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Scheffler MS, Martin CA, Dietz V, Faraji AH, Sayenko DG. Synergistic implications of combinatorial rehabilitation approaches using spinal stimulation on therapeutic outcomes in spinal cord injury. Clin Neurophysiol 2024; 165:166-179. [PMID: 39033698 PMCID: PMC11325878 DOI: 10.1016/j.clinph.2024.06.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 06/07/2024] [Accepted: 06/26/2024] [Indexed: 07/23/2024]
Abstract
OBJECTIVE The objective of this narrative review was to locate and assess recent articles employing a combinatorial approach of transcutaneous spinal cord stimulation or epidural spinal cord stimulation with additional modalities. We sought to provide relevant knowledge of recent literature and advance understanding on outcomes reported, to better equip those working in neurorehabilitation and neuromodulation. METHODS Articles were selected and analyzed based on study approach, stimulation parameters, outcome measures, and presence of neurophysiological data to support findings. RESULTS This narrative review analyzed 44 recent articles employing a combinatorial approach of transcutaneous spinal cord stimulation or epidural spinal cord stimulation with additional modalities. Our findings showed that limited research exists regarding such combinatorial approaches, particularly when considering modalities beyond activity-based training. There is also limited consistency in neurophysiological and quality of life outcomes. CONCLUSION Articles involving transcutaneous spinal cord stimulation or epidural spinal cord stimulation with other modalities are limited in the current body of literature. Authors noted variety in approach, sample size, and use of participant perspective. Opportunities are present to add high quality research to this body of literature. SIGNIFICANCE Transcutaneous spinal cord stimulation and epidural spinal cord stimulation are emerging in research as viable avenues for targeting improvement of function after traumatic spinal cord injury, particularly when combined with activity-based training. This body of literature demonstrates viable areas for growth from both neurophysiological and functional perspectives. Further, exploration of novel combinatorial approaches holds potential to offer enhanced contributions to clinical and neurophysiological rehabilitation and research.
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Affiliation(s)
- Michelle S Scheffler
- Department of Neurosurgery, Houston Methodist Research Institute, 6670 Bertner Ave, Houston, TX, 77030, USA
| | - Catherine A Martin
- Department of Neurosurgery, Houston Methodist Research Institute, 6670 Bertner Ave, Houston, TX, 77030, USA
| | - Valerie Dietz
- Department of Neurosurgery, Houston Methodist Research Institute, 6670 Bertner Ave, Houston, TX, 77030, USA
| | - Amir H Faraji
- Department of Neurosurgery, Houston Methodist Research Institute, 6670 Bertner Ave, Houston, TX, 77030, USA
| | - Dimitry G Sayenko
- Department of Neurosurgery, Houston Methodist Research Institute, 6670 Bertner Ave, Houston, TX, 77030, USA.
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Martino Cinnera A, Bonanno M, Calabrò RS, Bisirri A, D'Arienzo M, D'Acunto A, Ciancarelli I, Morone G, Koch G. Paired associative stimulation to enhance motor outcome in spinal cord injury: a systematic review of first evidence. Expert Rev Med Devices 2024:1-12. [PMID: 38768088 DOI: 10.1080/17434440.2024.2358048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Accepted: 05/17/2024] [Indexed: 05/22/2024]
Abstract
INTRODUCTION Spinal cord injuries (SCI) often result in motor impairment and lifelong disability. METHODS This systematic review, conducted in agreement with PRISMA guidelines, aimed to evaluate the effects of cortico-spinal paired associative stimulation (PAS) on motor outcomes in individuals with SCI. PubMed, Scopus/EMBASE, Pedro, and Cochrane databases were consulted from inception to 2023/01/12. RESULTS In 1021 articles, 10 studies involving 84 patients meet the inclusion criteria, 7 case series/study, and 3 clinical trials. Despite light differences, the included studies performed a cortico-peripheral PAS using a single transcranial magnetic stimulation and high frequency electrical peripheral nerve stimulation for a consistent number of sessions (>20). All included studies reported improvement in motor outcomes recorded via clinical and/or neurophysiological assessment. CONCLUSION Available evidence showed an increase in motor outcomes after PAS stimulation. Indeed, both clinical and neurophysiological outcomes suggest the effectiveness of a high number of PAS sessions in chronic individuals with SCI. Due to a limited number of studies and an unsatisfactory study design, well-designed RCTs are needed to confirm the potentiality of these approaches and clarify the adequate dose-response of PAS in the SCI population. REGISTRATION ID The protocol was registered on the PROSPERO database (CRD42023485703).
