a pilot study. Sci Rep 2023; 13:11943. [PMID: 37488130 PMCID: PMC10366123 DOI: 10.1038/s41598-023-37783-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Accepted: 06/27/2023] [Indexed: 07/26/2023] Open
Abstract
Endogenous pain modulation in humans is frequently investigated with conditioned pain modulation (CPM). Deficient pain inhibition is a proposed mechanism that contributes to neuropathic pain (NP) after spinal cord injury (SCI). Recent studies have combined CPM testing and neuroimaging to reveal neural correlates of CPM efficiency in chronic pain. This study investigated differences in CPM efficiency in relation to resting-state functional connectivity (rsFC) between 12 SCI-NP subjects and 13 age- and sex-matched healthy controls (HC). Twelve and 11 SCI-NP subjects were included in psychophysical and rsFC analyses, respectively. All HC were included in the final analyses. Psychophysical readouts were analysed to determine CPM efficiency within and between cohorts. Group differences of rsFC, in relation to CPM efficiency, were explored with seed-to-voxel rsFC analyses with pain modulatory regions, e.g. ventrolateral periaqueductal gray (vlPAG) and amygdala. Overall, pain inhibition was not deficient in SCI-NP subjects and was greater in those with more intense NP. Greater pain inhibition was associated with weaker rsFC between the vlPAG and amygdala with the visual and frontal cortex, respectively, in SCI-NP subjects but with stronger rsFC in HC. Taken together, SCI-NP subjects present with intact pain inhibition, but can be differentiated from HC by an inverse relationship between CPM efficiency and intrinsic connectivity of supraspinal regions. Future studies with larger cohorts are necessary to consolidate the findings in this study.
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Affiliation(s)
- Vincent Huynh
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Forchstrasse 340, 8008, Zurich, Switzerland.
- Department of Neuroradiology, Clinical Neuroscience Center, University Hospital Zurich & University of Zurich, Zurich, Switzerland.
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Forchstrasse 340, 8008, Zurich, Switzerland.
| | - Robin Lütolf
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Forchstrasse 340, 8008, Zurich, Switzerland
| | - Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Forchstrasse 340, 8008, Zurich, Switzerland
- Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Roger Luechinger
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Armin Curt
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Forchstrasse 340, 8008, Zurich, Switzerland
| | - Spyridon Kollias
- Department of Neuroradiology, Clinical Neuroscience Center, University Hospital Zurich & University of Zurich, Zurich, Switzerland
| | - Lars Michels
- Department of Neuroradiology, Clinical Neuroscience Center, University Hospital Zurich & University of Zurich, Zurich, Switzerland
| | - Michèle Hubli
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Forchstrasse 340, 8008, Zurich, Switzerland
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13
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Nowacki A, Zhang D, Wermelinger J, Abel Alvarez Abut P, Rosner J, Pollo C, Seidel K. Directional recordings of somatosensory evoked potentials from the sensory thalamus in chronic poststroke pain patients. Clin Neurophysiol 2023; 151:50-58. [PMID: 37156120 DOI: 10.1016/j.clinph.2023.03.359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 03/27/2023] [Accepted: 03/29/2023] [Indexed: 05/10/2023]
Abstract
OBJECTIVE The aim of this feasibility study was to investigate the properties of median nerve somatosensory evoked potential (SEPs) recorded from segmented Deep Brain Stimulation (DBS) leads in the sensory thalamus (VP) and how they relate to clinical and anatomical findings. METHODS We analyzed four patients with central post-stroke pain and DBS electrodes placed in the VP. Median nerve SEPs were recorded with referential and bipolar montages. Electrode positions were correlated with thalamus anatomy and tractography-based medial lemniscus. Early postoperative clinical paresthesia mapping was performed by an independent pain nurse. Finally, we performed frequency and time-frequency analyses of the signals. RESULTS We observed differences of SEP amplitudes recorded along different directions in the VP. SEP amplitudes did not clearly correlate to both atlas-based anatomical position and fiber-tracking results of the medial lemniscus. However, the contacts of highest SEP amplitude correlated with the contacts of lowest effect-threshold to induce paraesthesia. CONCLUSIONS SEP recordings from directional DBS leads offer additional information about the neurophysiological (re)organization of the sensory thalamus. SIGNIFICANCE Directional recordings of thalamic SEPs bear the potential to assist clinical decision-making in DBS for pain.
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Affiliation(s)
- Andreas Nowacki
- Department of Neurosurgery, Inselspital, Bern University Hospital, University Bern, Bern, Switzerland.
| | - David Zhang
- Department of Neurosurgery, Inselspital, Bern University Hospital, University Bern, Bern, Switzerland
| | - Jonathan Wermelinger
- Department of Neurosurgery, Inselspital, Bern University Hospital, University Bern, Bern, Switzerland
| | - Pablo Abel Alvarez Abut
- Department of Neurosurgery, Inselspital, Bern University Hospital, University Bern, Bern, Switzerland
| | - Jan Rosner
- Department of Neurology, Inselspital, Bern University Hospital, University Bern, Bern, Switzerland; Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Claudio Pollo
- Department of Neurosurgery, Inselspital, Bern University Hospital, University Bern, Bern, Switzerland
| | - Kathleen Seidel
- Department of Neurosurgery, Inselspital, Bern University Hospital, University Bern, Bern, Switzerland
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14
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Scheuren PS, De Schoenmacker I, Rosner J, Brunner F, Curt A, Hubli M. Pain-autonomic measures reveal nociceptive sensitization in complex regional pain syndrome. Eur J Pain 2023; 27:72-85. [PMID: 36130736 PMCID: PMC10092513 DOI: 10.1002/ejp.2040] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 09/01/2022] [Accepted: 09/17/2022] [Indexed: 12/15/2022]
Abstract
BACKGROUND Allodynia and hyperalgesia are common signs in individuals with complex regional pain syndrome (CRPS), mainly attributed to sensitization of the nociceptive system. Appropriate diagnostic tools for the objective assessment of such hypersensitivities are still lacking, which are essential for the development of mechanism-based treatment strategies. OBJECTIVES This study investigated the use of pain-autonomic readouts to objectively detect sensitization processes in CRPS. METHODS Twenty individuals with chronic CRPS were recruited for the study alongside 16 age- and sex-matched healthy controls (HC). All individuals underwent quantitative sensory testing and neurophysiological assessments. Sympathetic skin responses (SSRs) were recorded in response to 15 pinprick and 15 noxious heat stimuli of the affected (CRPS hand/foot) and a control area (contralateral shoulder/hand). RESULTS Individuals with CRPS showed increased mechanical pain sensitivity and increased SSR amplitudes compared with HC in response to pinprick and heat stimulation of the affected (p < 0.001), but not in the control area (p > 0.05). Habituation of pinprick-induced SSRs was reduced in CRPS compared to HC in both the affected (p = 0.018) and slightly in the control area (p = 0.048). Habituation of heat-induced SSR was reduced in CRPS in the affected (p = 0.008), but not the control area (p = 0.053). CONCLUSIONS This is the first study demonstrating clinical evidence that pain-related autonomic responses may represent objective tools to quantify sensitization processes along the nociceptive neuraxis in CRPS (e.g. widespread hyperexcitability). Pain-autonomic readouts could help scrutinize mechanisms underlying the development and maintenance of chronic pain in CRPS and provide valuable metrics to detect mechanism-based treatment responses in clinical trials. SIGNIFICANCE This study provides clinical evidence that autonomic measures to noxious stimuli can objectively detect sensitization processes along the nociceptive neuraxis in complex regional pain syndrome (CRPS) (e.g. widespread hyperexcitability). Pain-autonomic readouts may represent valuable tools to explore pathophysiological mechanisms in a variety of pain patients and offer novel avenues to help guide mechanism-based therapeutic strategies.
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Affiliation(s)
- Paulina S Scheuren
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.,Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Iara De Schoenmacker
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.,Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Florian Brunner
- Department of Physical Medicine and Rheumatology, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Armin Curt
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Michèle Hubli
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
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15
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Lütolf R, Rosner J, Curt A, Hubli M. Indicators of central sensitization in chronic neuropathic pain after spinal cord injury. Eur J Pain 2022; 26:2162-2175. [PMID: 36008094 PMCID: PMC9826442 DOI: 10.1002/ejp.2028] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 08/01/2022] [Accepted: 08/20/2022] [Indexed: 01/11/2023]
Abstract
BACKGROUND Central sensitization is considered a key mechanism underlying neuropathic pain (NP) after spinal cord injury (SCI). METHODS Two novel proxies for central sensitization were investigated in thoracic SCI subjects with (SCI-NP) and without NP (SCI-nonNP) compared to healthy controls (HC). Specifically, temporal summation of pain (TSP) was investigated by examining pain ratings during a 2-min tonic heat application to the volar forearm. Additionally, palmar heat-induced sympathetic skin responses (SSR) were recorded in order to reveal changes in pain-autonomic interaction above the lesion level. Pain extent was assessed as the percentage of the body area and the number of body regions being affected by NP. RESULTS Enhanced TSP was observed in SCI-NP (+66%) compared to SCI-nonNP (-75%, p = 0.009) and HC (-59%, p = 0.021). In contrast, no group differences were found (p = 0.685) for SSR habituation. However, pain extent in SCI-NP was positively correlated with deficient SSR habituation (body area: r = 0.561, p = 0.024; body regions: r = 0.564, p = 0.023). CONCLUSIONS These results support the value of TSP and heat-induced SSRs as proxies for central sensitization in widespread neuropathic pain syndromes after SCI. Measures of pain-autonomic interaction emerged as a promising tool for the objective investigation of sensitized neuronal states in chronic pain conditions. SIGNIFICANCE We present two surrogate readouts for central sensitization in neuropathic pain following SCI. On the one hand, temporal summation of tonic heat pain is enhanced in subjects with neuropathic pain. On the other hand, pain-autonomic interaction reveals potential advanced measures in chronic pain, as subjects with a high extent of neuropathic pain showed diminished habituation of pain-induced sympathetic measures. A possible implication for clinical practice is constituted by an improved assessment of neuronal hyperexcitability potentially enabling mechanism-based treatment.
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Affiliation(s)
- Robin Lütolf
- Spinal Cord Injury CenterBalgrist University Hospital, University of ZurichZurichSwitzerland
| | - Jan Rosner
- Spinal Cord Injury CenterBalgrist University Hospital, University of ZurichZurichSwitzerland,Department of NeurologyUniversity Hospital Bern, Inselspital, University of BernBernSwitzerland
| | - Armin Curt
- Spinal Cord Injury CenterBalgrist University Hospital, University of ZurichZurichSwitzerland
| | - Michèle Hubli
- Spinal Cord Injury CenterBalgrist University Hospital, University of ZurichZurichSwitzerland
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16
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Lütolf R, De Schoenmacker I, Rosner J, Sirucek L, Schweinhardt P, Curt A, Hubli M. Anti- and Pro-Nociceptive mechanisms in neuropathic pain after human spinal cord injury. Eur J Pain 2022; 26:2176-2187. [PMID: 36000307 PMCID: PMC9826499 DOI: 10.1002/ejp.2029] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 08/01/2022] [Accepted: 08/20/2022] [Indexed: 01/11/2023]
Abstract
BACKGROUND Deficient endogenous pain modulation and increased nociceptive excitability are key features of central sensitization and can be assessed in humans by conditioned pain modulation (CPM, anti-nociceptive) and temporal summation of pain (TSP, pro-nociceptive), respectively. This study aimed to investigate these measures as proxies for central sensitization in subjects with chronic neuropathic pain (NP) after spinal cord injury (SCI). METHODS In paraplegic subjects with NP (SCI-NP; n = 17) and healthy controls (HC; n = 17), parallel and sequential sham-controlled CPM paradigms were performed using pressure pain threshold at the hand, that is, above lesion level, as test stimulus. The conditioning stimulus was a noxious cold (verum) or lukewarm water bath (sham) applied contralaterally. Regarding pro-nociceptive mechanisms, a TSP protocol with individually-adjusted pressure pain stimuli at the thenar eminence was used. CPM and TSP magnitudes were related to intensity and spatial extent of spontaneous NP. RESULTS Neither the parallel nor sequential sham-controlled CPM paradigm showed any significant inhibition of above-level pressure pain thresholds for SCI-NP or HC. Accordingly, no group difference in CPM capacity was found, however, subjects with more intense spontaneous NP showed lower inhibitory CPM capacity. TSP was observed for both groups but was not enhanced in SCI-NP. CONCLUSIONS Our results do not support altered above-level anti- or pro-nociceptive mechanisms in SCI-NP compared with HC; however, they also highlight the relevance of spontaneous NP intensity with regards to the capacity of endogenous pain modulation in SCI subjects. SIGNIFICANCE Central sensitization encompasses deficient endogenous pain modulation and increased nociceptive excitability. These two mechanisms can be assessed in humans by conditioned pain modulation and temporal summation of pain, respectively. Our data demonstrates a lack of descending pain inhibition only in subjects with severe neuropathic pain which may hint towards central sensitization at spinal and/or supra-spinal levels. Disentangling the mechanisms of endogenous pain modulation and neuronal hyperexcitability might improve mechanism-based treatment of neuropathic pain in subjects with spinal cord injury.
