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Granata G, Di Iorio R, Ilari S, Angeloni BM, Tomasello F, Cimmino AT, Carrarini C, Marrone A, Iodice F. Phantom limb syndrome: from pathogenesis to treatment. A narrative review. Neurol Sci 2024; 45:4741-4755. [PMID: 38853232 DOI: 10.1007/s10072-024-07634-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Accepted: 06/04/2024] [Indexed: 06/11/2024]
Abstract
Phantom Limb Syndrome (PLS) can be defined as the disabling or painful sensation of the presence of a body part that is no longer present after its amputation. Anatomical changes involved in Phantom Limb Syndrome, occurring at peripheral, spinal and brain levels and include the formation of neuromas and scars, dorsal horn sensitization and plasticity, short-term and long-term modifications at molecular and topographical levels. The molecular reorganization processes of Phantom Limb Syndrome include NMDA receptors hyperactivation in the dorsal horn of the spinal column leading to inflammatory mechanisms both at a peripheral and central level. At the brain level, a central role has been recognized for sodium channels, BDNF and adenosine triphosphate receptors. In the paper we discuss current available pharmacological options with a final overview on non-pharmacological options in the pipeline.
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Affiliation(s)
- Giuseppe Granata
- Institute of Neurology, Fondazione Policlinico Gemelli IRCCS, Rome, Italy
| | - Riccardo Di Iorio
- Institute of Neurology, Fondazione Policlinico Gemelli IRCCS, Rome, Italy
| | - Sara Ilari
- Laboratory of Physiology and Pharmacology of Pain, IRCCS San Raffaele, Rome, Italy
| | | | - Fabiola Tomasello
- Department of Neuroscience, Catholic University of the Sacred Heart, Rome, Italy
| | | | - Claudia Carrarini
- Department of Neuroscience, Catholic University of the Sacred Heart, Rome, Italy
- Institute of Neurology and Neurorehabilitation, IRCCS San Raffaele, Via Della Pisana 235, 00160, Rome, Italy
| | - Antonio Marrone
- Institute of Neurology and Neurorehabilitation, IRCCS San Raffaele, Via Della Pisana 235, 00160, Rome, Italy
| | - Francesco Iodice
- Institute of Neurology and Neurorehabilitation, IRCCS San Raffaele, Via Della Pisana 235, 00160, Rome, Italy.
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Chung SM, Wang JC, Lin CR, Liu SC, Wu PT, Kuan FC, Fang CJ, Tu YK, Hsu KL, Lai PC, Shih CA. Beyond traditional therapies: a network meta-analysis on the treatment efficacy for chronic phantom limb pain. Reg Anesth Pain Med 2024:rapm-2023-105104. [PMID: 38388020 DOI: 10.1136/rapm-2023-105104] [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: 10/19/2023] [Accepted: 01/24/2024] [Indexed: 02/24/2024]
Abstract
BACKGROUND Phantom limb pain (PLP) frequently affects individuals with limb amputations. When PLP evolves into its chronic phase, known as chronic PLP, traditional therapies often fall short in providing sufficient relief. The optimal intervention for chronic PLP remains unclear. OBJECTIVE The objectives of this network meta-analysis (NMA) were to examine the efficacy of different treatments on pain intensity for patients with chronic PLP. EVIDENCE REVIEW We searched Medline, EMBASE, Cochrane CENTRAL, Scopus, and CINAHL EBSCO, focusing on randomized controlled trials (RCTs) that evaluated interventions such as neuromodulation, neural block, pharmacological methods, and alternative treatments. An NMA was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The primary outcome was pain score improvement, and the secondary outcomes were adverse events. FINDINGS The NMA, incorporating 12 RCTs, indicated that neuromodulation, specifically repetitive transcranial magnetic stimulation, provided the most substantial pain improvement when compared with placebo/sham groups (mean difference=-2.9 points, 95% CI=-4.62 to -1.18; quality of evidence (QoE): moderate). Pharmacological intervention using morphine was associated with a significant increase in adverse event rate (OR=6.04, 95% CI=2.26 to 16.12; QoE: low). CONCLUSIONS The NMA suggests that neuromodulation using repetitive transcranial magnetic stimulation may be associated with significantly larger pain improvement for chronic PLP. However, the paucity of studies, varying patient characteristics across each trial, and absence of long-term results underscore the necessity for more comprehensive, large-scale RCTs. PROSPERO REGISTRATION NUMBER CRD42023455949.