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Affiliation(s)
- Alex Martino Cinnera
- Scientific Institute for Research, Hospitalisation and Health Care IRCCS Santa Lucia Foundation, Rome, Italy
| | | | | | | | - Martina D'Arienzo
- Scientific Institute for Research, Hospitalisation and Health Care IRCCS Santa Lucia Foundation, Rome, Italy
| | - Alessia D'Acunto
- Department of Neurosciences, Paediatric neurology, University of Rome Tor Vergata, Rome, Italy
| | - Irene Ciancarelli
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy
| | - Giovanni Morone
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy
- San Raffaele Institute of Sulmona, Sulmona, Italy
| | - Giacomo Koch
- Department of Neuroscience and Rehabilitation, University of Ferrara, Ferrara, Italy
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Tajali S, Balbinot G, Pakosh M, Sayenko DG, Zariffa J, Masani K. Modulations in neural pathways excitability post transcutaneous spinal cord stimulation among individuals with spinal cord injury: a systematic review. Front Neurosci 2024; 18:1372222. [PMID: 38591069 PMCID: PMC11000807 DOI: 10.3389/fnins.2024.1372222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Accepted: 03/06/2024] [Indexed: 04/10/2024] Open
Abstract
Introduction Transcutaneous spinal cord stimulation (TSCS), a non-invasive form of spinal cord stimulation, has been shown to improve motor function in individuals living with spinal cord injury (SCI). However, the effects of different types of TSCS currents including direct current (DC-TSCS), alternating current (AC-TSCS), and spinal paired stimulation on the excitability of neural pathways have not been systematically investigated. The objective of this systematic review was to determine the effects of TSCS on the excitability of neural pathways in adults with non-progressive SCI at any level. Methods The following databases were searched from their inception until June 2022: MEDLINE ALL, Embase, Web of Science, Cochrane Library, and clinical trials. A total of 4,431 abstracts were screened, and 23 articles were included. Results Nineteen studies used TSCS at the thoracolumbar enlargement for lower limb rehabilitation (gait & balance) and four studies used cervical TSCS for upper limb rehabilitation. Sixteen studies measured spinal excitability by reporting different outcomes including Hoffmann reflex (H-reflex), flexion reflex excitability, spinal motor evoked potentials (SMEPs), cervicomedullay evoked potentials (CMEPs), and cutaneous-input-evoked muscle response. Seven studies measured corticospinal excitability using motor evoked potentials (MEPs) induced by transcranial magnetic stimulation (TMS), and one study measured somatosensory evoked potentials (SSEPs) following TSCS. Our findings indicated a decrease in the amplitude of H-reflex and long latency flexion reflex following AC-TSCS, alongside an increase in the amplitudes of SMEPs and CMEPs. Moreover, the application of the TSCS-TMS paired associative technique resulted in spinal reflex inhibition, manifested by reduced amplitudes in both the H-reflex and flexion reflex arc. In terms of corticospinal excitability, findings from 5 studies demonstrated an increase in the amplitude of MEPs linked to lower limb muscles following DC-TSCS, in addition to paired associative stimulation involving repetitive TMS on the brain and DC-TSCS on the spine. There was an observed improvement in the latency of SSEPs in a single study. Notably, the overall quality of evidence, assessed by the modified Downs and Black Quality assessment, was deemed poor. Discussion This review unveils the systematic evidence supporting the potential of TSCS in reshaping both spinal and supraspinal neuronal circuitries post-SCI. Yet, it underscores the critical necessity for more rigorous, high-quality investigations.
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Affiliation(s)
- Shirin Tajali
- KITE Research Institute – University Health Network, Toronto, ON, Canada
| | - Gustavo Balbinot
- KITE Research Institute – University Health Network, Toronto, ON, Canada
- Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Center for Advancing Neurotechnological Innovation to Application – CRANIA, University Health Network, Toronto, ON, Canada
| | - Maureen Pakosh
- Library & Information Services, University Health Network, Toronto Rehabilitation Institute, ON, Canada
| | - Dimitry G. Sayenko
- Department of Neurosurgery, Center for Neuroregeneration, Houston Methodist Research Institute, Houston, TX, United States
| | - Jose Zariffa
- KITE Research Institute – University Health Network, Toronto, ON, Canada
- Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Toronto, ON, Canada
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- Rehabilitation Sciences Institute, University of Toronto, Toronto, ON, Canada
| | - Kei Masani
- KITE Research Institute – University Health Network, Toronto, ON, Canada
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
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Gordineer EA, Stokic DS, Krenn MJ. Distinguishing reflex from non-reflex responses elicited by transcutaneous spinal stimulation targeting the lumbosacral cord in healthy individuals. Exp Brain Res 2024:10.1007/s00221-024-06790-2. [PMID: 38416179 DOI: 10.1007/s00221-024-06790-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Accepted: 01/21/2024] [Indexed: 02/29/2024]
Abstract
Transcutaneous spinal stimulation (TSS) studies rely on the depolarization of afferent fibers to provide input to the spinal cord; however, this has not been routinely ascertained. Thus, we aimed to characterize the types of responses evoked by TSS and establish paired-pulse ratio cutoffs that distinguish posterior root reflexes, evoked by stimulation of afferent nerve fibers, from motor responses, evoked by stimulation of efferent nerve fibers. Twelve neurologically intact participants (six women) underwent unipolar TSS (cathode over T11-12 spinal processes, anode paraumbilically) while resting supine. In six participants, unipolar TSS was repeated 2-3 months later and also compared to a bipolar TSS configuration (cathode 2.5 cm below T11-12, anode 5 cm above cathode). EMG signals were recorded from 16 leg muscles. A paired-pulse paradigm was applied at interstimulus intervals (ISIs) of 25, 50, 100, 200, and 400 ms. Responses were categorized by three assessors into reflexes, motor responses, or their combination (mixed responses) based on the visual presence/absence of paired-pulse suppression across ISIs. The paired-pulse ratio that best discriminated between response types was derived for each ISI. These cutoffs were validated by repeating unipolar TSS 2-3 months later and with bipolar TSS. Unipolar TSS evoked only reflexes (90%) and mixed responses (10%), which were mainly recorded in the quadriceps muscles (25-42%). Paired-pulse ratios of 0.51 (25-ms ISI) and 0.47 (50-ms ISI) best distinguished reflexes from mixed responses (100% sensitivity, > 99.2% specificity). These cutoffs performed well in the repeated unipolar TSS session (100% sensitivity, > 89% specificity). Bipolar TSS exclusively elicited reflexes which were all correctly classified. These results can be utilized in future studies to ensure that the input to the spinal cord originates from the depolarization of large afferents. This knowledge can be applied to improve the design of future neurophysiological studies and increase the fidelity of neuromodulation interventions.