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Affiliation(s)
- Robin Lütolf
- Spinal Cord Injury Center, Balgrist University HospitalUniversity of ZurichZurichSwitzerland
| | - Iara De Schoenmacker
- Spinal Cord Injury Center, Balgrist University HospitalUniversity of ZurichZurichSwitzerland
| | - Jan Rosner
- Spinal Cord Injury Center, Balgrist University HospitalUniversity of ZurichZurichSwitzerland,Department of NeurologyUniversity Hospital Bern, Inselspital, University of BernBernSwitzerland
| | - Laura Sirucek
- Integrative Spinal Research, Department of Chiropractic MedicineBalgrist University Hospital, University of ZurichZurichSwitzerland
| | - Petra Schweinhardt
- Integrative Spinal Research, Department of Chiropractic MedicineBalgrist University Hospital, University of ZurichZurichSwitzerland
| | - Armin Curt
- Spinal Cord Injury Center, Balgrist University HospitalUniversity of ZurichZurichSwitzerland
| | - Michèle Hubli
- Spinal Cord Injury Center, Balgrist University HospitalUniversity of ZurichZurichSwitzerland
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17
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Archibald J, Ortiz O, Enzler A, Rosner J, Kramer JLK. Supraspinal facilitation to repetitive painful stimulation: A laser evoked potential study. J Neurophysiol 2022; 128:1143-1151. [PMID: 36130178 DOI: 10.1152/jn.00283.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
To better characterize central modulation mechanisms involved in the processing of daily repetitive painful stimulation, laser evoked potentials were recorded at and away from the conditioning area in healthy participants. In addition, we aimed to evaluate a repetitive painful stimulation paradigm that could be conducted in a shorter time frame than previous studies. Collectively, continuous pain rating, warm and heat pain threshold results suggest that sensitivity to pain was reduced 24 hours after the shortened repeated painful stimulation. Laser evoked potentials revealed a significant increase in the contralateral arm to where the conditioning stimulus was applied. This finding was specific to noxious conditioning (i.e., not seen in the control brush experiment). These results provide neurophysiological evidence of pain facilitation resulting from prolonged exposure to painful heat, potentially arising in supraspinal structures.
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Affiliation(s)
- Jessica Archibald
- nternational Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, BC, Canada.,Department of Experimental Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Oscar Ortiz
- nternational Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, BC, Canada
| | - Alinda Enzler
- Department of Health Science and Technologies, Federal Institute of Technology Zurich, Switzerland
| | - Jan Rosner
- nternational Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, BC, Canada.,Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.,Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - John L K Kramer
- nternational Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, BC, Canada.,Department of Experimental Medicine, University of British Columbia, Vancouver, BC, Canada.,Department ofAnesthesiology, Pharmacology,and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
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Heldner MR, Chalfine C, Houot M, Umarova RM, Rosner J, Lippert J, Gallucci L, Leger A, Baronnet F, Samson Y, Rosso C. Cognitive Status Predicts Return to Functional Independence After Minor Stroke: A Decision Tree Analysis. Front Neurol 2022; 13:833020. [PMID: 35250835 PMCID: PMC8891604 DOI: 10.3389/fneur.2022.833020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 01/10/2022] [Indexed: 11/13/2022] Open
Abstract
About two-thirds of patients with minor strokes are discharged home. However, these patients may have difficulties returning to their usual living activities. To investigate the factors associated with successful home discharge, our aim was to provide a decision tree (based on clinical data) that could identify if a patient discharged home could return to pre-stroke activities and to perform an external validation of this decision tree on an independent cohort. Two cohorts of patients with minor strokes gathered from stroke registries at the Hôpital Pitié-Salpêtrière and University Hospital Bern were included in this study (n = 105 for the construction cohort coming from France; n = 100 for the second cohort coming from Switzerland). The decision tree was built using the classification and regression tree (CART) analysis on the construction cohort. It was then applied to the validation cohort. Accuracy, sensitivity, specificity, false positive, and false-negative rates were reported for both cohorts. In the construction cohort, 60 patients (57%) returned to their usual, pre-stroke level of independence. The CART analysis produced a decision tree with the Montreal Cognitive Assessment (MoCA) as the first decision point, followed by discharge NIHSS score or age, and then by the occupational status. The overall prediction accuracy to the favorable outcome was 80% in the construction cohort and reached 72% accuracy in the validation cohort. This decision tree highlighted the role of cognitive function as a crucial factor for patients to return to their usual activities after a minor stroke. The algorithm may help clinicians to tailor planning of patients' discharge.
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Affiliation(s)
- Mirjam R. Heldner
- Department of Neurology, Inselspital, University Hospital and University of Bern, Bern, Switzerland
| | - Caroline Chalfine
- Assistance Publique – Hôpitaux de Paris (APHP) Service de Soins de Suite et Réadaptation, Hôpital Pitié-Salpêtrière, Paris, France
| | - Marion Houot
- Assistance Publique – Hôpitaux de Paris (APHP) Centre d'Investigations Cliniques de Neurosciences, Hôpital Pitié-Salpêtrière, Paris, France
- Inserm U 1127, CNRS UMR 7225, Sorbonne Université, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière (ICM), Paris, France
| | - Roza M. Umarova
- Department of Neurology, Inselspital, University Hospital and University of Bern, Bern, Switzerland
| | - Jan Rosner
- Department of Neurology, Inselspital, University Hospital and University of Bern, Bern, Switzerland
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Julian Lippert
- Department of Neurology, Inselspital, University Hospital and University of Bern, Bern, Switzerland
| | - Laura Gallucci
- Department of Neurology, Inselspital, University Hospital and University of Bern, Bern, Switzerland
| | - Anne Leger
- STARE Team, iCRIN, Institut du Cerveau et de la Moelle épinière (ICM), Paris, France
- APHP-Urgences Cérébro-Vasculaires, Hôpital Pitié-Salpêtrière, Paris, France
| | - Flore Baronnet
- STARE Team, iCRIN, Institut du Cerveau et de la Moelle épinière (ICM), Paris, France
- APHP-Urgences Cérébro-Vasculaires, Hôpital Pitié-Salpêtrière, Paris, France
| | - Yves Samson
- STARE Team, iCRIN, Institut du Cerveau et de la Moelle épinière (ICM), Paris, France
- APHP-Urgences Cérébro-Vasculaires, Hôpital Pitié-Salpêtrière, Paris, France
| | - Charlotte Rosso
- Inserm U 1127, CNRS UMR 7225, Sorbonne Université, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière (ICM), Paris, France
- STARE Team, iCRIN, Institut du Cerveau et de la Moelle épinière (ICM), Paris, France
- APHP-Urgences Cérébro-Vasculaires, Hôpital Pitié-Salpêtrière, Paris, France
- *Correspondence: Charlotte Rosso
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19
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Pfender N, Rosner J, Zipser CM, Friedl S, Vallotton K, Sutter R, Klarhoefer M, Schubert M, Betz M, Spirig JM, Seif M, Hubli M, Freund P, Farshad M, Curt A, Hupp M. Comparison of axial and sagittal spinal cord motion measurements in degenerative cervical myelopathy. J Neuroimaging 2022; 32:1121-1133. [PMID: 35962464 PMCID: PMC9805009 DOI: 10.1111/jon.13035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 07/27/2022] [Accepted: 07/27/2022] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND AND PURPOSE The timing of decision-making for a surgical intervention in patients with mild degenerative cervical myelopathy (DCM) is challenging. Spinal cord motion phase contrast MRI (PC-MRI) measurements can reveal the extent of dynamic mechanical strain on the spinal cord to potentially identify high-risk patients. This study aims to determine the comparability of axial and sagittal PC-MRI measurements of spinal cord motion with the prospect of improving the clinical workup. METHODS Sixty-four DCM patients underwent a PC-MRI scan assessing spinal cord motion. The agreement of axial and sagittal measurements was determined by means of intraclass correlation coefficients (ICCs) and Bland-Altman analyses. RESULTS The comparability of axial and sagittal PC-MRI measurements was good to excellent at all cervical levels (ICCs motion amplitude: .810-.940; p < .001). Significant differences between axial and sagittal amplitude values could be found at segments C3 and C4, while its magnitude was low (C3: 0.07 ± 0.19 cm/second; C4: -0.12 ± 0.30 cm/second). Bland-Altman analysis showed a good agreement between axial and sagittal PC-MRI scans (coefficients of repeatability: minimum -0.23 cm/second at C2; maximum -0.58 cm/second at C4). Subgroup analysis regarding anatomic conditions (stenotic vs. nonstenotic segments) and different velocity encoding (2 vs. 3 cm/second) showed comparable results. CONCLUSIONS This study demonstrates good comparability between axial and sagittal spinal cord motion measurements in DCM patients. To this end, axial and sagittal PC-MRI are both accurate and sensitive in detecting pathologic cord motion. Therefore, such measures could identify high-risk patients and improve clinical decision-making (ie, timing of decompression).
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Affiliation(s)
- Nikolai Pfender
- Spinal Cord Injury CenterBalgrist University HospitalUniversity of ZurichZurichSwitzerland
| | - Jan Rosner
- Spinal Cord Injury CenterBalgrist University HospitalUniversity of ZurichZurichSwitzerland,Department of NeurologyBern University HospitalInselspitalUniversity of BernBernSwitzerland
| | - Carl Moritz Zipser
- Spinal Cord Injury CenterBalgrist University HospitalUniversity of ZurichZurichSwitzerland
| | - Susanne Friedl
- Spinal Cord Injury CenterBalgrist University HospitalUniversity of ZurichZurichSwitzerland
| | - Kevin Vallotton
- Spinal Cord Injury CenterBalgrist University HospitalUniversity of ZurichZurichSwitzerland
| | - Reto Sutter
- RadiologyBalgrist University HospitalUniversity of ZurichZurichSwitzerland
| | | | - Martin Schubert
- Spinal Cord Injury CenterBalgrist University HospitalUniversity of ZurichZurichSwitzerland
| | - Michael Betz
- University Spine Centre ZurichBalgrist University HospitalUniversity of ZurichZurichSwitzerland
| | - José Miguel Spirig
- University Spine Centre ZurichBalgrist University HospitalUniversity of ZurichZurichSwitzerland
| | - Maryam Seif
- Spinal Cord Injury CenterBalgrist University HospitalUniversity of ZurichZurichSwitzerland,Department of NeurophysicsMax Planck Institute for Human Cognitive and Brain SciencesLeipzigGermany
| | - Michèle Hubli
- Spinal Cord Injury CenterBalgrist University HospitalUniversity of ZurichZurichSwitzerland
| | - Patrick Freund
- Spinal Cord Injury CenterBalgrist University HospitalUniversity of ZurichZurichSwitzerland
| | - Mazda Farshad
- University Spine Centre ZurichBalgrist University HospitalUniversity of ZurichZurichSwitzerland
| | - Armin Curt
- Spinal Cord Injury CenterBalgrist University HospitalUniversity of ZurichZurichSwitzerland,University Spine Centre ZurichBalgrist University HospitalUniversity of ZurichZurichSwitzerland
| | - Markus Hupp
- Spinal Cord Injury CenterBalgrist University HospitalUniversity of ZurichZurichSwitzerland
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20
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Huynh V, Lütolf R, Rosner J, Luechinger R, Curt A, Kollias S, Michels L, Hubli M. Descending pain modulatory efficiency in healthy subjects is related to structure and resting connectivity of brain regions. Neuroimage 2021; 247:118742. [PMID: 34863962 DOI: 10.1016/j.neuroimage.2021.118742] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 10/26/2021] [Accepted: 11/16/2021] [Indexed: 12/21/2022] Open
Abstract
The descending pain modulatory system in humans is commonly investigated using conditioned pain modulation (CPM). Whilst variability in CPM efficiency, i.e., inhibition and facilitation, is normal in healthy subjects, exploring the inter-relationship between brain structure, resting-state functional connectivity (rsFC) and CPM readouts will provide greater insight into the underlying CPM efficiency seen in healthy individuals. Thus, this study combined CPM testing, voxel-based morphometry (VBM) and rsFC to identify the neural correlates of CPM in a cohort of healthy subjects (n =40), displaying pain inhibition (n = 29), facilitation (n = 10) and no CPM effect (n = 1). Clusters identified in the VBM analysis were implemented in the rsFC analysis alongside key constituents of the endogenous pain modulatory system. Greater pain inhibition was related to higher volume of left frontal cortices and stronger rsFC between the motor cortex and periaqueductal grey. Conversely, weaker pain inhibition was related to higher volume of the right frontal cortex - coupled with stronger rsFC to the primary somatosensory cortex, and rsFC between the amygdala and posterior insula. Overall, healthy subjects showed higher volume and stronger rsFC of brain regions involved with descending modulation, while the lateral and medial pain systems were related to greater pain inhibition and facilitation during CPM, respectively. These findings reveal structural alignments and functional interactions between supraspinal areas involved in CPM efficiency. Ultimately understanding these underlying variations and how they may become affected in chronic pain conditions, will advance a more targeted subgrouping in pain patients for future cross-sectional studies investigating endogenous pain modulation.