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Affiliation(s)
- Sun-Mei Chung
- Mackay Memorial Hospital, Taipei, Taiwan
- School of Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Jui-Chien Wang
- School of Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Taipei Veterans General Hospital, Taipei, Taiwan
| | - Chung-Ren Lin
- Department of Anesthesiology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Shu-Cheng Liu
- Department of Anesthesiology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Po-Ting Wu
- Department of Orthopedics, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Department of Orthopedics, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Fa-Chuan Kuan
- Department of Orthopedics, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Medical Device R & D Core Laboratory, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Ching-Ju Fang
- Department of Secretariat, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Medical Library, National Cheng Kung University, Tainan, Taiwan
| | - Yu-Kang Tu
- Institute of Epidemiology and Preventive Medicine, National Taiwan University College of Public Health, Taipei, Taiwan
- Department of Dentistry, National Taiwan University Hospital, Taipei, Taiwan
| | - Kai-Lan Hsu
- Department of Orthopedics, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Medical Device R & D Core Laboratory, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Pei-Chun Lai
- Education Center, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chien-An Shih
- Department of Orthopedics, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Department of Orthopedics, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Medical Device R & D Core Laboratory, National Cheng Kung University Hospital, Tainan, Taiwan
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Markewych AN, Suvar T, Swanson MA, Graca MJ, Lubenow TR, McCarthy RJ, Buvanendran A, Kurlander DE. Approaches to neuropathic amputation-related pain: narrative review of surgical, interventional, and medical treatments. Reg Anesth Pain Med 2024:rapm-2023-105089. [PMID: 38307612 DOI: 10.1136/rapm-2023-105089] [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: 10/12/2023] [Accepted: 12/26/2023] [Indexed: 02/04/2024]
Abstract
BACKGROUND/IMPORTANCE Neuropathic amputation-related pain can consist of phantom limb pain (PLP), residual limb pain (RLP), or a combination of both pathologies. Estimated of lifetime prevalence of pain and after amputation ranges between 8% and 72%. OBJECTIVE This narrative review aims to summarize the surgical and non-surgical treatment options for amputation-related neuropathic pain to aid in developing optimized multidisciplinary and multimodal treatment plans that leverage multidisciplinary care. EVIDENCE REVIEW A search of the English literature using the following keywords was performed: PLP, amputation pain, RLP. Abstract and full-text articles were evaluated for surgical treatments, medical management, regional anesthesia, peripheral block, neuromodulation, spinal cord stimulation, dorsal root ganglia, and peripheral nerve stimulation. FINDINGS The evidence supporting most if not all interventions for PLP are inconclusive and lack high certainty. Targeted muscle reinnervation and regional peripheral nerve interface are the leading surgical treatment options for reducing neuroma formation and reducing PLP. Non-surgical options include pharmaceutical therapy, regional interventional techniques and behavioral therapies that can benefit certain patients. There is a growing evidence that neuromodulation at the spinal cord or the dorsal root ganglia and/or peripheral nerves can be an adjuvant therapy for PLP. CONCLUSIONS Multimodal approaches combining pharmacotherapy, surgery and invasive neuromodulation procedures would appear to be the most promising strategy for preventive and treating PLP and RLP. Future efforts should focus on cross-disciplinary education to increase awareness of treatment options exploring best practices for preventing pain at the time of amputation and enhancing treatment of chronic postamputation pain.
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Affiliation(s)
| | - Tolga Suvar
- Department of Anesthesiology, Rush University Medical Center, Chicago, Illinois, USA
| | - Marco A Swanson
- Department of Plastic & Reconstructive Surgery, Cleveland Clinic Foundation, Cleveland, Ohio, USA
| | - Mateusz J Graca
- Department of Anesthesiology, Rush University Medical Center, Chicago, Illinois, USA
| | - Timothy R Lubenow
- Department of Anesthesiology, Rush University Medical Center, Chicago, Illinois, USA
| | - Robert J McCarthy
- Department of Anesthesiology, Rush University Medical Center, Chicago, Illinois, USA
| | - Asokumar Buvanendran
- Department of Anesthesiology, Rush University Medical Center, Chicago, Illinois, USA
| | - David E Kurlander
- Department of Plastic & Reconstructive Surgery, Rush University Medical Center, Chicago, Illinois, USA
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Sparling T, Iyer L, Pasquina P, Petrus E. Cortical Reorganization after Limb Loss: Bridging the Gap between Basic Science and Clinical Recovery. J Neurosci 2024; 44:e1051232024. [PMID: 38171645 PMCID: PMC10851691 DOI: 10.1523/jneurosci.1051-23.2023] [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: 06/08/2023] [Revised: 08/28/2023] [Accepted: 09/29/2023] [Indexed: 01/05/2024] Open
Abstract
Despite the increasing incidence and prevalence of amputation across the globe, individuals with acquired limb loss continue to struggle with functional recovery and chronic pain. A more complete understanding of the motor and sensory remodeling of the peripheral and central nervous system that occurs postamputation may help advance clinical interventions to improve the quality of life for individuals with acquired limb loss. The purpose of this article is to first provide background clinical context on individuals with acquired limb loss and then to provide a comprehensive review of the known motor and sensory neural adaptations from both animal models and human clinical trials. Finally, the article bridges the gap between basic science researchers and clinicians that treat individuals with limb loss by explaining how current clinical treatments may restore function and modulate phantom limb pain using the underlying neural adaptations described above. This review should encourage the further development of novel treatments with known neurological targets to improve the recovery of individuals postamputation.Significance Statement In the United States, 1.6 million people live with limb loss; this number is expected to more than double by 2050. Improved surgical procedures enhance recovery, and new prosthetics and neural interfaces can replace missing limbs with those that communicate bidirectionally with the brain. These advances have been fairly successful, but still most patients experience persistent problems like phantom limb pain, and others discontinue prostheses instead of learning to use them daily. These problematic patient outcomes may be due in part to the lack of consensus among basic and clinical researchers regarding the plasticity mechanisms that occur in the brain after amputation injuries. Here we review results from clinical and animal model studies to bridge this clinical-basic science gap.