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Affiliation(s)
- Elizabeth A Gordineer
- School of Graduate Studies in the Health Sciences, Program in Neuroscience, University of Mississippi Medical Center, Jackson, MS, USA
- Center for Neuroscience and Neurological Recovery, Methodist Rehabilitation Center, Jackson, MS, USA
| | - Dobrivoje S Stokic
- Center for Neuroscience and Neurological Recovery, Methodist Rehabilitation Center, Jackson, MS, USA
| | - Matthias J Krenn
- Center for Neuroscience and Neurological Recovery, Methodist Rehabilitation Center, Jackson, MS, USA.
- Department of Neurosurgery, University of Mississippi Medical Center, 2500 N State St, Jackson, MS, 39216, USA.
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Martinez M. A bi-cortical neuroprosthesis to modulate locomotion after incomplete spinal cord injury. Sci Prog 2023; 106:368504231212788. [PMID: 38189274 PMCID: PMC10775731 DOI: 10.1177/00368504231212788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Neuroprosthetic strategies seek to immediately alleviate deficits and reinstate voluntary control of movement. To facilitate recovery, it is crucial to gain a comprehensive understanding of the mechanisms involved in the return of intentional movement. Nevertheless, the precise relationship between the resurgence of cortical commands and the recovery of locomotion remains somewhat elusive. In the study conducted by Duguay, Bonizzato, Delivet-Mongrain, Fortier-Lebel and Martinez, we introduced a neuroprosthesis designed to deliver precise bi-cortical stimulation in a clinically relevant contusive spinal cord injury model. We conducted experiments in both healthy and spinal cord injured cats, where we fine-tuned the timing, duration, amplitude, and site of stimulation to modulate hindlimb locomotor output. In healthy cats, we observed a wide range of motor programs. However, after spinal cord injury, the induced hindlimb movements became highly stereotyped but were effective in modulating gait and reducing bilateral foot dragging. These results suggest that the neural basis for motor recovery traded off selectivity for effectiveness. Through a series of longitudinal assessments, we found that the restoration of locomotion following spinal cord injury was closely linked to the recovery of the descending neural drive. This underscores the importance of directing rehabilitation interventions toward the cortical target. The study results are discussed in terms of their impact and limitations.
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Affiliation(s)
- Marina Martinez
- Marina Martinez, Département de neurosciences, Faculté de médecine, Université de Montréal, C.P. 6128, Succ. Centre-ville, Montréal, Québec, H3C 3J7, Canada.
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Abdullahi A, Wong TWL, Ng SSM. Variation in the rate of recovery in motor function between the upper and lower limbs in patients with stroke: some proposed hypotheses and their implications for research and practice. Front Neurol 2023; 14:1225924. [PMID: 37602245 PMCID: PMC10435271 DOI: 10.3389/fneur.2023.1225924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Accepted: 07/24/2023] [Indexed: 08/22/2023] Open
Abstract
Background Stroke results in impairment of motor function of both the upper and lower limbs. However, although it is debatable, motor function of the lower limb is believed to recover faster than that of the upper limb. The aim of this paper is to propose some hypotheses to explain the reasons for that, and discuss their implications for research and practice. Method We searched PubMED, Web of Science, Scopus, Embase and CENTRAL using the key words, stroke, cerebrovascular accident, upper extremity, lower extremity, and motor recovery for relevant literature. Result The search generated a total of 2,551 hits. However, out of this number, 51 duplicates were removed. Following review of the relevant literature, we proposed four hypotheses: natural instinct for walking hypothesis, bipedal locomotion hypothesis, central pattern generators (CPGs) hypothesis and role of spasticity hypothesis on the subject matter. Conclusion We opine that, what may eventually account for the difference, is the frequency of use of the affected limb or intensity of the rehabilitation intervention. This is because, from the above hypotheses, the lower limb seems to be used more frequently. When limbs are used frequently, this will result in use-dependent plasticity and eventual recovery. Thus, rehabilitation techniques that involve high repetitive tasks practice such as robotic rehabilitation, Wii gaming and constraint induced movement therapy should be used during upper limb rehabilitation.
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Van Steenbergen V, Burattini L, Trumpp M, Fourneau J, Aljović A, Chahin M, Oh H, D’Ambra M, Bareyre FM. Coordinated neurostimulation promotes circuit rewiring and unlocks recovery after spinal cord injury. J Exp Med 2023; 220:e20220615. [PMID: 36571760 PMCID: PMC9794600 DOI: 10.1084/jem.20220615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 10/26/2022] [Accepted: 12/15/2022] [Indexed: 12/27/2022] Open
Abstract
Functional recovery after incomplete spinal cord injury depends on the effective rewiring of neuronal circuits. Here, we show that selective chemogenetic activation of either corticospinal projection neurons or intraspinal relay neurons alone led to anatomically restricted plasticity and little functional recovery. In contrast, coordinated stimulation of both supraspinal centers and spinal relay stations resulted in marked and circuit-specific enhancement of neuronal rewiring, shortened EMG latencies, and improved locomotor recovery.