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Affiliation(s)
- Vincent Huynh
- Department of Neuroradiology, Clinical Neuroscience Center, University Hospital Zurich & University of Zurich, Zurich, Switzerland; Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Forchstrasse 340, Zurich 8008, Switzerland.
| | - Robin Lütolf
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Forchstrasse 340, Zurich 8008, Switzerland
| | - Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Forchstrasse 340, Zurich 8008, Switzerland; Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Roger Luechinger
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Armin Curt
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Forchstrasse 340, Zurich 8008, Switzerland
| | - Spyros Kollias
- Department of Neuroradiology, Clinical Neuroscience Center, University Hospital Zurich & University of Zurich, Zurich, Switzerland
| | - Lars Michels
- Department of Neuroradiology, Clinical Neuroscience Center, University Hospital Zurich & University of Zurich, Zurich, Switzerland
| | - Michèle Hubli
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Forchstrasse 340, Zurich 8008, Switzerland
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21
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Lütolf R, Rosner J, Curt A, Hubli M. Identifying Discomplete Spinal Lesions: New Evidence from Pain-Autonomic Interaction in Spinal Cord Injury. J Neurotrauma 2021; 38:3456-3466. [PMID: 34806429 DOI: 10.1089/neu.2021.0280] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The clinical evaluation of spinal afferents is an important diagnostic and prognostic marker for neurological and functional recovery after spinal cord injury (SCI). Particularly important regarding neuropathic pain following SCI is the function of the spinothalamic tract (STT) conveying nociceptive and temperature information. Here, we investigated the added value of neurophysiological methods revealing discomplete STT lesions; that is, residual axonal sparing in clinically complete STT lesions. Specifically, clinical pinprick testing and thermal thresholds were compared with objective contact heat-evoked potentials (CHEPs) and a novel measure of pain-autonomic interaction employing heat-induced sympathetic skin responses (SSR). The test stimuli (i.e., contact heat, pinprick) were applied below the lesion level in 32 subjects with thoracic SCI while corresponding heat-evoked responses (i.e., CHEPs and SSR) were recorded above the lesion (i.e., scalp and hand, respectively). Readouts of STT function were related to neuropathic pain characteristics. In subjects with abolished pinprick sensation, measures of thermosensation (10%), CHEPs (33%), and SSR (48%) revealed residual STT function. Importantly, SSRs can be used as an objective readout and when abolished, no other proxy indicated residual STT function. No relationship was found between STT function readouts and spontaneous neuropathic pain intensity and extent. However, subjects with clinically preserved STT function presented more often with allodynia (54%) than subjects with discomplete (13%) or complete STT lesions (18%). In individuals with absent pinprick sensation, discomplete STT lesions can be revealed employing pain-autonomic measures. The improved sensitivity to discerning STT lesion completeness might support the investigation of its association with neuropathic pain following SCI.
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Affiliation(s)
- Robin Lütolf
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.,Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Armin Curt
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Michèle Hubli
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
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22
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Kuramoto LK, Sobolev BG, Rosner J, Brasher PMA, Azoulay L, Cragg JJ. A systematic, concept-based method of developing the exposure measure for drug safety and effectiveness studies. Pharmacoepidemiol Drug Saf 2021; 31:13-21. [PMID: 34657356 DOI: 10.1002/pds.5372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 10/12/2021] [Indexed: 11/05/2022]
Abstract
PURPOSE In drug safety and effectiveness studies based on secondary data, the choice of an appropriate exposure measure for a given outcome can be challenging. Different measures of exposure can yield different estimates of treatment effect and safety. There is a knowledge gap with respect to developing and refining measures of drug exposure, to ensure that the exposure measure addresses the study question and is suitable for statistical analysis. METHODS We present a transparent, step-by-step approach to the development of drug exposure measures involving secondary data. This approach would be of interest to students and investigators with initial training in pharmacoepidemiology. We illustrate the approach using a study about Parkinson's disease. RESULTS We described the exposure specifications according to the study question. Next, we refined the exposure measure by linking it to knowledge about four major concepts in drug safety and effectiveness studies: drug use patterns, duration, timing, and dose. We then used this knowledge to guide the ultimate choice of exposure measure: time-varying, cumulative 6-month exposure to tamsulosin (a drug used to treat prostate hyperplasia). CONCLUSIONS The proposed approach links exposure specifications to four major concepts in drug safety and effectiveness studies. Formulating subject-matter knowledge about these major concepts provides an avenue to develop the rationale and specifications for the exposure measure.
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Affiliation(s)
- Lisa K Kuramoto
- Centre for Clinical Epidemiology & Evaluation, Vancouver Coastal Health Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Boris G Sobolev
- Centre for Clinical Epidemiology & Evaluation, Vancouver Coastal Health Research Institute, University of British Columbia, Vancouver, British Columbia, Canada.,School of Population and Public Health, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jan Rosner
- Collaboration for Outcomes Research and Evaluation (CORE), Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Penelope M A Brasher
- Centre for Clinical Epidemiology & Evaluation, Vancouver Coastal Health Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Laurent Azoulay
- Department of Epidemiology, Biostatistics, and Occupational Health, and Gerald Bronfman Department of Oncology, McGill University, Montreal, Quebec, Canada
| | - Jacquelyn J Cragg
- Collaboration for Outcomes Research and Evaluation (CORE), Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada.,International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
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23
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Scheuren PS, David G, Kramer JLK, Jutzeler CR, Hupp M, Freund P, Curt A, Hubli M, Rosner J. Combined Neurophysiologic and Neuroimaging Approach to Reveal the Structure-Function Paradox in Cervical Myelopathy. Neurology 2021; 97:e1512-e1522. [PMID: 34380751 DOI: 10.1212/wnl.0000000000012643] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 07/16/2021] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND AND OBJECTIVES To explore the so-called structure-function paradox in individuals with focal spinal lesions by means of tract-specific MRI coupled with multimodal evoked potentials and quantitative sensory testing. METHODS Individuals with signs and symptoms attributable to cervical myelopathy (i.e., no evidence of competing neurologic diagnoses) were recruited at the Balgrist University Hospital, Zurich, Switzerland, between February 2018 and March 2019. We evaluated the relationship between the extent of structural damage within spinal nociceptive pathways (i.e., dorsal horn, spinothalamic tract, anterior commissure) assessed with atlas-based MRI and (1) the functional integrity of spinal nociceptive pathways measured with contact heat-, cold-, and pinprick-evoked potentials and (2) clinical somatosensory phenotypes assessed with quantitative sensory testing. RESULTS Sixteen individuals (mean age 61 years) with either degenerative (n = 13) or posttraumatic (n = 3) cervical myelopathy participated in the study. Most individuals presented with mild myelopathy (modified Japanese Orthopaedic Association score >15; n = 13). A total of 71% of individuals presented with structural damage within spinal nociceptive pathways on MRI. However, 50% of these individuals presented with complete functional sparing (i.e., normal contact heat-, cold-, and pinprick-evoked potentials). The extent of structural damage within spinal nociceptive pathways was not associated with functional integrity of thermal (heat: p = 0.57; cold: p = 0.49) and mechano-nociceptive pathways (p = 0.83) or with the clinical somatosensory phenotype (heat: p = 0.16; cold: p = 0.37; mechanical: p = 0.73). The amount of structural damage to the spinothalamic tract did not correlate with spinothalamic conduction velocity (p > 0.05; ρ = -0.11). DISCUSSION Our findings provide neurophysiologic evidence to substantiate that structural damage in the spinal cord does not equate to functional somatosensory deficits. This study recognizes the pronounced structure-function paradox in cervical myelopathies and underlines the inevitable need for a multimodal phenotyping approach to reveal the eloquence of lesions within somatosensory pathways.
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Affiliation(s)
- Paulina Simonne Scheuren
- From the Spinal Cord Injury Center (P.S.S., G.D., M. Hupp, P.F., A.C., M. Hubli, J.R.), Balgrist University Hospital, University of Zurich, Switzerland; International Collaboration on Repair Discoveries (ICORD) (J.L.K.K.), Department of Anesthesiology, Pharmacology, and Therapeutics, Faculty of Medicine (J.L.K.K.), University of British Columbia, Vancouver, Canada; Department of Biosystems Science and Technology (C.R.J.), Swiss Federal Institute of Technology Zurich, Switzerland; Wellcome Centre for Human Neuroimaging (P.F.), UCL Institute of Neurology, UCL, London, UK; Department of Neurophysics (P.F.), Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; and Department of Neurology (J.R.), University Hospital Bern, Inselspital, University of Bern, Switzerland
| | - Gergely David
- From the Spinal Cord Injury Center (P.S.S., G.D., M. Hupp, P.F., A.C., M. Hubli, J.R.), Balgrist University Hospital, University of Zurich, Switzerland; International Collaboration on Repair Discoveries (ICORD) (J.L.K.K.), Department of Anesthesiology, Pharmacology, and Therapeutics, Faculty of Medicine (J.L.K.K.), University of British Columbia, Vancouver, Canada; Department of Biosystems Science and Technology (C.R.J.), Swiss Federal Institute of Technology Zurich, Switzerland; Wellcome Centre for Human Neuroimaging (P.F.), UCL Institute of Neurology, UCL, London, UK; Department of Neurophysics (P.F.), Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; and Department of Neurology (J.R.), University Hospital Bern, Inselspital, University of Bern, Switzerland
| | - John Lawrence Kipling Kramer
- From the Spinal Cord Injury Center (P.S.S., G.D., M. Hupp, P.F., A.C., M. Hubli, J.R.), Balgrist University Hospital, University of Zurich, Switzerland; International Collaboration on Repair Discoveries (ICORD) (J.L.K.K.), Department of Anesthesiology, Pharmacology, and Therapeutics, Faculty of Medicine (J.L.K.K.), University of British Columbia, Vancouver, Canada; Department of Biosystems Science and Technology (C.R.J.), Swiss Federal Institute of Technology Zurich, Switzerland; Wellcome Centre for Human Neuroimaging (P.F.), UCL Institute of Neurology, UCL, London, UK; Department of Neurophysics (P.F.), Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; and Department of Neurology (J.R.), University Hospital Bern, Inselspital, University of Bern, Switzerland
| | - Catherine Ruth Jutzeler
- From the Spinal Cord Injury Center (P.S.S., G.D., M. Hupp, P.F., A.C., M. Hubli, J.R.), Balgrist University Hospital, University of Zurich, Switzerland; International Collaboration on Repair Discoveries (ICORD) (J.L.K.K.), Department of Anesthesiology, Pharmacology, and Therapeutics, Faculty of Medicine (J.L.K.K.), University of British Columbia, Vancouver, Canada; Department of Biosystems Science and Technology (C.R.J.), Swiss Federal Institute of Technology Zurich, Switzerland; Wellcome Centre for Human Neuroimaging (P.F.), UCL Institute of Neurology, UCL, London, UK; Department of Neurophysics (P.F.), Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; and Department of Neurology (J.R.), University Hospital Bern, Inselspital, University of Bern, Switzerland
| | - Markus Hupp
- From the Spinal Cord Injury Center (P.S.S., G.D., M. Hupp, P.F., A.C., M. Hubli, J.R.), Balgrist University Hospital, University of Zurich, Switzerland; International Collaboration on Repair Discoveries (ICORD) (J.L.K.K.), Department of Anesthesiology, Pharmacology, and Therapeutics, Faculty of Medicine (J.L.K.K.), University of British Columbia, Vancouver, Canada; Department of Biosystems Science and Technology (C.R.J.), Swiss Federal Institute of Technology Zurich, Switzerland; Wellcome Centre for Human Neuroimaging (P.F.), UCL Institute of Neurology, UCL, London, UK; Department of Neurophysics (P.F.), Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; and Department of Neurology (J.R.), University Hospital Bern, Inselspital, University of Bern, Switzerland
| | - Patrick Freund
- From the Spinal Cord Injury Center (P.S.S., G.D., M. Hupp, P.F., A.C., M. Hubli, J.R.), Balgrist University Hospital, University of Zurich, Switzerland; International Collaboration on Repair Discoveries (ICORD) (J.L.K.K.), Department of Anesthesiology, Pharmacology, and Therapeutics, Faculty of Medicine (J.L.K.K.), University of British Columbia, Vancouver, Canada; Department of Biosystems Science and Technology (C.R.J.), Swiss Federal Institute of Technology Zurich, Switzerland; Wellcome Centre for Human Neuroimaging (P.F.), UCL Institute of Neurology, UCL, London, UK; Department of Neurophysics (P.F.), Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; and Department of Neurology (J.R.), University Hospital Bern, Inselspital, University of Bern, Switzerland
| | - Armin Curt
- From the Spinal Cord Injury Center (P.S.S., G.D., M. Hupp, P.F., A.C., M. Hubli, J.R.), Balgrist University Hospital, University of Zurich, Switzerland; International Collaboration on Repair Discoveries (ICORD) (J.L.K.K.), Department of Anesthesiology, Pharmacology, and Therapeutics, Faculty of Medicine (J.L.K.K.), University of British Columbia, Vancouver, Canada; Department of Biosystems Science and Technology (C.R.J.), Swiss Federal Institute of Technology Zurich, Switzerland; Wellcome Centre for Human Neuroimaging (P.F.), UCL Institute of Neurology, UCL, London, UK; Department of Neurophysics (P.F.), Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; and Department of Neurology (J.R.), University Hospital Bern, Inselspital, University of Bern, Switzerland
| | - Michèle Hubli
- From the Spinal Cord Injury Center (P.S.S., G.D., M. Hupp, P.F., A.C., M. Hubli, J.R.), Balgrist University Hospital, University of Zurich, Switzerland; International Collaboration on Repair Discoveries (ICORD) (J.L.K.K.), Department of Anesthesiology, Pharmacology, and Therapeutics, Faculty of Medicine (J.L.K.K.), University of British Columbia, Vancouver, Canada; Department of Biosystems Science and Technology (C.R.J.), Swiss Federal Institute of Technology Zurich, Switzerland; Wellcome Centre for Human Neuroimaging (P.F.), UCL Institute of Neurology, UCL, London, UK; Department of Neurophysics (P.F.), Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; and Department of Neurology (J.R.), University Hospital Bern, Inselspital, University of Bern, Switzerland
| | - Jan Rosner
- From the Spinal Cord Injury Center (P.S.S., G.D., M. Hupp, P.F., A.C., M. Hubli, J.R.), Balgrist University Hospital, University of Zurich, Switzerland; International Collaboration on Repair Discoveries (ICORD) (J.L.K.K.), Department of Anesthesiology, Pharmacology, and Therapeutics, Faculty of Medicine (J.L.K.K.), University of British Columbia, Vancouver, Canada; Department of Biosystems Science and Technology (C.R.J.), Swiss Federal Institute of Technology Zurich, Switzerland; Wellcome Centre for Human Neuroimaging (P.F.), UCL Institute of Neurology, UCL, London, UK; Department of Neurophysics (P.F.), Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; and Department of Neurology (J.R.), University Hospital Bern, Inselspital, University of Bern, Switzerland.