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Affiliation(s)
- Tawnee Sparling
- Department of Physical Medicine and Rehabilitation, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814
| | - Laxmi Iyer
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, Maryland 20817
| | - Paul Pasquina
- Department of Physical Medicine and Rehabilitation, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814
| | - Emily Petrus
- Department of Anatomy, Physiology and Genetics, Uniformed Services University, Bethesda, Maryland 20814
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Norton KF, Furnish TJ. Perspectives on the pharmacological management of complex regional pain syndrome. Expert Opin Pharmacother 2023; 24:1295-1305. [PMID: 37224182 DOI: 10.1080/14656566.2023.2218032] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 05/22/2023] [Indexed: 05/26/2023]
Abstract
INTRODUCTION Complex regional pain syndrome (CRPS) is a chronic pain condition that is notoriously difficult to treat. Therapies for CRPS include cognitive behavioral, physical, and occupational therapy, single or multidrug pharmacotherapy, and a variety of interventional techniques. Unfortunately, randomized clinical trials of these therapies are limited. The large number of potential pharmacologic options can be overwhelming for providers in their attempts to develop a treatment plan. AREAS COVERED This article will review the literature on the pharmacologic management of CRPS. It is based on a systematic search of PubMed using keywords, followed by evaluation of the bibliographies for relevant articles. EXPERT OPINION No single drug has amassed enough evidence to suggest clear efficacy, but a handful of agents with at least modest evidence are commonly used, including gabapentinoids, bisphosphonates, ketamine, and pulsed dose steroids. Meanwhile, other agents that lack significant evidence specifically in CRPS but have evidence in other neuropathic conditions are commonly prescribed, including tricyclic antidepressants (TCAs) and selective serotonin reuptake inhibitors (SNRIs). In our opinion, careful selection and prompt initiation of appropriate pharmacotherapy may optimize pain relief and improve functionality in patients burdened with this debilitating condition.
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Affiliation(s)
- Kyle F Norton
- Department of Anesthesiology, UC San Diego Medical Center, San Diego, CA, USA
| | - Timothy J Furnish
- Department of Anesthesiology, UC San Diego Medical Center, San Diego, CA, USA
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Wang J, Fan J, Gc R, Zhao J. Comparative Effects of Interventions on Phantom Limb Pain: A Network Meta-Analysis. World Neurosurg 2023; 170:e45-e56. [PMID: 36273725 DOI: 10.1016/j.wneu.2022.10.060] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 10/17/2022] [Indexed: 11/07/2022]
Abstract
BACKGROUND Phantom limb pain (PLP) is a common type of chronic pain that occurs after limb amputation. Many treatment approaches are available; however, the treatment of PLP is still a challenge. This study aimed to quantify and rank the efficacy of interventions for phantom limb pain. METHODS A comprehensive literature search was performed using the databases of PubMed, MEDLINE, Embase, Web of Science, and Cochrane. A network meta-analysis was applied to formulate direct and indirect comparisons among interventions for PLP. RESULTS Twenty-two studies comprising 662 patients and 13 different interventions were included in this study. The mirror therapy (MT) (-1.00; 95% confidence interval, -1.94 to -0.07) and MT + phantom exercise (PE) (-6.05; 95% confidence interval, -8.29 to -3.81) group presented significantly lower pain intensity compared with placebo. In SUCRA (surface under the cumulative ranking curve) analysis, the MT+PE and neuromodulation techniques groups had the highest SUCRA value (81.2). CONCLUSIONS Our results suggest that MT is the most optimal treatment for PLP, and a combination of therapies would enhance the therapeutic effect.
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Affiliation(s)
- Jingwei Wang
- Department of Orthopedics, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Jingyuan Fan
- Department of Orthopedics, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Raju Gc
- Department of Orthopedics, Mercy City Hospital, Butwol, Nepal
| | - Jinmin Zhao
- Department of Orthopedics, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China.
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7
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Klinisches Update zu Phantomschmerz. Schmerz 2022; 37:195-214. [DOI: 10.1007/s00482-022-00629-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/02/2022] [Indexed: 10/18/2022]
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Israel JE, St Pierre S, Ellis E, Hanukaai JS, Noor N, Varrassi G, Wells M, Kaye AD. Ketamine for the Treatment of Chronic Pain: A Comprehensive Review. Health Psychol Res 2021; 9:25535. [PMID: 34746491 DOI: 10.52965/001c.25535] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 07/06/2021] [Indexed: 12/14/2022] Open
Abstract
Background Chronic pain significantly worsens the quality of life. Unlike neuropathic, musculoskeletal, postoperative pain, and cancer pain, chronic primary pain cannot be explained by an underlying disease or condition, making its treatment arduous. Objectives This manuscript intends to provide a comprehensive review of the use of ketamine as a treatment option for specific chronic pain conditions. Study Design A review article. Setting A review of the literature. Methods A search was done on PubMed for relevant articles. Results A comprehensive review of the current understanding of chronic pain and the treatment of specific chronic pain conditions with ketamine. Limitations Literature is scarce regarding the use of ketamine for the treatment of chronic pain. Conclusion First-line treatment for many chronic pain conditions includes NSAIDs, antidepressants, anticonvulsants, and opioids. However, these treatment methods are unsuccessful in a subset of patients. Ketamine has been explored in randomized controlled trials (RCTs) as an alternative treatment option, and it has been demonstrated to improve pain symptoms, patient satisfaction, and quality of life. Conditions highlighted in this review include neuropathic pain, fibromyalgia, complex regional pain syndrome (CRPS), phantom limb pain (PLP), cancer pain, and post-thoracotomy pain syndrome. This review will discuss conditions, such as neuropathic pain, fibromyalgia, complex regional pain syndrome, and more and ketamine's efficacy and its supplementary benefits in the chronic pain patient population. As the opioid crisis in the United States continues to persist, this review aims to understand better multimodal analgesia, which can improve how chronic pain is managed.