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Affiliation(s)
- Valérie Van Steenbergen
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
| | - Laura Burattini
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
| | - Michelle Trumpp
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
| | - Julie Fourneau
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
| | - Almir Aljović
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
- Graduate School of Systemic Neurosciences, LMU Munich, Planegg-Martinsried, Germany
| | - Maryam Chahin
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
- Graduate School of Systemic Neurosciences, LMU Munich, Planegg-Martinsried, Germany
| | - Hanseul Oh
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
- Graduate School of Systemic Neurosciences, LMU Munich, Planegg-Martinsried, Germany
| | - Marta D’Ambra
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
| | - Florence M. Bareyre
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
- Munich Cluster of Systems Neurology (SyNergy), LMU Munich, Munich, Germany
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Skiadopoulos A, Famodimu GO, Solomon SK, Agarwal P, Harel NY, Knikou M. Priming locomotor training with transspinal stimulation in people with spinal cord injury: study protocol of a randomized clinical trial. Trials 2023; 24:145. [PMID: 36841773 PMCID: PMC9960224 DOI: 10.1186/s13063-023-07193-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 02/20/2023] [Indexed: 02/27/2023] Open
Abstract
BACKGROUND The seemingly simple tasks of standing and walking require continuous integration of complex spinal reflex circuits between descending motor commands and ascending sensory inputs. Spinal cord injury greatly impairs standing and walking ability, but both improve with locomotor training. However, even after multiple locomotor training sessions, abnormal muscle activity and coordination persist. Thus, locomotor training alone cannot fully optimize the neuronal plasticity required to strengthen the synapses connecting the brain, spinal cord, and local circuits and potentiate neuronal activity based on need. Transcutaneous spinal cord (transspinal) stimulation alters motoneuron excitability over multiple segments by bringing motoneurons closer to threshold, a prerequisite for effectively promoting spinal locomotor network neuromodulation and strengthening neural connectivity of the injured human spinal cord. Importantly, whether concurrent treatment with transspinal stimulation and locomotor training maximizes motor recovery after spinal cord injury is unknown. METHODS Forty-five individuals with chronic spinal cord injury are receiving 40 sessions of robotic gait training primed with 30 Hz transspinal stimulation at the Thoracic 10 vertebral level. Participants are randomized to receive 30 min of active or sham transspinal stimulation during standing or active transspinal stimulation while supine followed by 30 min of robotic gait training. Over the course of locomotor training, the body weight support, treadmill speed, and leg guidance force are adjusted as needed for each participant based on absence of knee buckling during the stance phase and toe dragging during the swing phase. At baseline and after completion of all therapeutic sessions, neurophysiological recordings registering corticospinal and spinal neural excitability changes along with clinical assessment measures of standing and walking, and autonomic function via questionnaires regarding bowel, bladder, and sexual function are taken. DISCUSSION The results of this mechanistic randomized clinical trial will demonstrate that tonic transspinal stimulation strengthens corticomotoneuronal connectivity and dynamic neuromodulation through posture-dependent corticospinal and spinal neuroplasticity. We anticipate that this mechanistic clinical trial will greatly impact clinical practice because, in real-world clinical settings, noninvasive transspinal stimulation can be more easily and widely implemented than invasive epidural stimulation. Additionally, by applying multiple interventions to accelerate motor recovery, we are employing a treatment regimen that reflects a true clinical approach. TRIAL REGISTRATION ClinicalTrials.gov NCT04807764 . Registered on March 19, 2021.
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Affiliation(s)
- Andreas Skiadopoulos
- grid.254498.60000 0001 2198 5185Klab4Recovery Research Program, The City University of New York, College of Staten Island, Staten Island, NY USA ,grid.254498.60000 0001 2198 5185Department of Physical Therapy, College of Staten Island, The City University of New York, Staten Island, NY USA
| | - Grace O. Famodimu
- Spinal Cord Damage Research Center, James J. Peters Department of Veterans Affairs Medical Center, Bronx, NY USA
| | - Shammah K. Solomon
- grid.254498.60000 0001 2198 5185Klab4Recovery Research Program, The City University of New York, College of Staten Island, Staten Island, NY USA ,grid.254498.60000 0001 2198 5185Department of Physical Therapy, College of Staten Island, The City University of New York, Staten Island, NY USA
| | - Parul Agarwal
- grid.59734.3c0000 0001 0670 2351Population Health Science & Policy, Institute for Health Care Delivery Science, Icahn School of Medicine at Mount Sinai, Manhattan, NY USA
| | - Noam Y. Harel
- Spinal Cord Damage Research Center, James J. Peters Department of Veterans Affairs Medical Center, Bronx, NY USA ,grid.59734.3c0000 0001 0670 2351Population Health Science & Policy, Institute for Health Care Delivery Science, Icahn School of Medicine at Mount Sinai, Manhattan, NY USA
| | - Maria Knikou
- Klab4Recovery Research Program, The City University of New York, College of Staten Island, Staten Island, NY, USA. .,Department of Physical Therapy, College of Staten Island, The City University of New York, Staten Island, NY, USA. .,PhD Program in Biology and Collaborative Neuroscience Program, Graduate Center of The City University of New York and College of Staten Island, Manhattan & Staten Island, NY, USA.