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24
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Huynh V, Lütolf R, Rosner J, Luechinger R, Curt A, Kollias S, Hubli M, Michels L. Supraspinal nociceptive networks in neuropathic pain after spinal cord injury. Hum Brain Mapp 2021; 42:3733-3749. [PMID: 34132441 PMCID: PMC8288099 DOI: 10.1002/hbm.25401] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 02/18/2021] [Accepted: 02/22/2021] [Indexed: 12/13/2022] Open
Abstract
Neuropathic pain following spinal cord injury involves plastic changes along the whole neuroaxis. Current neuroimaging studies have identified grey matter volume (GMV) and resting-state functional connectivity changes of pain processing regions related to neuropathic pain intensity in spinal cord injury subjects. However, the relationship between the underlying neural processes and pain extent, a complementary characteristic of neuropathic pain, is unknown. We therefore aimed to reveal the neural markers of widespread neuropathic pain in spinal cord injury subjects and hypothesized that those with greater pain extent will show higher GMV and stronger connectivity within pain related regions. Thus, 29 chronic paraplegic subjects and 25 healthy controls underwent clinical and electrophysiological examinations combined with neuroimaging. Paraplegics were demarcated based on neuropathic pain and were thoroughly matched demographically. Our findings indicate that (a) spinal cord injury subjects with neuropathic pain display stronger connectivity between prefrontal cortices and regions involved with sensory integration and multimodal processing, (b) greater neuropathic pain extent, is associated with stronger connectivity between the posterior insular cortex and thalamic sub-regions which partake in the lateral pain system and (c) greater intensity of neuropathic pain is related to stronger connectivity of regions involved with multimodal integration and the affective-motivational component of pain. Overall, this study provides neuroimaging evidence that the pain phenotype of spinal cord injury subjects is related to the underlying function of their resting brain.
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Affiliation(s)
- Vincent Huynh
- Department of Neuroradiology, Clinical Neuroscience CenterUniversity Hospital Zurich & University of ZurichZurichSwitzerland
- Spinal Cord Injury CenterBalgrist University Hospital, University of ZurichZurichSwitzerland
| | - Robin Lütolf
- Spinal Cord Injury CenterBalgrist University Hospital, University of ZurichZurichSwitzerland
| | - Jan Rosner
- Spinal Cord Injury CenterBalgrist University Hospital, University of ZurichZurichSwitzerland
- Department of Neurology, InselspitalBern University Hospital, University of BernBernSwitzerland
| | - Roger Luechinger
- Institute for Biomedical EngineeringUniversity and ETH ZürichZürichSwitzerland
| | - Armin Curt
- Spinal Cord Injury CenterBalgrist University Hospital, University of ZurichZurichSwitzerland
| | - Spyridon Kollias
- Department of Neuroradiology, Clinical Neuroscience CenterUniversity Hospital Zurich & University of ZurichZurichSwitzerland
| | - Michèle Hubli
- Spinal Cord Injury CenterBalgrist University Hospital, University of ZurichZurichSwitzerland
| | - Lars Michels
- Department of Neuroradiology, Clinical Neuroscience CenterUniversity Hospital Zurich & University of ZurichZurichSwitzerland
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25
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Rosner J, Negraeff M, Bélanger LM, Tsang A, Ritchie L, Mac-Thiong JM, Christie S, Wilson JR, Dhall S, Charest-Morin R, Street J, Ailon T, Paquette S, Dea N, Fisher CG, Dvorak MF, Finnerup NB, Kwon BK, Kramer JLK. Characterization of Hyperacute Neuropathic Pain after Spinal Cord Injury: A Prospective Study. J Pain 2021; 23:89-97. [PMID: 34302956 DOI: 10.1016/j.jpain.2021.06.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Revised: 06/19/2021] [Accepted: 06/25/2021] [Indexed: 10/20/2022]
Abstract
There is currently a lack of information regarding neuropathic pain in the very early stages of spinal cord injury (SCI). In the present study, neuropathic pain was assessed using the Douleur Neuropathique 4 Questions (DN4) for the patient's worst pain within the first 5 days of injury (i.e., hyperacute) and on follow-up at 3, 6, and 12 months. Within the hyperacute time frame (i.e., 5 days), at- and below-level neuropathic pain were reported as the worst pain in 23% (n = 18) and 5% (n = 4) of individuals with SCI, respectively. Compared to the neuropathic pain observed in this hyperacute setting, late presenting neuropathic pain was characterized by more intense painful electrical and cold sensations, but less itching sensations. Phenotypic differences between acute and late neuropathic pain support the incorporation of timing into a mechanism-based classification of neuropathic pain after SCI. The diagnosis of acute neuropathic pain after SCI is challenged by the presence of nociceptive and neuropathic pains, with the former potentially masking the latter. This may lead to an underestimation of the incidence of neuropathic pain during the very early, hyperacute time points post-injury. TRIAL REGISTRATION: ClinicalTrials.gov (Identifier: NCT01279811) PERSPECTIVE: This article presents distinct pain phenotypes of hyperacute and late presenting neuropathic pain after spinal cord injury and highlights the challenges of pain assessments in the acute phase after injury. This information may be relevant to clinical trial design and broaden our understanding of neuropathic pain mechanisms after spinal cord injury.
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Affiliation(s)
- Jan Rosner
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada; Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland; Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Michael Negraeff
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada; Department of Anesthesiology, Pharmacology, and Therapeutics, Faculty of Medicine, University of British Columbia, British Columbia, Canada
| | - Lise M Bélanger
- Vancouver Spine Program, Vancouver General Hospital, Vancouver, British Columbia, Canada
| | - Angela Tsang
- Vancouver Spine Program, Vancouver General Hospital, Vancouver, British Columbia, Canada
| | - Leanna Ritchie
- Vancouver Spine Program, Vancouver General Hospital, Vancouver, British Columbia, Canada
| | - Jean-Marc Mac-Thiong
- Hôpital du Sacré-Coeur de Montréal, Montréal, Quebec, Canada; Faculty of Medicine, Université de Montréal, Montréal, Quebec, Canada
| | - Sean Christie
- Division of Neurosurgery, Department of Surgery, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Jefferson R Wilson
- Division of Neurosurgery, Department of Surgery, University of Toronto, St Michael's Hospital, Toronto, Ontario, Canada
| | - Sanjay Dhall
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, California
| | - Raphaële Charest-Morin
- Vancouver Spine Surgery Institute, Department of Orthopaedics, University of British Columbia, Vancouver, British Columbia, Canada
| | - John Street
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada; Vancouver Spine Surgery Institute, Department of Orthopaedics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Tamir Ailon
- Division of Neurosurgery, University of British Columbia, Vancouver, British Columbia, Canada
| | - Scott Paquette
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada; Division of Neurosurgery, University of British Columbia, Vancouver, British Columbia, Canada
| | - Nicolas Dea
- Division of Neurosurgery, University of British Columbia, Vancouver, British Columbia, Canada
| | - Charles G Fisher
- Vancouver Spine Surgery Institute, Department of Orthopaedics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Marcel F Dvorak
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada; Vancouver Spine Surgery Institute, Department of Orthopaedics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Nanna B Finnerup
- Danish Pain Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; Department of Neurology, Aarhus University Hospital, Aarhus, Denmark
| | - Brian K Kwon
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada; Vancouver Spine Surgery Institute, Department of Orthopaedics, University of British Columbia, Vancouver, British Columbia, Canada
| | - John L K Kramer
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada; Department of Anesthesiology, Pharmacology, and Therapeutics, Faculty of Medicine, University of British Columbia, British Columbia, Canada.
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26
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Kyathanahally SP, Azzarito M, Rosner J, Calhoun VD, Blaiotta C, Ashburner J, Weiskopf N, Wiech K, Friston K, Ziegler G, Freund P. Microstructural plasticity in nociceptive pathways after spinal cord injury. J Neurol Neurosurg Psychiatry 2021; 92:jnnp-2020-325580. [PMID: 34039630 PMCID: PMC8292587 DOI: 10.1136/jnnp-2020-325580] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 03/12/2021] [Accepted: 04/21/2021] [Indexed: 12/26/2022]
Abstract
OBJECTIVE To track the interplay between (micro-) structural changes along the trajectories of nociceptive pathways and its relation to the presence and intensity of neuropathic pain (NP) after spinal cord injury (SCI). METHODS A quantitative neuroimaging approach employing a multiparametric mapping protocol was used, providing indirect measures of myelination (via contrasts such as magnetisation transfer (MT) saturation, longitudinal relaxation (R1)) and iron content (via effective transverse relaxation rate (R2*)) was used to track microstructural changes within nociceptive pathways. In order to characterise concurrent changes along the entire neuroaxis, a combined brain and spinal cord template embedded in the statistical parametric mapping framework was used. Multivariate source-based morphometry was performed to identify naturally grouped patterns of structural variation between individuals with and without NP after SCI. RESULTS In individuals with NP, lower R1 and MT values are evident in the primary motor cortex and dorsolateral prefrontal cortex, while increases in R2* are evident in the cervical cord, periaqueductal grey (PAG), thalamus and anterior cingulate cortex when compared with pain-free individuals. Lower R1 values in the PAG and greater R2* values in the cervical cord are associated with NP intensity. CONCLUSIONS The degree of microstructural changes across ascending and descending nociceptive pathways is critically implicated in the maintenance of NP. Tracking maladaptive plasticity unravels the intimate relationships between neurodegenerative and compensatory processes in NP states and may facilitate patient monitoring during therapeutic trials related to pain and neuroregeneration.