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Affiliation(s)
| | | | - Emily Ellis
- Louisiana State University Health Shreveport
| | | | | | | | | | - Alan D Kaye
- Louisiana State University Health Shreveport
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Abstract
Symptomatic neuromas and chronic neuropathic pain are significant problems affecting patients' quality of life and independence that are challenging to treat. These symptoms are due to structural and functional changes that occur peripherally within neuromas, as well as alterations that occur centrally within the brain and spinal cord. A multimodal approach is most effective, with goals to minimize opioid use, to capitalize on the synergistic effects of nonopioid medications and to explore potential benefits of novel adjunctive treatments.
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Affiliation(s)
- Yusha Liu
- Department of Surgery, University of Washington, 325 9th Avenue, 7 CT 70, MS 359796, Seattle, WA 98104, USA
| | - Dennis S Kao
- Department of Surgery, University of Washington, 325 9th Avenue, 7 CT 70, MS 359796, Seattle, WA 98104, USA.
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Abstract
Phantom limb pain is highly prevalent after amputation. Treatment results will probably benefit from an interdisciplinary team and individually adapted surgical, prosthetic and pain medicine approaches. Introduction: Most patients with amputation (up to 80%) suffer from phantom limb pain postsurgery. These are often multimorbid patients who also have multiple risk factors for the development of chronic pain from a pain medicine perspective. Surgical removal of the body part and sectioning of peripheral nerves result in a lack of afferent feedback, followed by neuroplastic changes in the sensorimotor cortex. The experience of severe pain, peripheral, spinal, and cortical sensitization mechanisms, and changes in the body scheme contribute to chronic phantom limb pain. Psychosocial factors may also affect the course and the severity of the pain. Modern amputation medicine is an interdisciplinary responsibility. Methods: This review aims to provide an interdisciplinary overview of recent evidence-based and clinical knowledge. Results: The scientific evidence for best practice is weak and contrasted by various clinical reports describing the polypragmatic use of drugs and interventional techniques. Approaches to restore the body scheme and integration of sensorimotor input are of importance. Modern techniques, including apps and virtual reality, offer an exciting supplement to already established approaches based on mirror therapy. Targeted prosthesis care helps to obtain or restore limb function and at the same time plays an important role reshaping the body scheme. Discussion: Consequent prevention and treatment of severe postoperative pain and early integration of pharmacological and nonpharmacological interventions are required to reduce severe phantom limb pain. To obtain or restore body function, foresighted surgical planning and technique as well as an appropriate interdisciplinary management is needed.
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DI Pino G, Piombino V, Carassiti M, Ortiz-Catalan M. Neurophysiological models of phantom limb pain: what can be learnt. Minerva Anestesiol 2021; 87:481-487. [PMID: 33432796 DOI: 10.23736/s0375-9393.20.15067-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Phantom Limb Pain (PLP) is a dysesthesic painful sensations perceived in the lost limb, resulting from complex interactions between structural and functional nervous systems changes. We analyze its main pathogenetic models and speculate on candidate therapeutic targets. The neuroma model considers PLP to arise from spontaneous activity of residual limb injured axons. Other peripheral-origin models attribute PLP to damage of somatosensory receptors or vascular changes. According to the cortical remapping model, the loss of bidirectional nervous flow and the need to enhance alternative functions trigger reorganization and arm and face skin afferents "invade" the hand territory. On the contrary, the persistent representation model suggests that continued inputs preserve the lost limb representation and that, instead to a shrinkage, PLP is associated with larger representation and stronger cortical activity. In the neuromatrix model, the mismatch between body representation, which remains intact despite limb amputation, and real body appearance generates pain. Another hypothesis is that proprioceptive memories associate specific limb positions with pre-amputation pain and may be recalled by those positions. Finally, the stochastic entanglement model offers a direct relationship between sensorimotor neural reorganization and pain. Amputation disrupts motor and somatosensory circuits, allowing for maladaptive wiring with pain circuits and causing pain without nociception. Relief of PLP depends solely on motor and somatosensory circuitry engagement, making anthropomorphic visual feedback dispensable. Existing and apparently contradicting theories might not be mutually exclusive. All of them involve several intertwined potential mechanisms by which replacing the amputated limb by an artificial one could counteract PLP.