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Skiadopoulos A, Famodimu GO, Solomon SK, Agrawal P, Harel NY, Knikou M. Priming locomotor training with transspinal stimulation in people with spinal cord injury: study protocol of a randomized clinical trial. RESEARCH SQUARE 2023:rs.3.rs-2527617. [PMID: 36824823 PMCID: PMC9949167 DOI: 10.21203/rs.3.rs-2527617/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Background The seemingly simple tasks of standing and walking require continuous integration of complex spinal reflex circuits between descending motor commands and ascending sensory inputs. Spinal cord injury greatly impairs standing and walking ability, but both improve with locomotor training. However, even after multiple locomotor training sessions, abnormal muscle activity and coordination persist. Thus, locomotor training alone cannot fully optimize the neuronal plasticity required to strengthen the synapses connecting the brain, spinal cord, and local circuits and potentiate neuronal activity based on need. Transcutaneous spinal cord (transspinal) stimulation alters motoneuron excitability over multiple segments by bringing motoneurons closer to threshold, a prerequisite for effectively promoting spinal locomotor network neuromodulation and strengthening neural connectivity of the injured human spinal cord. Importantly, whether concurrent treatment with transspinal stimulation and locomotor training maximizes motor recovery after spinal cord injury is unknown. Methods Forty-five individuals with chronic spinal cord injury are receiving 40 sessions of robotic gait training primed with 30 Hz transspinal stimulation at the Thoracic 10 vertebral level. Participants are randomized to receive 30-minutes of active or sham transspinal stimulation during standing or active transspinal stimulation while supine followed by 30-minutes of robotic gait training. Over the course of locomotor training, the body weight support, treadmill speed, and leg guidance force are adjusted as needed for each participant based on absence of knee buckling during the stance phase and toe dragging during the swing phase. At baseline and after completion of all therapeutic sessions, neurophysiological recordings registering corticospinal and spinal neural excitability changes along with clinical assessment measures of standing and walking, and autonomic function via questionnaires regarding bowel, bladder and sexual function are taken. Discussion The results of this mechanistic randomized clinical trial will demonstrate that tonic transspinal stimulation strengthens corticomotoneuronal connectivity and dynamic neuromodulation through posture-dependent corticospinal and spinal neuroplasticity. We anticipate that this mechanistic clinical trial will greatly impact clinical practice because in real-world clinical settings, noninvasive transspinal stimulation can be more easily and widely implemented than invasive epidural stimulation. Additionally, by applying multiple interventions to accelerate motor recovery, we are employing a treatment regimen that reflects a true clinical approach. Trial registration ClinicalTrials.gov: NCT04807764; Registered on March 19, 2021.
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Affiliation(s)
| | | | | | - Parul Agrawal
- Icahn School of Medicine at Mount Sinai Department of Population Health Science and Policy
| | - Noam Y Harel
- James J Peters VAMC: James J Peters VA Medical Center
| | - Maria Knikou
- College of Staten Island School of Health Sciences
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Neuromodulation with transcutaneous spinal stimulation reveals different groups of motor profiles during robot-guided stepping in humans with incomplete spinal cord injury. Exp Brain Res 2023; 241:365-382. [PMID: 36534141 PMCID: PMC10278039 DOI: 10.1007/s00221-022-06521-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 12/03/2022] [Indexed: 12/23/2022]
Abstract
Neuromodulation via spinal stimulation has been investigated for improving motor function and reducing spasticity after spinal cord injury (SCI) in humans. Despite the reported heterogeneity of outcomes, few investigations have attempted to discern commonalities among individual responses to neuromodulation, especially the impact of stimulation frequencies. Here, we examined how exposure to continuous lumbosacral transcutaneous spinal stimulation (TSS) across a range of frequencies affects robotic torques and EMG patterns during stepping in a robotic gait orthosis on a motorized treadmill. We studied nine chronic motor-incomplete SCI individuals (8/1 AIS-C/D, 8 men) during robot-guided stepping with body-weight support without and with TSS applied at random frequencies between 1 and up to 100 Hz at a constant, individually selected stimulation intensity below the common motor threshold for posterior root reflexes. The hip and knee robotic torques needed to maintain the predefined stepping trajectory and EMG in eight bilateral leg muscles were recorded. We calculated the standardized mean difference between the stimulation conditions grouped into frequency bins and the no stimulation condition to determine changes in the normalized torques and the average EMG envelopes. We found heterogeneous changes in robotic torques across individuals. Agglomerative clustering of robotic torques identified four groups wherein the patterns of changes differed in magnitude and direction depending mainly on the stimulation frequency and stance/swing phase. On one end of the spectrum, the changes in robotic torques were greater with increasing stimulation frequencies (four participants), which coincided with a decrease in EMG, mainly due to the reduction of clonogenic motor output in the lower leg muscles. On the other end, we found an inverted u-shape change in torque over the mid-frequency range along with an increase in EMG, reflecting the augmentation of gait-related physiological (two participants) or pathophysiological (one participant) output. We conclude that TSS during robot-guided stepping reveals different frequency-dependent motor profiles among individuals with chronic motor incomplete SCI. This suggests the need for a better understanding and characterization of motor control profiles in SCI when applying TSS as a therapeutic intervention for improving gait.