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Affiliation(s)
- Sreenath P Kyathanahally
- Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland
| | - Michela Azzarito
- Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland
| | - Jan Rosner
- Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland
- Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Vince D Calhoun
- Tri-institutional Center for Translational Research in Neuroimaging and Data Science (TReNDS): Georgia State University, Georgia Institute of Technology, Emory University, Atlanta, Georgia, USA
| | - Claudia Blaiotta
- Wellcome Centre for Human Neuroimaging, UCL Institute of Neurology, UCL, London, UK
| | - John Ashburner
- Wellcome Centre for Human Neuroimaging, UCL Institute of Neurology, UCL, London, UK
| | - Nikolaus Weiskopf
- Neurophysics, Max-Planck-Institut fur Kognitions- und Neurowissenschaften, Leipzig, Germany
| | - Katja Wiech
- Wellcome Centre for Integrative Neuroimaging (WIN), Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Karl Friston
- Wellcome Centre for Human Neuroimaging, UCL Institute of Neurology, UCL, London, UK
| | - Gabriel Ziegler
- German Center for Neurodegenerative Disease (DZNE), Magdeburg, Germany
| | - Patrick Freund
- Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland
- Wellcome Centre for Human Neuroimaging, UCL Institute of Neurology, UCL, London, UK
- Neurophysics, Max-Planck-Institut fur Kognitions- und Neurowissenschaften, Leipzig, Germany
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27
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Sirucek L, Jutzeler CR, Rosner J, Schweinhardt P, Curt A, Kramer JLK, Hubli M. The Effect of Conditioned Pain Modulation on Tonic Heat Pain Assessed Using Participant-Controlled Temperature. Pain Med 2021; 21:2839-2849. [PMID: 32176283 DOI: 10.1093/pm/pnaa041] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
OBJECTIVE Descending pain modulation can be experimentally assessed by way of testing conditioned pain modulation. The application of tonic heat as a test stimulus in such paradigms offers the possibility of observing dynamic pain responses, such as adaptation and temporal summation of pain. Here we investigated conditioned pain modulation effects on tonic heat employing participant-controlled temperature, an alternative tonic heat pain assessment. Changes in pain perception are thereby represented by temperature adjustments performed by the participant, uncoupling this approach from direct pain ratings. Participant-controlled temperature has emerged as a reliable and sex-independent measure of tonic heat. METHODS Thirty healthy subjects underwent a sequential conditioned pain modulation paradigm, in which a cold water bath was applied as the conditioning stimulus and tonic heat as a test stimulus. Subjects were instructed to change the temperature of the thermode in response to variations in perception to tonic heat in order to maintain their initial rating over a two-minute period. Two additional test stimuli (i.e., lower limb noxious withdrawal reflex and pressure pain threshold) were included as positive controls for conditioned pain modulation effects. RESULTS Participant-controlled temperature revealed conditioned pain modulation effects on temporal summation of pain (P = 0.01). Increased noxious withdrawal reflex thresholds (P = 0.004) and pressure pain thresholds (P < 0.001) in response to conditioning also confirmed inhibitory conditioned pain modulation effects. CONCLUSIONS The measured interaction between conditioned pain modulation and temporal summation of pain supports the participant-controlled temperature approach as a promising method to explore dynamic inhibitory and facilitatory pain processes previously undetected by rating-based approaches.
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Affiliation(s)
- Laura Sirucek
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.,Integrative Spinal Research Group, Department of Chiropractic Medicine, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Catherine Ruth Jutzeler
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.,International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada.,School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.,School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Petra Schweinhardt
- Integrative Spinal Research Group, Department of Chiropractic Medicine, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Armin Curt
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - John Lawrence Kipling Kramer
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada.,School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Michèle Hubli
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
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Rosner J, Lütolf R, Hostettler P, Villiger M, Clijsen R, Hohenauer E, Barbero M, Curt A, Hubli M. Assessment of neuropathic pain after spinal cord injury using quantitative pain drawings. Spinal Cord 2021; 59:529-537. [PMID: 33594250 PMCID: PMC8110478 DOI: 10.1038/s41393-021-00616-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 01/17/2021] [Accepted: 01/22/2021] [Indexed: 11/09/2022]
Abstract
STUDY DESIGN Clinimetric cross-sectional cohort study in adults with paraplegic spinal cord injury (SCI) and neuropathic pain (NP). OBJECTIVE To assess the reliability of standardized quantitative pain drawings in patients with NP following SCI. SETTING Hospital-based research facility at the Spinal Cord Injury Center, Balgrist University Hospital, Zurich, Switzerland. METHODS Twenty individuals with chronic thoracic spinal cord injury and neuropathic pain were recruited from a national and local SCI registry. A thorough clinical examination and pain assessments were performed. Pain drawings were acquired at subsequent timepoints, 13 days (IQR 7.8-14.8) apart, in order to assess test-retest reliability. RESULTS The average extent [%] and intensity [NRS 0-10] of spontaneous NP were 11.3% (IQR 4.9-35.8) and 5 (IQR 3-7), respectively. Pain extent showed excellent inter-session reliability (intraclass correlation coefficient 0.96). Sensory loss quantified by light touch and pinprick sensation was associated with larger pain extent (rpinprick = -0.47, p = 0.04; rlight touch = -0.64, p < 0.01). CONCLUSION Assessing pain extent using quantitative pain drawings is readily feasible and reliable in human SCI. Relating information of sensory deficits to the presence of pain may provide distinct insights into the interaction of sensory deafferentation and the development of neuropathic pain after SCI.
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Affiliation(s)
- Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.
- Department of Neurology, Bern University Hospital, Inselspital, University of Bern, Bern, Switzerland.
| | - Robin Lütolf
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Pascal Hostettler
- Department of Neurology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Michael Villiger
- Department of Sports Medicine, Davos Hospital, Davos, Switzerland
| | - Ron Clijsen
- Rehabilitation Research Laboratory 2rLab, Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Manno/Landquart, Switzerland
- International University of Applied Sciences THIM, Landquart, Switzerland
| | - Erich Hohenauer
- Rehabilitation Research Laboratory 2rLab, Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Manno/Landquart, Switzerland
- International University of Applied Sciences THIM, Landquart, Switzerland
- Department of Neurosciences and Movement Science, University of Fribourg, Fribourg, Switzerland
| | - Marco Barbero
- Rehabilitation Research Laboratory 2rLab, Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Manno/Landquart, Switzerland
| | - Armin Curt
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Michèle Hubli
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
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29
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Rosner J, Scheuren PS, Stalder SA, Curt A, Hubli M. Pinprick Evoked Potentials-Reliable Acquisition in Healthy Human Volunteers. Pain Med 2021; 21:736-746. [PMID: 31216028 DOI: 10.1093/pm/pnz126] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
OBJECTIVE Pinprick evoked potentials (PEPs) represent a novel tool to assess the functional integrity of mechano-nociceptive pathways with a potential toward objectifying sensory deficits and gain seen in neurological disorders. The aim of the present study was to evaluate the feasibility and reliability of PEPs with respect to age, stimulation site, and skin type. METHODS Electroencephalographic responses evoked by two pinprick stimulation intensities (128 mN and 256 mN) applied at three sites (hand dorsum, palmar digit II, and foot dorsum) were recorded in 30 healthy individuals. Test-retest reliability was performed for the vertex negative-positive complex amplitudes, N-latencies, and pain ratings evoked by the 256mN stimulation intensity. RESULTS Feasibility of PEP acquisition was demonstrated across age groups, with higher proportions of evoked potentials (>85%) for the 256mN stimulation intensity. Reliability analyses, that is, Bland-Altman and intraclass correlation coefficients, revealed poor to excellent reliability upon retest depending on the stimulation sites. CONCLUSIONS This study highlights the reliability of PEP acquisition from cervical and lumbar segments across clinically representative age groups. Future methodological improvements might further strengthen PEP reliability in order to complement clinical neurophysiology of sensory nerve fibers by a more specific assessment of mechano-nociceptive pathways. Beyond looking at sensory deficits, PEPs may also become applicable to revealing signs of central sensitization, complementing the clinical assessment of mechanical hyperalgesia.
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Affiliation(s)
- Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Paulina Simonne Scheuren
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Stephanie Anja Stalder
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Armin Curt
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Michèle Hubli
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
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30
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Hupp M, Pfender N, Vallotton K, Rosner J, Friedl S, Zipser CM, Sutter R, Klarhöfer M, Spirig JM, Betz M, Schubert M, Freund P, Farshad M, Curt A. The Restless Spinal Cord in Degenerative Cervical Myelopathy. AJNR Am J Neuroradiol 2021; 42:597-609. [PMID: 33541903 DOI: 10.3174/ajnr.a6958] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Accepted: 10/12/2020] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE The spinal cord is subject to a periodic, cardiac-related movement, which is increased at the level of a cervical stenosis. Increased oscillations may exert mechanical stress on spinal cord tissue causing intramedullary damage. Motion analysis thus holds promise as a biomarker related to disease progression in degenerative cervical myelopathy. Our aim was characterization of the cervical spinal cord motion in patients with degenerative cervical myelopathy. MATERIALS AND METHODS Phase-contrast MR imaging data were analyzed in 55 patients (37 men; mean age, 56.2 [SD,12.0] years; 36 multisegmental stenoses) and 18 controls (9 men, P = .368; mean age, 62.2 [SD, 6.5] years; P = .024). Parameters of interest included the displacement and motion pattern. Motion data were pooled on the segmental level for comparison between groups. RESULTS In patients, mean craniocaudal oscillations were increased manifold at any level of a cervical stenosis (eg, C5 displacement: controls [n = 18], 0.54 [SD, 0.16] mm; patients [n = 29], monosegmental stenosis [n = 10], 1.86 [SD, 0.92] mm; P < .001) and even in segments remote from the level of the stenosis (eg, C2 displacement: controls [n = 18], 0.36 [SD, 0.09] mm; patients [n = 52]; stenosis: C3, n = 21; C4, n = 11; C5, n = 18; C6, n = 2; 0.85 [SD, 0.46] mm; P < .001). Motion at C2 differed with the distance to the next stenotic segment and the number of stenotic segments. The motion pattern in most patients showed continuous spinal cord motion throughout the cardiac cycle. CONCLUSIONS Patients with degenerative cervical myelopathy show altered spinal cord motion with increased and ongoing oscillations at and also beyond the focal level of stenosis. Phase-contrast MR imaging has promise as a biomarker to reveal mechanical stress to the cord and may be applicable to predict disease progression and the impact of surgical interventions.
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Affiliation(s)
- M Hupp
- From the Spinal Cord Injury Center (M.H., N.P., K.V., J.R., S.F., C.M.Z., M.S., P.F., A.C.)
| | - N Pfender
- From the Spinal Cord Injury Center (M.H., N.P., K.V., J.R., S.F., C.M.Z., M.S., P.F., A.C.)
| | - K Vallotton
- From the Spinal Cord Injury Center (M.H., N.P., K.V., J.R., S.F., C.M.Z., M.S., P.F., A.C.)
| | - J Rosner
- From the Spinal Cord Injury Center (M.H., N.P., K.V., J.R., S.F., C.M.Z., M.S., P.F., A.C.).,Department of Neurology (J.R.), University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - S Friedl
- From the Spinal Cord Injury Center (M.H., N.P., K.V., J.R., S.F., C.M.Z., M.S., P.F., A.C.)
| | - C M Zipser
- From the Spinal Cord Injury Center (M.H., N.P., K.V., J.R., S.F., C.M.Z., M.S., P.F., A.C.)
| | | | - M Klarhöfer
- Siemens Healthcare AG (M.K.), Zurich, Switzerland
| | - J M Spirig
- University Spine Center Zurich (J.M.S., M.B., M.F., A.C.), Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - M Betz
- University Spine Center Zurich (J.M.S., M.B., M.F., A.C.), Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - M Schubert
- From the Spinal Cord Injury Center (M.H., N.P., K.V., J.R., S.F., C.M.Z., M.S., P.F., A.C.)
| | - P Freund
- From the Spinal Cord Injury Center (M.H., N.P., K.V., J.R., S.F., C.M.Z., M.S., P.F., A.C.)
| | - M Farshad
- University Spine Center Zurich (J.M.S., M.B., M.F., A.C.), Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - A Curt
- From the Spinal Cord Injury Center (M.H., N.P., K.V., J.R., S.F., C.M.Z., M.S., P.F., A.C.).,University Spine Center Zurich (J.M.S., M.B., M.F., A.C.), Balgrist University Hospital, University of Zurich, Zurich, Switzerland
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Hecker A, Aguirre J, Eichenberger U, Rosner J, Schubert M, Sutter R, Wieser K, Bouaicha S. Deltoid muscle contribution to shoulder flexion and abduction strength: an experimental approach. J Shoulder Elbow Surg 2021; 30:e60-e68. [PMID: 32540315 DOI: 10.1016/j.jse.2020.05.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 05/06/2020] [Accepted: 05/12/2020] [Indexed: 02/01/2023]
Abstract
BACKGROUND The rotator cuff (RC) and the deltoid muscle are 2 synergistic units that enable the functionally demanding movements of the shoulder. A number of biomechanical studies assume similar force contribution of the force couple (RC and deltoid) over the whole range of motion, whereas others propose position-dependent force distribution. There is a lack of in vivo data regarding the deltoid's contribution to shoulder flexion and abduction strength. This study aimed to create reliable in vivo data quantifying the deltoid's contribution to shoulder flexion and abduction strength throughout the range of motion. METHODS Active range of motion and isometric muscle strength of shoulder abduction and flexion in 0°, 30°, 60°, 90°, and 120° of abduction/flexion as well as internal and external rotation in 0° and 90° of abduction were obtained in 12 healthy volunteers on the dominant arm before and after an ultrasound-guided isolated axillary nerve block. Needle electromyography was performed before and after the block to confirm deltoid paralysis. Radiographs of the shoulder and an ultrasonographic examination were used to exclude relevant shoulder pathologies. RESULTS Active range of motion showed a minimal to moderate reduction to 94% and 88% of the preintervention value for abduction and flexion. Internal and external rotation amplitude was not impaired. The abduction strength was significantly reduced to 76% at 0° (P = .002) and to 25% at 120° (P < .001) of abduction. The flexion strength was significantly reduced to 64% at 30° (P < .001) and to 30% at 120° (P < .001) of flexion. The strength reduction was linear, depending on the flexion/abduction angle. The maximal external rotation strength showed a significant decrease to 53% in 90° (P < .001) of abduction, whereas in adduction no strength loss was observed (P = .09). The internal rotation strength remained unaffected in 0° and 90° of abduction (P = .28; P = .13). CONCLUSION The deltoid shows a linear contribution to maximal shoulder strength depending on the abduction or flexion angle, ranging from 24% in 0° to 75% in 120° of abduction and from 11% in 0° to 70% in 120° of flexion, respectively. The overall contribution to abduction strength is higher than to flexion strength. The combination of deltoid muscle and teres minor contributes about 50% to external rotation strength in 90° of abduction. The internal rotation strength is not influenced by a deltoid paralysis. This study highlights the position-dependent contribution of the shoulder muscles to strength development and thereby provides an empirical approach to better understand human shoulder kinematics.