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Affiliation(s)
- Giovanni DI Pino
- Research Unit of Neurophysiology and Neuroengineering of Human-Technology Interaction (NeXTlab), Campus Bio-Medico University, Rome, Italy -
| | - Valeria Piombino
- Research Unit of Neurophysiology and Neuroengineering of Human-Technology Interaction (NeXTlab), Campus Bio-Medico University, Rome, Italy
| | - Massimiliano Carassiti
- Unit of Anesthesia, Intensive Care and Pain Management, Department of Medicine, Campus Bio-Medico University, Rome, Italy
| | - Max Ortiz-Catalan
- Center for Bionics and Pain Research, Mölndal, Sweden.,Department of Electrical Engineering, Chalmers University of Technology, Gothenburg, Sweden.,Operational Area 3, Sahlgrenska University Hospital, Mölndal, Sweden.,Department of Orthopedics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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12
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Pacheco-Barrios K, Pinto CB, Saleh Velez FG, Duarte D, Gunduz ME, Simis M, Lepesteur Gianlorenco AC, Barouh JL, Crandell D, Guidetti M, Battistella L, Fregni F. Structural and functional motor cortex asymmetry in unilateral lower limb amputation with phantom limb pain. Clin Neurophysiol 2020; 131:2375-2382. [PMID: 32828040 DOI: 10.1016/j.clinph.2020.06.024] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 04/27/2020] [Accepted: 06/01/2020] [Indexed: 10/23/2022]
Abstract
OBJECTIVE The role of motor cortex reorganization in the development and maintenance of phantom limb pain (PLP) is still unclear. This study aims to evaluate neurophysiological and structural motor cortex asymmetry in patients with PLP and its relationship with pain intensity. METHODS Cross-sectional analysis of an ongoing randomized-controlled trial. We evaluated the motor cortex asymmetry through two techniques: i) changes in cortical excitability indexed by transcranial magnetic stimulation (motor evoked potential, paired-pulse paradigms and cortical mapping), and ii) voxel-wise grey matter asymmetry analysis by brain magnetic resonance imaging. RESULTS We included 62 unilateral traumatic lower limb amputees with a mean PLP of 5.9 (SD = 1.79). We found, in the affected hemisphere, an anterior shift of the hand area center of gravity (23 mm, 95% CI 6 to 38, p = 0.005) and a disorganized and widespread representation. Regarding voxel-wise grey matter asymmetry analysis, data from 21 participants show a loss of grey matter volume in the motor area of the affected hemisphere. This asymmetry seems negatively associated with time since amputation. For TMS data, only the ICF ratio is negatively correlated with PLP intensity (r = -0.25, p = 0.04). CONCLUSION There is an asymmetrical reorganization of the motor cortex in patients with PLP, characterized by a disorganized, widespread, and shifted hand cortical representation and a loss in grey matter volume in the affected hemisphere. This reorganization seems to reduce across time since amputation. However, it is not associated with pain intensity. SIGNIFICANCE These findings are significant to understand the role of the motor cortex reorganization in patients with PLP, showing that the pain intensity may be related with other neurophysiological factors, not just cortical reorganization.
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Affiliation(s)
- K Pacheco-Barrios
- Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Universidad San Ignacio de Loyola, Vicerrectorado de Investigación, Unidad de Investigación para la Generación y Síntesis de Evidencias en Salud, Lima, Peru
| | - C B Pinto
- Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - F G Saleh Velez
- Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; University of Chicago Medical Center, Department of Neurology, University of Chicago, Chicago, IL, USA
| | - D Duarte
- Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Psychiatry and Behavioural Neurosciences, McMaster University, Canada
| | - M E Gunduz
- Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - M Simis
- Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - A C Lepesteur Gianlorenco
- Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - J L Barouh
- Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - D Crandell
- Spaulding Rehabilitation Hospital, Harvard Medical School, Boston, MA, USA
| | - M Guidetti
- Università degli Studi di Milano, Dipartimento di scienze della Salute, "Aldo Ravelli" Center for Neurotechnolgy and Experimental Brain Therapeutics, Milano, Italy
| | - L Battistella
- Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - F Fregni
- Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
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Limakatso K, Madden VJ, Manie S, Parker R. The effectiveness of graded motor imagery for reducing phantom limb pain in amputees: a randomised controlled trial. Physiotherapy 2020; 109:65-74. [PMID: 31992445 DOI: 10.1016/j.physio.2019.06.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 04/10/2019] [Accepted: 06/24/2019] [Indexed: 10/26/2022]
Abstract
OBJECTIVE To investigate whether graded motor imagery (GMI) is effective for reducing phantom limb pain (PLP) in people who have undergone limb amputations. DESIGN A single-blinded randomised, controlled trial. SETTING Physiotherapy out-patient departments in three secondary level hospitals in Cape Town, South Africa. PARTICIPANTS Twenty-one adults (≥18 years) who had undergone unilateral upper or lower limb amputations and had self-reported PLP persisting beyond three months. INTERVENTIONS A 6-week GMI programme was compared to routine physiotherapy. The study outcomes were evaluated at baseline, 6 weeks, 3 months and 6 months. OUTCOME MEASURES The pain severity scale of the Brief Pain Inventory (BPI) was used to assess the primary outcome - PLP. The pain interference scale of the BPI and the EuroQol EQ-5D-5L were used to assess the secondary outcomes - pain interference with function and health-related quality of life (HRQoL) respectively. RESULTS The participants in the experimental group had significantly greater improvements in pain than the control group at 6 weeks and 6 months. Further, the participants in the experimental group had significantly greater improvements than the control group in pain interference at all follow-up points. There was no between-group difference in HRQoL. CONCLUSION The results of the current study suggest that GMI is better than routine physiotherapy for reducing PLP. Based on the significant reduction in PLP and pain interference within the participants who received GMI, and the ease of application, GMI may be a viable treatment for treating PLP in people who have undergone limb amputations. CLINICAL TRIAL REGISTRATION NUMBER (PACTR201701001979279).
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Affiliation(s)
- Katleho Limakatso
- Pain Management Unit, Department of Anaesthesia and Perioperative Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Victoria J Madden
- Pain Management Unit, Department of Anaesthesia and Perioperative Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa; Department of Psychiatry and Mental Health, Faculty of Health Sciences, University of Cape Town, Groote Schuur Hospital, Cape Town, South Africa
| | - Shamila Manie
- Division of Physiotherapy, Department of Health and Rehabilitation Sciences, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Romy Parker
- Pain Management Unit, Department of Anaesthesia and Perioperative Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa; Division of Physiotherapy, Department of Health and Rehabilitation Sciences, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.