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Skiadopoulos A, Pulverenti TS, Knikou M. Physiological effects of cathodal electrode configuration for transspinal stimulation in humans. J Neurophysiol 2022; 128:1663-1682. [PMID: 36416443 PMCID: PMC9762966 DOI: 10.1152/jn.00342.2022] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Revised: 11/16/2022] [Accepted: 11/17/2022] [Indexed: 11/24/2022] Open
Abstract
Transspinal stimulation modulates neuronal excitability and promotes recovery in upper motoneuron lesions. The recruitment input-output curves of transspinal evoked potentials (TEPs) recorded from knee and ankle muscles, and their susceptibility to spinal inhibition, were recorded when the position, size, and number of the cathode electrode were arranged in four settings or protocols (Ps). The four Ps were the following: 1) one rectangular electrode placed at midline (KNIKOU-LAB4Recovery or K-LAB4Recovery; P-KLAB), 2) one square electrode placed at midline (P-2), 3) two square electrodes 1 cm apart placed at midline (P-3), and 4) one square electrode placed on each paravertebral side (P-4). P-KLAB and P-3 required less current to reach TEP threshold or maximal amplitudes. A rightward shift in TEP recruitment curves was evident for P-4, whereas the slope was increased for P-2 and P-4 compared with P-KLAB and P-3. TEP depression upon single and paired transspinal stimuli was pronounced in ankle TEPs but was less prominent in knee TEPs. TEP depression induced by single transspinal stimuli at 1.0 Hz was similar for most TEPs across protocols, but TEP depression induced by paired transspinal stimuli was different between protocols and was replaced by facilitation at 100-ms interstimulus interval for P-4. Our results suggest that P-KLAB and P-3 are preferred based on excitability threshold of motoneurons. P-KLAB produced more TEP depression, thereby maximizing the engagement of spinal neuronal pathways. We recommend P-KLAB to study neurophysiological mechanisms underlying transspinal stimulation or when used as a neuromodulation method for recovery in neurological disorders.NEW & NOTEWORTHY Transspinal stimulation with a rectangular cathode electrode (P-KLAB) requires less current to produce transspinal evoked potentials and maximizes spinal inhibition. We recommend P-KLAB for neurophysiological studies or when used as a neuromodulation method to enhance motor output and normalize muscle tone in neurological disorders.
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Affiliation(s)
- Andreas Skiadopoulos
- Klab4Recovery Research Program, The City University of New York, New York, New York
| | - Timothy S Pulverenti
- Klab4Recovery Research Program, The City University of New York, New York, New York
| | - Maria Knikou
- Klab4Recovery Research Program, The City University of New York, New York, New York
- Department of Physical Therapy, College of Staten Island, The City University of New York, Staten Island, New York
- PhD Program in Biology and Collaborative Neuroscience Program, Graduate Center of The City University of New York and College of Staten Island, Staten Island, New York
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12
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Pulverenti TS, Zaaya M, Grabowski E, Grabowski M, Knikou M. Brain and spinal cord paired stimulation coupled with locomotor training facilitates motor output in human spinal cord injury. Front Neurol 2022; 13:1000940. [PMID: 36313489 PMCID: PMC9612520 DOI: 10.3389/fneur.2022.1000940] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 09/26/2022] [Indexed: 11/21/2022] Open
Abstract
Combined interventions for neuromodulation leading to neurorecovery have gained great attention by researchers to resemble clinical rehabilitation approaches. In this randomized clinical trial, we established changes in the net output of motoneurons innervating multiple leg muscles during stepping when transcranial magnetic stimulation (TMS) of the primary motor cortex was paired with transcutaneous spinal (transspinal) stimulation over the thoracolumbar region during locomotor training. TMS was delivered before (TMS-transspinal) or after (transspinal-TMS) transspinal stimulation during the stance phase of the less impaired leg. Ten individuals with chronic incomplete or complete SCI received at least 20 sessions of training. Each session consisted of 240 paired stimuli delivered over 10-min blocks for 1 h during robotic assisted step training on a motorized treadmill. Body weight support, leg guidance force and treadmill speed were adjusted based on each subject's ability to step without knee buckling or toe dragging. Most transspinal evoked potentials (TEPs) recorded before and after each intervention from ankle and knee muscles during assisted stepping were modulated in a phase-dependent pattern. Transspinal-TMS and locomotor training affected motor neuron output of knee and ankle muscles with ankle TEPs to be modulated in a phase-dependent manner. TMS-transspinal and locomotor training increased motor neuron output for knee but not for ankle muscles. Our results support that targeted brain and spinal cord stimulation alters responsiveness of neurons over multiple spinal segments in people with chronic SCI. Noninvasive stimulation of the brain and spinal cord along with locomotor training is a novel neuromodulation method that can become a promising modality for rehabilitation in humans after SCI.