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Affiliation(s)
- Andreas Hecker
- Department of Orthopedics, Balgrist University Hospital, University of Zürich, Zürich, Switzerland; Department of Orthopedics, Bern University Hospital, Inselspital, University of Bern, Bern, Switzerland.
| | - José Aguirre
- Department of Anesthesiology, Balgrist University Hospital, University of Zürich, Zürich, Switzerland
| | - Urs Eichenberger
- Department of Anesthesiology, Balgrist University Hospital, University of Zürich, Zürich, Switzerland
| | - Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zürich, Zürich, Switzerland; Department of Neurology, Bern University Hospital, Inselspital, University of Bern, Bern, Switzerland
| | - Martin Schubert
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zürich, Zürich, Switzerland
| | - Reto Sutter
- Department of Radiology, Balgrist University Hospital, University of Zürich, Zürich, Switzerland
| | - Karl Wieser
- Department of Orthopedics, Balgrist University Hospital, University of Zürich, Zürich, Switzerland
| | - Samy Bouaicha
- Department of Orthopedics, Balgrist University Hospital, University of Zürich, Zürich, Switzerland
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Marzoughi S, Banerjee A, Jutzeler CR, Prado MAM, Rosner J, Cragg JJ, Cashman N. Tardive neurotoxicity of anticholinergic drugs: A review. J Neurochem 2020; 158:1334-1344. [PMID: 33222198 DOI: 10.1111/jnc.15244] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 11/15/2020] [Accepted: 11/17/2020] [Indexed: 12/15/2022]
Abstract
The cholinergic system is a complex neurotransmitter system with functional involvement at multiple levels of the nervous system including the cerebral cortex, spinal cord, autonomic nervous system, and neuromuscular junction. Anticholinergic medications are among the most prescribed medications, making up one-third to one-half of all medications prescribed for seniors. Recent evidence has linked long-term use of anticholinergic medications and dementia. Emerging evidence implicates the cholinergic system in the regulation of cerebral vasculature as well as neuroinflammation, suggesting that anticholinergic medications may contribute to absolute risk and progression of neurodegenerative diseases. In this review, we explore the involvement of the cholinergic system in various neurodegenerative diseases and the possible detrimental effects of anticholinergic medications on the onset and progression of these disorders. We identified references by searching the PubMed and Cochrane database between January 1990 and September 2019 for English-language animal and human studies including randomized clinical trials (RCTs), meta-analyses, systematic reviews, and observational studies. In addition, we conducted a manual search of reference lists from retrieved studies. Long-term anticholinergic medication exposure may have detrimental consequences beyond well-documented short-term cognitive effects, through a variety of mechanisms either directly impacting cholinergic neurotransmission or through receptors expressed on the vasculature or immune cells, providing a pathophysiological framework for complex interactions across the entire neuroaxis.
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Affiliation(s)
- Sina Marzoughi
- Division of Neurology, Department of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Ankur Banerjee
- Department of Medicine, University of Calgary, Calgary, AB, Canada
| | - Catherine R Jutzeler
- Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland
| | - Marco A M Prado
- Robarts Research Institute, The University of Western Ontario, London, ON, Canada
| | - Jan Rosner
- Collaboration for Outcomes Research and Evaluation (CORE), Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Jacquelyn J Cragg
- Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland
| | - Neil Cashman
- Division of Neurology, Department of Medicine, University of British Columbia, Vancouver, BC, Canada
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Jutzeler CR, Linde LD, Rosner J, Hubli M, Curt A, Kramer JLK. Single-trial averaging improves the physiological interpretation of contact heat evoked potentials. Neuroimage 2020; 225:117473. [PMID: 33099013 DOI: 10.1016/j.neuroimage.2020.117473] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 09/12/2020] [Accepted: 10/14/2020] [Indexed: 10/23/2022] Open
Abstract
Laser and contact heat evoked potentials (LEPs and CHEPs, respectively) provide an objective measure of pathways and processes involved in nociception. The majority of studies analyzing LEP or CHEP outcomes have done so based on conventional, across-trial averaging. With this approach, evoked potential components are potentially confounded by latency jitter and ignore relevant information contained within single trials. The current study addressed the advantage of analyzing nociceptive evoked potentials based on responses to noxious stimulations within each individual trial. Single-trial and conventional averaging were applied to data previously collected in 90 healthy subjects from 3 stimulation locations on the upper limb. The primary analysis focused on relationships between single and across-trial averaged CHEP outcomes (i.e., N2P2 amplitude and N2 and P2 latencies) and subject characteristics (i.e., age, sex, height, and rating of perceived intensity), which were examined by way of linear mixed model analysis. Single-trial averaging lead to larger N2P2 amplitudes and longer N2 and P2 latencies. Age and ratings of perceived intensity were the only subject level characteristics associated with CHEPs outcomes that significantly interacted with the method of analysis (conventional vs single-trial averaging). The strength of relationships for age and ratings of perceived intensity, measured by linear fit, were increased for single-trial compared to conventional across-trial averaged CHEP outcomes. By accounting for latency jitter, single-trial averaging improved the associations between CHEPs and physiological outcomes and should be incorporated as a standard analytical technique in future studies.
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Affiliation(s)
- Catherine R Jutzeler
- Swiss Federal Institute of Technology (ETH Zurich), Department of Biosystems Science and Engineering, Mattenstrasse 26, 4058 Basel, Switzerland; SIB Swiss Institute of Bioinformatics, Switzerland; Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland.
| | - Lukas D Linde
- ICORD, University of British Columbia, 818W 10th Ave, Vancouver, British Columbia, Canada; Department of Anesthesiology, Pharmacology & Therapeutics, Faculty of Medicine, University of British Columbia, 818W 10th Ave, Vancouver, British Columbia, Canada; Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 818W 10th Ave, Vancouver, British Columbia, Canada
| | - Jan Rosner
- Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland; Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Michèle Hubli
- Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland
| | - Armin Curt
- Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland
| | - John L K Kramer
- ICORD, University of British Columbia, 818W 10th Ave, Vancouver, British Columbia, Canada; Department of Anesthesiology, Pharmacology & Therapeutics, Faculty of Medicine, University of British Columbia, 818W 10th Ave, Vancouver, British Columbia, Canada; Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 818W 10th Ave, Vancouver, British Columbia, Canada.
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Scheuren PS, Rosner J, Curt A, Hubli M. Pain-autonomic interaction: A surrogate marker of central sensitization. Eur J Pain 2020; 24:2015-2026. [PMID: 32794307 DOI: 10.1002/ejp.1645] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 08/05/2020] [Accepted: 08/06/2020] [Indexed: 11/07/2022]
Abstract
BACKGROUND Central sensitization represents a key pathophysiological mechanism underlying the development of neuropathic pain, often manifested clinically as mechanical allodynia and hyperalgesia. Adopting a mechanism-based treatment approach relies highly on the ability to assess the presence of central sensitization. The aim of the study was to investigate potential pain-autonomic readouts to operationalize experimentally induced central sensitization in the area of secondary hyperalgesia. METHODS Pinprick evoked potentials (PEPs) and sympathetic skin responses (SSRs) were recorded in 20 healthy individuals. Three blocks of PEP and SSR recordings were performed before and after heat-induced secondary hyperalgesia. All measurements were also performed before and after a control condition. Multivariate analyses were performed using linear mixed-effect regression models to examine the effect of experimentally induced central sensitization on PEP and SSR parameters (i.e. amplitudes, latencies and habituation) and on pinprick pain ratings. RESULTS The noxious heat stimulation induced robust mechanical hyperalgesia with a significant increase in PEP and SSR amplitudes (p < 0.001) in the area of secondary hyperalgesia. Furthermore, PEP and SSR habituation were reduced (p < 0.001) after experimentally induced central sensitization. CONCLUSIONS The findings demonstrate that combined recordings of PEPs and SSRs are sensitive to objectify experimentally induced central sensitization and may have a great potential to reveal its presence in clinical pain conditions. Corroborating current pain phenotyping with pain-autonomic markers has the potential to unravel central sensitization along the nociceptive neuraxis and might provide a framework for mechanistically founded therapies. SIGNIFICANCE Our findings provide evidence that combined recordings of sympathetic skin responses (SSRs) and pinprick evoked potentials (PEPs) might be able to unmask central sensitization induced through a well-established experimental pain model in healthy individuals. As such, these novel readouts of central sensitization might attain new insights towards complementing clinical pain phenotyping.
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Affiliation(s)
- Paulina S Scheuren
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.,Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Armin Curt
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Michèle Hubli
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
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Abstract
The purpose of the study described in this article was to determine the accuracy of parents in identifying strabismus (disorder of eye in which optic axis cannot be directed to same object) in their young children. Data are presented on 536 children (84 strabismics and 452 non-strabismics), aged 3–71 months, that show parents to be remarkably good detectors of strabismus. The predictive value of their positive tests was 93 percent; sensitivity, 65 percent; and specificity, 99 percent.
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Affiliation(s)
- J. Rosner
- College of Optometry, University of Houston, Houston, TX 77004
| | - J. Rosner
- College of Optometry, University of Houston, Houston, TX 77004
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Liu LJW, Rosner J, Cragg JJ. Journal Club: High-dose methylprednisolone for acute traumatic spinal cord injury: A meta-analysis. Neurology 2020; 95:272-274. [PMID: 32269114 DOI: 10.1212/wnl.0000000000009263] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Affiliation(s)
- Lisa J W Liu
- From the Faculty of Pharmaceutical Sciences (L.J.W.L., J.R., J.J.C.) and International Collaboration on Repair Discoveries (ICORD) (L.J.W.L., J.J.C.), University of British Columbia, Vancouver, Canada; Spinal Cord Injury Center (J.R.), Balgrist University Hospital, University of Zurich; and Department of Neurology (J.R.), University Hospital Bern, Inselspital, University of Bern, Switzerland
| | - Jan Rosner
- From the Faculty of Pharmaceutical Sciences (L.J.W.L., J.R., J.J.C.) and International Collaboration on Repair Discoveries (ICORD) (L.J.W.L., J.J.C.), University of British Columbia, Vancouver, Canada; Spinal Cord Injury Center (J.R.), Balgrist University Hospital, University of Zurich; and Department of Neurology (J.R.), University Hospital Bern, Inselspital, University of Bern, Switzerland
| | - Jacquelyn J Cragg
- From the Faculty of Pharmaceutical Sciences (L.J.W.L., J.R., J.J.C.) and International Collaboration on Repair Discoveries (ICORD) (L.J.W.L., J.J.C.), University of British Columbia, Vancouver, Canada; Spinal Cord Injury Center (J.R.), Balgrist University Hospital, University of Zurich; and Department of Neurology (J.R.), University Hospital Bern, Inselspital, University of Bern, Switzerland.