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Buchheit T, Hsia HLJ, Cooter M, Shortell C, Kent M, McDuffie M, Shaw A, Buckenmaier CT, Van de Ven T. The Impact of Surgical Amputation and Valproic Acid on Pain and Functional Trajectory: Results from the Veterans Integrated Pain Evaluation Research (VIPER) Randomized, Double-Blinded Placebo-Controlled Trial. PAIN MEDICINE 2019; 20:2004-2017. [PMID: 31045229 DOI: 10.1093/pm/pnz067] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To determine if the perioperative administration of valproic acid reduces the incidence of chronic pain three months after amputation or revision surgery. DESIGN Multicenter, randomized, double-blind, placebo-controlled trial. SETTING Academic, military, and veteran medical centers. SUBJECTS One hundred twenty-eight patients undergoing amputation or amputation revision surgery at Duke University Hospital, Walter Reed National Military Medical Center, or the Durham Veterans Affairs Medical Center for either medical disease or trauma. METHODS Patients were randomized to placebo or valproic acid for the duration of hospitalization and treated with multimodal analgesic care, including regional anesthetic blockade. Primary outcome was the proportion of patients with chronic pain at three months (average numeric pain score intensity of 3/10 or greater). Secondary outcomes included functional trajectories (assessed with the Brief Pain Inventory short form and the Defense and Veterans Pain Rating Scale). RESULTS The overall rate of chronic pain was 68.2% in the 107 patients who completed the end point assessment. There was no significant effect of perioperative valproic acid administration, with a rate of 65.45% (N = 36) in the treatment group and a rate of 71.15% (N = 37) in the placebo group. Overall, pain scores decreased from baseline to follow-up (median = -2 on the numeric pain scale). Patients additionally experienced improvements in self-perceived function. CONCLUSIONS The rate of chronic pain after amputation surgery is not significantly improved with the perioperative administration of valproic acid. In this cohort treated with multimodal perioperative analgesia and regional anesthetic blockade, we observed improvements in both pain severity and function.
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Affiliation(s)
- Thomas Buchheit
- Department of Anesthesiology, Duke University Medical Center, Durham VA Medical Center, Durham, North Carolina
| | - Hung-Lun John Hsia
- Department of Anesthesiology, Duke University Medical Center, Durham VA Medical Center, Durham, North Carolina
| | | | - Cynthia Shortell
- Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | | | - Mary McDuffie
- Walter Reed National Military Medical Center, Defense and Veterans Center for Integrative Pain Management, Rockville, MD, USA
| | - Andrew Shaw
- Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Chester Trip Buckenmaier
- Department of Military Emergency Medicine, Defense and Veterans Center for Integrative Pain Management, Uniformed Services University, Bethesda, MD, USA
| | - Thomas Van de Ven
- Department of Anesthesiology, Duke University Medical Center, Durham VA Medical Center, Durham, North Carolina
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15
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Belinskaia DA, Belinskaia MA, Barygin OI, Vanchakova NP, Shestakova NN. Psychotropic Drugs for the Management of Chronic Pain and Itch. Pharmaceuticals (Basel) 2019; 12:ph12020099. [PMID: 31238561 PMCID: PMC6631469 DOI: 10.3390/ph12020099] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Revised: 06/19/2019] [Accepted: 06/21/2019] [Indexed: 12/11/2022] Open
Abstract
Clinical observations have shown that patients with chronic neuropathic pain or itch exhibit symptoms of increased anxiety, depression and cognitive impairment. Such patients need corrective therapy with antidepressants, antipsychotics or anticonvulsants. It is known that some psychotropic drugs are also effective for the treatment of neuropathic pain and pruritus syndromes due to interaction with the secondary molecular targets. Our own clinical studies have identified antipruritic and/or analgesic efficacy of the following compounds: tianeptine (atypical tricyclic antidepressant), citalopram (selective serotonin reuptake inhibitor), mianserin (tetracyclic antidepressant), carbamazepine (anticonvulsant), trazodone (serotonin antagonist and reuptake inhibitor), and chlorprothixene (antipsychotic). Venlafaxine (serotonin-norepinephrine reuptake inhibitor) is known to have an analgesic effect too. The mechanism of such effect of these drugs is not fully understood. Herein we review and correlate the literature data on analgesic/antipruritic activity with pharmacological profile of these compounds.
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Affiliation(s)
- Daria A Belinskaia
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Torez 44, St. Petersburg 194223, Russia.
| | - Mariia A Belinskaia
- International Centre for Neurotherapeutics, Dublin City University, Glasnevin, Dublin 9, Ireland.
| | - Oleg I Barygin
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Torez 44, St. Petersburg 194223, Russia.
| | - Nina P Vanchakova
- Department of Pedagogy and Psychology, Faculty of Postgraduate Education, First Pavlov State Medical University, L'va Tolstogo str. 6-8, St. Petersburg 197022, Russia.
| | - Natalia N Shestakova
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Torez 44, St. Petersburg 194223, Russia.