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Affiliation(s)
- Timothy S. Pulverenti
- Klab4Recovery Research Program, The City University of New York, New York, NY, United States
| | - Morad Zaaya
- Klab4Recovery Research Program, The City University of New York, New York, NY, United States
| | - Ewelina Grabowski
- PhD Program in Biology and Collaborative Neuroscience Program, Graduate Center of the City University of New York and College of Staten Island, New York, NY, United States
| | - Monika Grabowski
- PhD Program in Biology and Collaborative Neuroscience Program, Graduate Center of the City University of New York and College of Staten Island, New York, NY, United States
| | - Maria Knikou
- Klab4Recovery Research Program, The City University of New York, New York, NY, United States,PhD Program in Biology and Collaborative Neuroscience Program, Graduate Center of the City University of New York and College of Staten Island, New York, NY, United States,Department of Physical Therapy, College of Staten Island, The City University of New York, New York, NY, United States,*Correspondence: Maria Knikou
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Huang CX, Wang Z, Cheng J, Zhu Z, Guan NN, Song J. De novo establishment of circuit modules restores locomotion after spinal cord injury in adult zebrafish. Cell Rep 2022; 41:111535. [DOI: 10.1016/j.celrep.2022.111535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 08/12/2022] [Accepted: 09/29/2022] [Indexed: 11/03/2022] Open
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Brain and spinal cord paired stimulation coupled with locomotor training affects polysynaptic flexion reflex circuits in human spinal cord injury. Exp Brain Res 2022; 240:1687-1699. [PMID: 35513720 DOI: 10.1007/s00221-022-06375-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 04/15/2022] [Indexed: 12/19/2022]
Abstract
Neurorecovery from locomotor training is well established in human spinal cord injury (SCI). However, neurorecovery resulting from combined interventions has not been widely studied. In this randomized clinical trial, we established the tibialis anterior (TA) flexion reflex modulation pattern when transcranial magnetic stimulation (TMS) of the primary motor cortex was paired with transcutaneous spinal cord (transspinal) stimulation over the thoracolumbar region during assisted step training. Single pulses of TMS were delivered either before (TMS-transspinal) or after (transspinal-TMS) transspinal stimulation during the stance phase of the less impaired leg. Eight individuals with chronic incomplete or complete SCI received at least 20 sessions of paired stimulation during assisted step training. Each session consisted of 240 paired stimuli delivered over 10-min blocks for 1 h during robotic-assisted step training with the Lokomat6 Pro®. Body weight support, leg guidance force and treadmill speed were adjusted based on each participant's ability to step without knee buckling or toe dragging. Both the early and late TA flexion reflex remained unaltered after TMS-transspinal and locomotor training. In contrast, the early and late TA flexion reflexes were significantly depressed during stepping after transspinal-TMS and locomotor training. Reflex changes occurred at similar slopes and intercepts before and after training. Our findings support that targeted brain and spinal cord stimulation coupled with locomotor training reorganizes the function of flexion reflex pathways, which are a part of locomotor networks, in humans with varying levels of sensorimotor function after SCI.Trial registration number NCT04624607; Registered on November 12, 2020.
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15
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Martinez M. Targeting the motor cortex to restore walking after incomplete spinal cord injury. Neural Regen Res 2021; 17:1489-1490. [PMID: 34916428 PMCID: PMC8771094 DOI: 10.4103/1673-5374.330603] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- Marina Martinez
- Département de Neurosciences, Groupe de recherche sur la Signalisation Neurale et la Circuiterie and Centre Interdisciplinaire de Recherche sur le Cerveau au service de l'Apprentissage, Université de Montréal; CIUSSS du Nord-de-l'Île-de-Montréal, Montréal, QC, Canada
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16
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Noga BR, Guest JD. Combined neuromodulatory approaches in the central nervous system for treatment of spinal cord injury. Curr Opin Neurol 2021; 34:804-811. [PMID: 34593718 PMCID: PMC8595808 DOI: 10.1097/wco.0000000000000999] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
PURPOSE OF REVIEW To report progress in neuromodulation following spinal cord injury (SCI) using combined brain and spinal neuromodulation.Neuromodulation refers to alterations in neuronal activity for therapeutic purposes. Beneficial effects are established in disease states such as Parkinson's Disease (PD), chronic pain, epilepsy, and SCI. The repertoire of neuromodulation and bioelectric medicine is rapidly expanding. After SCI, cohort studies have reported the benefits of epidural stimulation (ES) combined with training. Recently, we have explored combining ES with deep brain stimulation (DBS) to increase activation of descending motor systems to address limitations of ES in severe SCI. In this review, we describe the types of applied neuromodulation that could be combined in SCI to amplify efficacy to enable movement. These include ES, mesencephalic locomotor region (MLR) - DBS, noninvasive transcutaneous stimulation, transcranial magnetic stimulation, paired-pulse paradigms, and neuromodulatory drugs. We examine immediate and longer-term effects and what is known about: (1) induced neuroplastic changes, (2) potential safety concerns; (3) relevant outcome measures; (4) optimization of stimulation; (5) therapeutic limitations and prospects to overcome these. RECENT FINDINGS DBS of the mesencephalic locomotor region is emerging as a potential clinical target to amplify supraspinal command circuits for locomotion. SUMMARY Combinations of neuromodulatory methods may have additive value for restoration of function after spinal cord injury.