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Huynh V, Rosner J, Curt A, Kollias S, Hubli M, Michels L. Disentangling the Effects of Spinal Cord Injury and Related Neuropathic Pain on Supraspinal Neuroplasticity: A Systematic Review on Neuroimaging. Front Neurol 2020; 10:1413. [PMID: 32116986 PMCID: PMC7013003 DOI: 10.3389/fneur.2019.01413] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 12/27/2019] [Indexed: 12/11/2022] Open
Abstract
Background: Spinal cord injury (SCI) and its accompanying changes of brain structure and function have been widely studied and reviewed. Debilitating chronic neuropathic pain (NP) is reported in 53% of SCI patients, and brain changes have been shown to be involved with the presence of this secondary complication. However, there is yet a synthesis of current studies that investigated brain structure, resting connectivity, and metabolite changes that accompanies this condition. Methods: In this review, a systematic search was performed using Medical Subject Headings heading search terms in PubMed and SCOPUS to gather the appropriate published studies. Neuroimaging studies that investigated supraspinal structural, resting-state connectivity, and metabolite changes in SCI subjects with NP were included. To this end, voxel-based morphometry, diffusion tensor imaging, resting-state functional MRI, magnetic resonance spectroscopy, and PET studies were summarized and reviewed. Further inclusion and exclusion criteria allowed delineation of appropriate studies that included SCI subgroups with and without NP. Results: A total of 12 studies were eligible for qualitative synthesis. Overall, current studies that investigated NP-associated changes within the SCI cohort show primarily metabolite concentration alterations in sensory-pain processing regions, alongside bidirectional changes of brain structure. Moreover, in comparison to healthy controls, there remains limited evidence of structural and connectivity changes but a range of alterations in metabolite concentrations in SCI subjects with NP. Conclusions: There is some evidence suggesting that the magnitude and presence of NP following SCI results in both adaptive and maladaptive structural plasticity of sensorimotor regions, alongside altered metabolism of brain areas involved with descending pain modulation, pain perception (i.e., anterior cingulate cortex) and sensory integration (i.e., thalamus). However, based on the fact that only a few studies investigated structural and glucose metabolic changes in chronic SCI subjects with NP, the underlying mechanisms that accompany this condition remains to be further elucidated. Future cross-sectional or longitudinal studies that aim to disentangle NP related to SCI may benefit from stricter constraints in subject cohorts, controlled subgroups, improved pain phenotyping, and implementation of multimodal approaches to discover sensitive biomarkers that profile pain and optimize treatment in SCI subjects with NP.
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Affiliation(s)
- Vincent Huynh
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.,Department of Neuroradiology, University Hospital Zurich, Zurich, Switzerland
| | - Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.,Department of Neurology, Bern University Hospital (Inselspital), University of Bern, Bern, Switzerland
| | - Armin Curt
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Spyros Kollias
- Department of Neuroradiology, University Hospital Zurich, Zurich, Switzerland
| | - Michèle Hubli
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Lars Michels
- Department of Neuroradiology, University Hospital Zurich, Zurich, Switzerland.,MR-Center, University Children's Hospital Zurich, Zurich, Switzerland
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Linde LD, Haefeli J, Jutzeler CR, Rosner J, McDougall J, Curt A, Kramer JLK. Contact Heat Evoked Potentials Are Responsive to Peripheral Sensitization: Requisite Stimulation Parameters. Front Hum Neurosci 2020; 13:459. [PMID: 31998104 PMCID: PMC6966714 DOI: 10.3389/fnhum.2019.00459] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 12/16/2019] [Indexed: 12/20/2022] Open
Abstract
The sensitizing effect of capsaicin has been previously characterized using laser and contact heat evoked potentials (LEPs and CHEPs) by stimulating in the primary area of hyperalgesia. Interestingly, only CHEPs reveal changes consistent with notion of peripheral sensitization (i.e., reduced latencies). The aim of this study was to investigate contact heat stimulation parameters necessary to detect peripheral sensitization related to the topical application of capsaicin, and therefore significantly improve the current method of measuring peripheral sensitization via CHEPs. Rapid contact heat stimulation (70°C/s) was applied from three different baseline temperatures (35, 38.5, and 42°C) to a 52°C peak temperature, before and after the topical application of capsaicin on the hand dorsum. Increased pain ratings in the primary area of hyperalgesia were accompanied by reduced N2 latency. Changes in N2 latency were, however, only significant following stimulation from 35 and 38.5°C baseline temperatures. These findings suggest that earlier recruitment of capsaicin-sensitized afferents occurs between 35 and 42°C, as stimulations from 42°C baseline were unchanged by capsaicin. This is in line with reduced thresholds of type II A-delta mechanoheat (AMH) nociceptors following sensitization. Conventional CHEP stimulation, with a baseline temperature below 42°C, is well suited to objectively detect evidence of peripheral sensitization.
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Affiliation(s)
- Lukas D Linde
- ICORD, The University of British Columbia, Vancouver, BC, Canada.,School of Kinesiology, The University of British Columbia, Vancouver, BC, Canada
| | - Jenny Haefeli
- Brain and Spinal Injury Center, Department of Neurosurgery, University of California, San Francisco, San Francisco, CA, United States
| | - Catherine R Jutzeler
- ICORD, The University of British Columbia, Vancouver, BC, Canada.,School of Kinesiology, The University of British Columbia, Vancouver, BC, Canada.,Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.,Department of Neurology, University Hospital Bern, Inselspital, University of Bern, Bern, Switzerland
| | - Jessica McDougall
- ICORD, The University of British Columbia, Vancouver, BC, Canada.,School of Rehabilitation Sciences, Faculty of Medicine, The University of British Columbia, Vancouver, BC, Canada
| | - Armin Curt
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - John L K Kramer
- ICORD, The University of British Columbia, Vancouver, BC, Canada.,School of Kinesiology, The University of British Columbia, Vancouver, BC, Canada
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Rosner J, Scheuren P, Hupp M, Curt A, Hubli M. FV 6 Characterization of spinothalamic tract lesions using multi-modal neurophysiology. Clin Neurophysiol 2019. [DOI: 10.1016/j.clinph.2019.04.616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Jutzeler CR, Sirucek L, Scheuren PS, Bobo T, Anenberg E, Ortiz O, Rosner J, Hubli M, Kramer JLK. New life for an old idea: Assessing tonic heat pain by means of participant controlled temperature. J Neurosci Methods 2019; 321:20-27. [PMID: 30959080 DOI: 10.1016/j.jneumeth.2019.04.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 03/20/2019] [Accepted: 04/05/2019] [Indexed: 10/27/2022]
Abstract
BACKGROUND Temporal changes of pain perception to prolonged tonic heat pain are conventionally assessed using a computerized visual analog scale. Such a rating-based approach is, however, prone to floor and ceiling effects, which limit the assessment of temporal changes in perception. Thus, alternative methods that overcome these shortcomings are warranted. NEW METHOD The aim of this study was to assess the feasibility and reliability of a psychophysical approach, i.e., participant-controlled temperature (PCT), to evaluate ongoing human perception of tonic heat pain. Fifty participants were presented with a 45 °C stimulus on the non-dominant hand, and were instructed to maintain their initial sensation for two minutes via a feedback controller in the dominant hand. A subset of participants (n = 17) performed PCT tonic heat protocols on two different days to determine the test-retest reliability. As participants controlled temperature to maintain a stable pain perception, any adjustments made reflected shifts in their perception of heat. RESULTS In 33 (71.7%) participants, we observed an initial adaptation (participant increased temperature) followed by temporal summation of pain (participant decreased temperature). Twelve participants (26.1%) showed only adaptation and one (2.2%) only temporal summation. No sex differences were observed, nor did the initial rating of pain have an effect on PCT outcomes. Temporal summation of pain showed moderate to substantial reliability upon retest. CONCLUSIONS PCT represents can be reliably performed using a contact heat stimulator to measure the temporal summation of pain. The standardized setup and overall good reliability of the outcome measures facilitate a sound implementation into the clinical work-up of patients with pain conditions.
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Affiliation(s)
- Catherine R Jutzeler
- Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland; ICORD, University of British Columbia, Vancouver, British Columbia, Canada; School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada.
| | - Laura Sirucek
- Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland.
| | - Paulina S Scheuren
- ICORD, University of British Columbia, Vancouver, British Columbia, Canada.
| | - Tong Bobo
- ICORD, University of British Columbia, Vancouver, British Columbia, Canada.
| | - Eitan Anenberg
- ICORD, University of British Columbia, Vancouver, British Columbia, Canada.
| | - Oscar Ortiz
- ICORD, University of British Columbia, Vancouver, British Columbia, Canada.
| | - Jan Rosner
- Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland.
| | - Michèle Hubli
- Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland.
| | - John L K Kramer
- ICORD, University of British Columbia, Vancouver, British Columbia, Canada; School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada.
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David G, Seif M, Huber E, Hupp M, Rosner J, Dietz V, Weiskopf N, Mohammadi S, Freund P. In vivo evidence of remote neural degeneration in the lumbar enlargement after cervical injury. Neurology 2019; 92:e1367-e1377. [PMID: 30770423 PMCID: PMC6511094 DOI: 10.1212/wnl.0000000000007137] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 11/07/2018] [Indexed: 01/14/2023] Open
Abstract
OBJECTIVE To characterize remote secondary neurodegeneration of spinal tracts and neurons below a cervical spinal cord injury (SCI) and its relation to the severity of injury, the integrity of efferent and afferent pathways, and clinical impairment. METHODS A comprehensive high-resolution MRI protocol was acquired in 17 traumatic cervical SCI patients and 14 controls at 3T. At the cervical lesion, a sagittal T2-weighted scan provided information on the width of preserved midsagittal tissue bridges. In the lumbar enlargement, high-resolution T2*-weighted and diffusion-weighted scans were used to calculate tissue-specific cross-sectional areas and diffusion indices, respectively. Regression analyses determined associations between MRI readouts and the electrophysiologic and clinical measures. RESULTS At the cervical injury level, preserved midsagittal tissue bridges were present in the majority of patients. In the lumbar enlargement, neurodegeneration-in terms of macrostructural and microstructural MRI changes-was evident in the white matter and ventral and dorsal horns. Patients with thinner midsagittal tissue bridges had smaller ventral horn area, higher radial diffusivity in the gray matter, smaller motor evoked potential amplitude from the lower extremities, and lower motor score. In addition, smaller width of midsagittal tissue bridges was also associated with smaller tibialis sensory evoked potential amplitude and lower light-touch score. CONCLUSIONS This study shows extensive tissue-specific cord pathology in infralesional spinal networks following cervical SCI, its magnitude relating to lesion severity, electrophysiologic integrity, and clinical impairment of the lower extremity. The clinical eloquence of remote neurodegenerative changes speaks to the application of neuroimaging biomarkers in diagnostic workup and planning of clinical trials.
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Affiliation(s)
- Gergely David
- From the Spinal Cord Injury Center Balgrist (G.D., M.S., E.H., M.H., J.R., V.D., P.F.), University Hospital Zurich, University of Zurich, Switzerland; Wellcome Trust Centre for Neuroimaging (N.W., S.M., P.F.), UCL Institute of Neurology, London, UK; Department of Neurophysics (M.S., N.W., P.F.), Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig; and Department of Systems Neuroscience (S.M.), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Maryam Seif
- From the Spinal Cord Injury Center Balgrist (G.D., M.S., E.H., M.H., J.R., V.D., P.F.), University Hospital Zurich, University of Zurich, Switzerland; Wellcome Trust Centre for Neuroimaging (N.W., S.M., P.F.), UCL Institute of Neurology, London, UK; Department of Neurophysics (M.S., N.W., P.F.), Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig; and Department of Systems Neuroscience (S.M.), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Eveline Huber
- From the Spinal Cord Injury Center Balgrist (G.D., M.S., E.H., M.H., J.R., V.D., P.F.), University Hospital Zurich, University of Zurich, Switzerland; Wellcome Trust Centre for Neuroimaging (N.W., S.M., P.F.), UCL Institute of Neurology, London, UK; Department of Neurophysics (M.S., N.W., P.F.), Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig; and Department of Systems Neuroscience (S.M.), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Markus Hupp
- From the Spinal Cord Injury Center Balgrist (G.D., M.S., E.H., M.H., J.R., V.D., P.F.), University Hospital Zurich, University of Zurich, Switzerland; Wellcome Trust Centre for Neuroimaging (N.W., S.M., P.F.), UCL Institute of Neurology, London, UK; Department of Neurophysics (M.S., N.W., P.F.), Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig; and Department of Systems Neuroscience (S.M.), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jan Rosner
- From the Spinal Cord Injury Center Balgrist (G.D., M.S., E.H., M.H., J.R., V.D., P.F.), University Hospital Zurich, University of Zurich, Switzerland; Wellcome Trust Centre for Neuroimaging (N.W., S.M., P.F.), UCL Institute of Neurology, London, UK; Department of Neurophysics (M.S., N.W., P.F.), Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig; and Department of Systems Neuroscience (S.M.), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Volker Dietz
- From the Spinal Cord Injury Center Balgrist (G.D., M.S., E.H., M.H., J.R., V.D., P.F.), University Hospital Zurich, University of Zurich, Switzerland; Wellcome Trust Centre for Neuroimaging (N.W., S.M., P.F.), UCL Institute of Neurology, London, UK; Department of Neurophysics (M.S., N.W., P.F.), Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig; and Department of Systems Neuroscience (S.M.), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Nikolaus Weiskopf
- From the Spinal Cord Injury Center Balgrist (G.D., M.S., E.H., M.H., J.R., V.D., P.F.), University Hospital Zurich, University of Zurich, Switzerland; Wellcome Trust Centre for Neuroimaging (N.W., S.M., P.F.), UCL Institute of Neurology, London, UK; Department of Neurophysics (M.S., N.W., P.F.), Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig; and Department of Systems Neuroscience (S.M.), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Siawoosh Mohammadi
- From the Spinal Cord Injury Center Balgrist (G.D., M.S., E.H., M.H., J.R., V.D., P.F.), University Hospital Zurich, University of Zurich, Switzerland; Wellcome Trust Centre for Neuroimaging (N.W., S.M., P.F.), UCL Institute of Neurology, London, UK; Department of Neurophysics (M.S., N.W., P.F.), Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig; and Department of Systems Neuroscience (S.M.), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Patrick Freund
- From the Spinal Cord Injury Center Balgrist (G.D., M.S., E.H., M.H., J.R., V.D., P.F.), University Hospital Zurich, University of Zurich, Switzerland; Wellcome Trust Centre for Neuroimaging (N.W., S.M., P.F.), UCL Institute of Neurology, London, UK; Department of Neurophysics (M.S., N.W., P.F.), Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig; and Department of Systems Neuroscience (S.M.), University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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Scheuren PS, Gagné M, Jutzeler CR, Rosner J, Mercier C, Kramer JLK. Tracking Changes in Neuropathic Pain After Acute Spinal Cord Injury. Front Neurol 2019; 10:90. [PMID: 30837931 PMCID: PMC6382744 DOI: 10.3389/fneur.2019.00090] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 01/23/2019] [Indexed: 11/22/2022] Open
Abstract
Neuropathic pain represents a primary detrimental outcome of spinal cord injury. A major challenge facing effective management is a lack of surrogate measures to examine the physiology and anatomy of neuropathic pain. To this end, we investigated the relationship between psychophysical responses to tonic heat stimulation and neuropathic pain rating after traumatic spinal cord injury. Subjects provided a continuous rating to 2 min of tonic heat at admission to rehabilitation and again at discharge. Adaptation, temporal summation of pain, and modulation profile (i.e., the relationship between adaptation and temporal summation of pain) were extracted from tonic heat curves for each subject. There was no association between any of the tonic heat outcomes and neuropathic pain severity at admission. The degree of adaptation, the degree of temporal summation of pain, and the modulation profile did not change significantly from admission to discharge. However, changes in modulation profiles between admission and discharge were significantly correlated with changes in neuropathic pain severity (p = 0.027; R2 = 0.323). The modulation profile may represent an effective measure to track changes in neuropathic pain severity from early to later stages of spinal cord injury.