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A Systematic Review of NMDA Receptor Antagonists for Treatment of Neuropathic Pain in Clinical Practice. Clin J Pain 2019; 34:450-467. [PMID: 28877137 DOI: 10.1097/ajp.0000000000000547] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE To investigate the efficacy of N-methyl-D-aspartate receptor (NMDAR) antagonists for neuropathic pain (NeuP) and review literature to determine if specific pharmacologic agents provide adequate NeuP relief. METHODS Literature was reviewed on PubMed using a variety of key words for 8 NMDAR antagonists. These key words include: "Ketamine and Neuropathy," "Ketamine and Neuropathic Pain," "Methadone and Neuropathy," "Methadone and Neuropathic Pain," "Memantine and Neuropathic pain," "Memantine and Neuropathy," "Amantadine and Neuropathic Pain," "Amantadine and Neuropathy," "Dextromethorphan and Neuropathic Pain," "Dextromethorphan and Neuropathy," "Carbamazepine and Neuropathic Pain," "Carbamazepine and Neuropathy," "Valproic Acid and Neuropathy," "Valproic Acid and Neuropathic Pain," "Phenytoin and Neuropathy," and "Phenytoin and Neuropathic Pain." With the results, the papers were reviewed using the PRISMA (Preferred Reporting in Systematic and Meta-Analyses) guideline. RESULTS A total of 58 randomized controlled trials were reviewed among 8 pharmacologic agents, which are organized by date and alphabetical order. Of the trials for ketamine, 15 showed some benefit for analgesia. Methadone had 3 positive trials, while amantadine and memantine each only had 2 trials showing NeuP analgesic properties. Dextromethorphan and valproic acid both had 4 randomized controlled trials that showed some NeuP treatment benefit while carbamazepine had over 8 trials showing efficacy. Finally, phenytoin only had 1 trial that showed clinical response in treatment. CONCLUSIONS There are a variety of NMDAR antagonist agents that should be considered for treatment of NeuP. Nevertheless, continued and further investigation of the 8 pharmacologic agents is needed to continue to evaluate their efficacy for treatment of NeuP.
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Kurian R, Raza K, Shanthanna H. A systematic review and meta-analysis of memantine for the prevention or treatment of chronic pain. Eur J Pain 2019; 23:1234-1250. [PMID: 30848504 DOI: 10.1002/ejp.1393] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 02/10/2019] [Accepted: 03/03/2019] [Indexed: 12/21/2022]
Abstract
BACKGROUND AND OBJECTIVE N-methyl-D-aspartate (NMDA) receptors are involved in pain signalling and neuroplasticity. Memantine has been shown to have analgesic properties in pre-clinical and small clinical studies. We conducted a systematic review and meta-analysis to assess the efficacy of memantine to prevent or reduce chronic pain. DATABASES AND DATA TREATMENT MEDLINE, EMBASE and CENTRAL databases were searched for comparative trials using memantine, either against placebo or active medications, for chronic pain in adults. Pain relief was considered our primary outcome. Meta-analyses were conducted if outcomes were reported in two or more studies. Outcomes were reported as mean differences (MD) or risk ratios (RR) with 95% confidence intervals (CI). Quality was assessed using the GRADE approach. RESULTS Among 454 citations, 15 studies were included with populations predominantly consisting of neuropathic conditions and fibromyalgia. Overall, we observed unclear reporting of randomization and allocation methods, apart from potential for publication bias. Among the 11 studies looking at chronic pain treatment, the difference in end pain score with memantine was not significant: MD = -0.58 units (95% CI -1.31, 0.14); I2 = 82% (low quality). In two surgical studies using memantine for pain prevention, memantine decreased pain intensity: MD = -1.02 units (95% CI -1.38, -0.66); I2 = 0%. Dizziness was significantly more common with memantine: RR = 4.90 (95% CI 1.26, 18.99); I2 = 52% (moderate quality). CONCLUSION The current evidence regarding the use of memantine for chronic pain is limited and uncertain. Despite its potential, pain relief achieved in clinical studies is small and is associated with an increase in dizziness. SIGNIFICANCE Despite a sound rationale, the benefit of using memantine for chronic pain is unclear. Our systematic review and meta-analysis show that memantine may have the potential to decrease pain. However, it can also increase common adverse effects. Considering the small number of studies with potential for bias and inconclusive evidence, there was low to very low certainty. Hence, no clear recommendations can be made about its routine clinical use until larger and more definitive studies are conducted.
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Affiliation(s)
- Rouvin Kurian
- McMaster School of Interdisciplinary Science, Faculty of Science, McMaster University, Hamilton, Ontario, Canada
| | - Kazim Raza
- Department of Anesthesiology, Michael DeGroote School of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Harsha Shanthanna
- Department of Anesthesiology, Michael DeGroote School of Medicine, McMaster University, Hamilton, Ontario, Canada
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18
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Abstract
Pain management is complex regardless of whether the pain is acute or chronic in nature or non-cancer or cancer related. In addition, relatively few pain pharmacotherapy options with adequate efficacy and safety data currently exist. Consequently, interest in the role of NMDA receptor antagonists as a pharmacological pain management strategy has surfaced. This narrative review provides an overview of the NMDA receptor and elaborates on the pharmacotherapeutic profile and pain management literature findings for the following NMDA receptor antagonists: ketamine, memantine, dextromethorphan, and magnesium. The literature on this topic is characterized by small studies, many of which exhibit methodological flaws. To date, ketamine is the most studied NMDA receptor antagonist for both acute and chronic pain management. Although further research about NMDA receptor antagonists for analgesia is needed and the optimal dosage/administration regimens for these drugs have yet to be determined, ketamine appears to hold the most promise and may be of particular value in the perioperative pain management realm.
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Abstract
OBJECTIVE To review the literature related to different treatment strategies for the general population of individuals with amputation, spinal cord injury, and cerebral palsy, as well as how this may impact pain management in a correlated athlete population. DATA SOURCES A comprehensive literature search was performed linking pain with terms related to different impairment types. MAIN RESULTS There is a paucity in the literature relating to treatment of pain in athletes with impairment; however, it is possible that the treatment strategies used in the general population of individuals with impairment may be translated to the athlete population. There are a wide variety of treatment options including both pharmacological and nonpharmacological treatments which may be applicable in the athlete. CONCLUSIONS It is the role of the physician to determine which strategy of the possible treatment options will best facilitate the management of pain in the individual athlete in a sport-specific setting.