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Affiliation(s)
- Brian R Noga
- The Miami Project to Cure Paralysis, Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami, Florida, USA
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Kaneko N, Sasaki A, Masugi Y, Nakazawa K. The Effects of Paired Associative Stimulation with Transcutaneous Spinal Cord Stimulation on Corticospinal Excitability in Multiple Lower-limb Muscles. Neuroscience 2021; 476:45-59. [PMID: 34500017 DOI: 10.1016/j.neuroscience.2021.08.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 08/25/2021] [Accepted: 08/26/2021] [Indexed: 11/29/2022]
Abstract
Paired associative stimulation (PAS) is a non-invasive method to modulate the excitability of the primary motor cortex (M1). PAS involves the combination of peripheral nerve stimulation and transcranial magnetic stimulation (TMS) over the primary motor cortex. However, for lower-limb muscles, PAS has only been applied to the few muscles innervated by peripheral nerves that can easily be stimulated. This study used transcutaneous spinal cord stimulation (tSCS) to the posterior root, stimulating the sensory nerves of multiple lower-limb muscles, and aimed to investigate the effect of PAS consisting of tSCS and TMS on corticospinal excitability. Twelve non-disabled men received 120 paired stimuli on two separate days in (1) an individual-ISI condition, using inter-stimulus intervals (ISIs) of paired stimuli individually calculated to send two signals to M1 with individually-adjusted ISI, and (2) a constant-ISI condition, using a constant ISI of 100 ms. Before and after PAS, corticospinal excitability was assessed in the lower-limb muscles. Facilitation of corticospinal excitability in the lower-leg and hamstring muscles was observed up to 30 min after PAS only in the individual-ISI condition (p < 0.05), although there was no significant difference between the individual-ISI and constant-ISI conditions. Additionally, our results revealed a difference in PAS-induced facilitation among lower-limb muscles, suggesting a spatial gradient of PAS-induced facilitation of corticospinal excitability, such that knee flexor muscles have a higher potential for plastic change than knee extensor muscles. These findings will foster a better understanding of the neural mechanisms underlying PAS-induced neuroplasticity, leading to better neurorehabilitation and motor learning strategies.
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Affiliation(s)
- Naotsugu Kaneko
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan; Japan Society for the Promotion of Science, Tokyo, Japan; Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada; KITE, Toronto Rehabilitation Institute - University Health Network, Toronto, ON, Canada
| | - Atsushi Sasaki
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan; Japan Society for the Promotion of Science, Tokyo, Japan
| | - Yohei Masugi
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan; School of Health Sciences, Tokyo International University, Saitama, Japan
| | - Kimitaka Nakazawa
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan.
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18
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Al'joboori Y, Hannah R, Lenham F, Borgas P, Kremers CJP, Bunday KL, Rothwell J, Duffell LD. The Immediate and Short-Term Effects of Transcutaneous Spinal Cord Stimulation and Peripheral Nerve Stimulation on Corticospinal Excitability. Front Neurosci 2021; 15:749042. [PMID: 34744614 PMCID: PMC8566815 DOI: 10.3389/fnins.2021.749042] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 09/27/2021] [Indexed: 12/17/2022] Open
Abstract
Rehabilitative interventions involving electrical stimulation show promise for neuroplastic recovery in people living with Spinal Cord Injury (SCI). However, the understanding of how stimulation interacts with descending and spinal excitability remain unclear. In this study we compared the immediate and short-term (within a few minutes) effects of pairing Transcranial Magnetic Stimulation (TMS) with transcutaneous Spinal Cord stimulation (tSCS) and Peripheral Nerve Stimulation (PNS) on Corticospinal excitability in healthy subjects. Three separate experimental conditions were assessed. In Experiment I, paired associative stimulation (PAS) was applied, involving repeated pairing of single pulses of TMS and tSCS, either arriving simultaneously at the spinal motoneurones (PAS0ms) or slightly delayed (PAS5ms). Corticospinal and spinal excitability, and motor performance, were assessed before and after the PAS interventions in 24 subjects. Experiment II compared the immediate effects of tSCS and PNS on corticospinal excitability in 20 subjects. Experiment III compared the immediate effects of tSCS with tSCS delivered at the same stimulation amplitude but modulated with a carrier frequency (in the kHz range) on corticospinal excitability in 10 subjects. Electromyography (EMG) electrodes were placed over the Tibialis Anterior (TA) soleus (SOL) and vastus medialis (VM) muscles and stimulation electrodes (cathodes) were placed on the lumbar spine (tSCS) and lateral to the popliteal fossa (PNS). TMS over the primary motor cortex (M1) was paired with tSCS or PNS to produce Motor Evoked Potentials (MEPs) in the TA and SOL muscles. Simultaneous delivery of repetitive PAS (PAS0ms) increased corticospinal excitability and H-reflex amplitude at least 5 min after the intervention, and dorsiflexion force was increased in a force-matching task. When comparing effects on descending excitability between tSCS and PNS, a subsequent facilitation in MEPs was observed following tSCS at 30-50 ms which was not present following PNS. To a lesser extent this facilitatory effect was also observed with HF- tSCS at subthreshold currents. Here we have shown that repeated pairing of TMS and tSCS can increase corticospinal excitability when timed to arrive simultaneously at the alpha-motoneurone and can influence functional motor output. These results may be useful in optimizing stimulation parameters for neuroplasticity in people living with SCI.
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Affiliation(s)
- Yazi Al'joboori
- Department of Medical Physics & Biomedical Engineering, University College London, London, United Kingdom
| | - Ricci Hannah
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, London, United Kingdom
| | - Francesca Lenham
- Department of Medical Physics & Biomedical Engineering, University College London, London, United Kingdom
| | - Pia Borgas
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, London, United Kingdom
| | - Charlotte J P Kremers
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, London, United Kingdom
| | - Karen L Bunday
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, London, United Kingdom.,Psychology, School of Social Sciences, University of Westminster, London, United Kingdom
| | - John Rothwell
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, London, United Kingdom
| | - Lynsey D Duffell
- Department of Medical Physics & Biomedical Engineering, University College London, London, United Kingdom
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