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Affiliation(s)
- Paulina Simonne Scheuren
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, BC, Canada.,Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland.,Department of Health Sciences and Technology, Swiss Federal Institute of Technology, Zurich, Switzerland
| | - Martin Gagné
- The Interdisciplinary Center for Research in Rehabilitation and Social Integration, Quebec, QC, Canada
| | - Catherine Ruth Jutzeler
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, BC, Canada.,School of Kinesiology, University of British Columbia, Vancouver, BC, Canada
| | - Jan Rosner
- Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland
| | - Catherine Mercier
- The Interdisciplinary Center for Research in Rehabilitation and Social Integration, Quebec, QC, Canada.,Department of Rehabilitation, Laval University, Quebec, QC, Canada
| | - John Lawrence Kipling Kramer
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, BC, Canada.,School of Kinesiology, University of British Columbia, Vancouver, BC, Canada
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Rosner J, Rinert J, Ernst M, Curt A, Hubli M. Cold evoked potentials: Acquisition from cervical dermatomes. Neurophysiol Clin 2019; 49:49-57. [DOI: 10.1016/j.neucli.2018.11.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 11/26/2018] [Accepted: 11/26/2018] [Indexed: 01/06/2023] Open
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Rosner J, Hubli M, Hostettler P, Jutzeler CR, Kramer JLK, Curt A. Not Hot, but Sharp: Dissociation of Pinprick and Heat Perception in Snake Eye Appearance Myelopathy. Front Neurol 2019; 9:1144. [PMID: 30622512 PMCID: PMC6308139 DOI: 10.3389/fneur.2018.01144] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 12/11/2018] [Indexed: 11/19/2022] Open
Abstract
Following a traumatic spinal cord injury, a 53-year-old male developed a central cord syndrome with at-level neuropathic pain. Magnetic resonance imaging revealed a classical “snake eye” appearance myelopathy, with marked hyperintensities at C5-C7. Clinical examination revealed intact pinprick sensation coupled with lost or diminished thermal/heat sensation. This dissociation could be objectively confirmed through multi-modal neurophysiological assessments. Specifically, contact heat evoked potentials were lost at-level, while pinprick evoked potentials were preserved. This pattern corresponds with that seen after surgical commissural myelotomy. To our knowledge, this is the first time such a dissociation has been objectively documented, highlighting the diagnostic potential of multi-modal neurophysiological assessments. In future studies, a comprehensive assessment of different nociceptive modalities may help elucidate the pathophysiology of neuropathic pain.
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Affiliation(s)
- Jan Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Michèle Hubli
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Pascal Hostettler
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Catherine R Jutzeler
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.,International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, BC, Canada
| | - John L K Kramer
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, BC, Canada
| | - Armin Curt
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
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Rosner J, Hubli M, Hostettler P, Scheuren PS, Rinert J, Kramer JLK, Hupp M, Curt A, Jutzeler CR. Contact heat evoked potentials: Reliable acquisition from lower extremities. Clin Neurophysiol 2018; 129:584-591. [PMID: 29414402 DOI: 10.1016/j.clinph.2017.12.034] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 11/28/2017] [Accepted: 12/17/2017] [Indexed: 12/27/2022]
Abstract
OBJECTIVE To investigate test-retest reliability of contact heat evoked potentials (CHEPs) from lower extremities using two different stimulation protocols, i.e., normal and increased baseline temperature. METHODS A total of 32 able-bodied subjects were included and a subset (N = 22) was retested. CHEPs were recorded from three different dermatomes of the lower extremity (i.e., L2, L5, and S2). Test-retest reliability of CHEPs acquisition after simulation in various lower limb dermatomes using different stimulation protocols was analyzed. RESULTS The study revealed an improved acquisition of CHEPS employing the increased baseline protocol, particularly when stimulating more distal sites, i.e., dermatome L5 and S2. Based on repeatability coefficients, CHEP latency (N2 potential) emerged as the most robust CHEP parameter. Although CHEP amplitudes (N2P2 complex) and pain ratings were decreased in the retest, amplitudes still showed fair to excellent intraclass correlation coefficients using normal baseline or increased baseline temperature, respectively. CONCLUSIONS This is the first study to demonstrate that CHEPs acquisition from the lower extremities is improved by increasing the baseline temperature of the thermode. SIGNIFICANCE This study highlights the usability of CHEPs as a viable diagnostic method to study small fiber integrity.
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Affiliation(s)
- J Rosner
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - M Hubli
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.
| | - P Hostettler
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - P S Scheuren
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
| | - J Rinert
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - J L K Kramer
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada; School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - M Hupp
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - A Curt
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - C R Jutzeler
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland; International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
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Jutzeler CR, Ulrich A, Huber B, Rosner J, Kramer JL, Curt A. Improved Diagnosis of Cervical Spondylotic Myelopathy with Contact Heat Evoked Potentials. J Neurotrauma 2017; 34:2045-2053. [DOI: 10.1089/neu.2016.4891] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
| | - Anett Ulrich
- Spinal Cord Injury Center, University Hospital Balgrist, Zurich, Switzerland
| | - Barbara Huber
- Spinal Cord Injury Center, University Hospital Balgrist, Zurich, Switzerland
| | - Jan Rosner
- Spinal Cord Injury Center, University Hospital Balgrist, Zurich, Switzerland
| | - John L.K. Kramer
- ICORD, University of British Columbia, Vancouver, British Columbia, Canada
| | - Armin Curt
- Spinal Cord Injury Center, University Hospital Balgrist, Zurich, Switzerland
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Jutzeler CR, Rosner J, Rinert J, Kramer JLK, Curt A. Normative data for the segmental acquisition of contact heat evoked potentials in cervical dermatomes. Sci Rep 2016; 6:34660. [PMID: 27708413 PMCID: PMC5052572 DOI: 10.1038/srep34660] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 09/13/2016] [Indexed: 01/04/2023] Open
Abstract
Contact heat evoked potentials (CHEPs) represent a neurophysiological approach to assess conduction in the spinothalamic tract. The aim of this study was to establish normative values of CHEPs acquired from cervical dermatomes (C4, C6, C8) and examine the potential confounds of age, sex, and height. 101 (49 male) healthy subjects of three different age groups (18–40, 41–60, and 61–80 years) were recruited. Normal (NB, 35–52 °C) followed by increased (IB, 42–52 °C) baseline stimulation protocols were employed to record CHEPs. Multi-variate linear models were used to investigate the effect of age, sex, and height on the CHEPs parameters (i.e., N2 latency, N2P2 amplitude, rating of perceived intensity). Compared to NB, IB stimulation reduced latency jitter within subjects, yielding larger N2P2 amplitudes, and decreased inter-subject N2 latency variability. Age was associated with reduced N2P2 amplitude and prolonged N2 latency. After controlling for height, male subjects had significantly longer N2 latencies than females during IB stimulation. The study provides normative CHEPs data in a large cohort of healthy subjects from segmentally examined cervical dermatomes. Age and sex were identified as important factors contributing to N2 latency and N2P2 amplitude. The normative data will improve the diagnosis of spinal cord pathologies.
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Affiliation(s)
- Catherine R Jutzeler
- Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland.,ICORD, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jan Rosner
- Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland
| | - Janosch Rinert
- Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland
| | - John L K Kramer
- ICORD, University of British Columbia, Vancouver, British Columbia, Canada.,School of Kinesiology, University of British Columbia, Vancouver, BC, Canada
| | - Armin Curt
- Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland
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Killeen T, Rosner J, Jutzeler CR, Hupp M, Heilbronner R, Curt A. Spontaneous resolution of an extensive posttraumatic syrinx. Neurology 2016; 87:1299-301. [PMID: 27543642 DOI: 10.1212/wnl.0000000000003130] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 06/07/2016] [Indexed: 11/15/2022] Open
Affiliation(s)
- Tim Killeen
- From the Spinal Cord Injury Center (T.K., J.R., C.R.J., M.H., A.C.), University Hospital Balgrist, Zurich; Cantonal Hospital St. Gallen (T.K., R.H.), Switzerland; and ICORD (C.R.J.), University of British Columbia, Vancouver, Canada.
| | - Jan Rosner
- From the Spinal Cord Injury Center (T.K., J.R., C.R.J., M.H., A.C.), University Hospital Balgrist, Zurich; Cantonal Hospital St. Gallen (T.K., R.H.), Switzerland; and ICORD (C.R.J.), University of British Columbia, Vancouver, Canada
| | - Catherine R Jutzeler
- From the Spinal Cord Injury Center (T.K., J.R., C.R.J., M.H., A.C.), University Hospital Balgrist, Zurich; Cantonal Hospital St. Gallen (T.K., R.H.), Switzerland; and ICORD (C.R.J.), University of British Columbia, Vancouver, Canada
| | - Markus Hupp
- From the Spinal Cord Injury Center (T.K., J.R., C.R.J., M.H., A.C.), University Hospital Balgrist, Zurich; Cantonal Hospital St. Gallen (T.K., R.H.), Switzerland; and ICORD (C.R.J.), University of British Columbia, Vancouver, Canada
| | - Raoul Heilbronner
- From the Spinal Cord Injury Center (T.K., J.R., C.R.J., M.H., A.C.), University Hospital Balgrist, Zurich; Cantonal Hospital St. Gallen (T.K., R.H.), Switzerland; and ICORD (C.R.J.), University of British Columbia, Vancouver, Canada
| | - Armin Curt
- From the Spinal Cord Injury Center (T.K., J.R., C.R.J., M.H., A.C.), University Hospital Balgrist, Zurich; Cantonal Hospital St. Gallen (T.K., R.H.), Switzerland; and ICORD (C.R.J.), University of British Columbia, Vancouver, Canada
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Abstract
It is shown that Meso-Inositol Hexanicotinate (MIHN; Hexopal) inhibits experimentally induced oedema of the paw in rats and that mice exposed to hypoxic atmospheres (4% oxygen) show significant increase in survival time if pre-dosed with MIHN. The protection against oedema and hypoxia conferred by MIHN in experimental animals may well be related to the mode of action of the substance in man, and particularly could explain the usefulness of MIHN in the treatment of cerebral and peripheral atherosclerosis.
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Affiliation(s)
- J Rosner
- Centre de Recherche, Laboratoires Winthrop SA, Dijon, France
| | - J Legros
- Centre de Recherche, Laboratoires Winthrop SA, Dijon, France
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Rosner J, Pfau D, Jutzeler C, Curt A, Treede RD, Greffrath W. P31. Using cold evoked potentials (CEPs) to assess spinothalamic function in healthy volunteers and patients with spinal cord injuries: A pilot study. Clin Neurophysiol 2015. [DOI: 10.1016/j.clinph.2015.04.169] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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