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20
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El-Hagrassy MM, Duarte DGG, Thibaut A, Lucena MFG, Fregni F. Principles of designing a clinical trial: optimizing chances of trial success. Curr Behav Neurosci Rep 2018; 5:143-152. [PMID: 30467533 PMCID: PMC6241291 DOI: 10.1007/s40473-018-0152-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
PURPOSE OF REVIEW Clinical trials are essential to advance health care and develop new therapies. In this review we discuss the underlying principles of clinical trial design with an emphasis on assessing design risks that lead to trial failure as well as negative trials. While of general interest, this is perhaps particularly timely for the neuromodulation community, given the paucity of well-designed trials in the field. We give some examples from the phantom limb pain (PLP) literature. RECENT FINDINGS It is critical to gather as much preliminary data as possible and to know how to interpret it in order to choose an appropriate trial design. Therefore, the investigator needs to effectively assess the likely trial design risk/benefit ratio with a view to maximizing the chance of a meaningful outcome, whether this outcome rejects or fails to reject the null hypothesis. This analysis is especially important in a complex and heterogeneous disorder such as PLP, which has had many negative trials. SUMMARY We discuss the factors pertaining to a strong trial design benefit/risk assessment, how late trial phases require greater support from preliminary data, how to design trials to minimize risks, maximize benefits, and optimize internal validity as well as the chances of a positive outcome. We highlight the need for investigators to incorporate best practice in trial design to increase the chances of success, to always anticipate unexpected challenges during the trial.
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Affiliation(s)
- Mirret M. El-Hagrassy
- Neuromodulation Center, Spaulding Rehabilitation Hospital, Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA, United States
| | - Dante G. G. Duarte
- Neuromodulation Center, Spaulding Rehabilitation Hospital, Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA, United States
| | - Aurore Thibaut
- Neuromodulation Center, Spaulding Rehabilitation Hospital, Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA, United States
- Coma Science Group, GIGA-Research, University and University Hospital of Liege, Liege, Belgium
| | - Mariana F. G. Lucena
- Neuromodulation Center, Spaulding Rehabilitation Hospital, Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA, United States
| | - Felipe Fregni
- Neuromodulation Center, Spaulding Rehabilitation Hospital, Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA, United States
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Collins KL, Russell HG, Schumacher PJ, Robinson-Freeman KE, O'Conor EC, Gibney KD, Yambem O, Dykes RW, Waters RS, Tsao JW. A review of current theories and treatments for phantom limb pain. J Clin Invest 2018; 128:2168-2176. [PMID: 29856366 DOI: 10.1172/jci94003] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Following amputation, most amputees still report feeling the missing limb and often describe these feelings as excruciatingly painful. Phantom limb sensations (PLS) are useful while controlling a prosthesis; however, phantom limb pain (PLP) is a debilitating condition that drastically hinders quality of life. Although such experiences have been reported since the early 16th century, the etiology remains unknown. Debate continues regarding the roles of the central and peripheral nervous systems. Currently, the most posited mechanistic theories rely on neuronal network reorganization; however, greater consideration should be given to the role of the dorsal root ganglion within the peripheral nervous system. This Review provides an overview of the proposed mechanistic theories as well as an overview of various treatments for PLP.
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Affiliation(s)
| | - Hannah G Russell
- Department of Neurology, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Patrick J Schumacher
- Department of Neurology, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | | | - Ellen C O'Conor
- Department of Neurology, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Kyla D Gibney
- Department of Neurology, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Olivia Yambem
- Department of Neurology, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Robert W Dykes
- School of Physical and Occupational Therapy, McGill University, Montreal, Quebec, Canada
| | | | - Jack W Tsao
- Department of Neurology, University of Tennessee Health Science Center, Memphis, Tennessee, USA.,Department of Neurology, Memphis Veterans Affairs Medical Center, Memphis, Tennessee, USA.,Children's Foundation Research Institute, Le Bonheur Children's Hospital, Memphis, Tennessee, USA
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Greenwald JD, Shafritz KM. An Integrative Neuroscience Framework for the Treatment of Chronic Pain: From Cellular Alterations to Behavior. Front Integr Neurosci 2018; 12:18. [PMID: 29875641 PMCID: PMC5974053 DOI: 10.3389/fnint.2018.00018] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 05/04/2018] [Indexed: 12/21/2022] Open
Abstract
Chronic pain can result from many pain syndromes including complex regional pain syndrome (CRPS), phantom limb pain and chronic low back pain, among others. On a molecular level, chronic pain syndromes arise from hypersensitization within the dorsal horn of the spinal cord, a process known as central sensitization. Central sensitization involves an upregulation of ionotropic and metabotropic glutamate receptors (mGluRs) similar to that of long-term potentiation (LTP). Regions of the brain in which LTP occurs, such as the amygdala and hippocampus, are implicated in fear- and memory-related brain circuity. Chronic pain dramatically influences patient quality of life. Individuals with chronic pain may develop pain-related anxiety and pain-related fear. The syndrome also alters functional connectivity in the default-mode network (DMN) and salience network. On a cellular/molecular level, central sensitization may be reversed through degradative glutamate receptor pathways. This, however, rarely happens. Instead, cortical brain regions may serve in a top-down regulatory capacity for the maintenance or alleviation of pain. Specifically, the medial prefrontal cortex (mPFC), which plays a critical role in fear-related brain circuits, the DMN, and salience network may be the driving forces in this process. On a cellular level, the mPFC may form new neural circuits through LTP that may cause extinction of pre-existing pain pathways found within fear-related brain circuits, the DMN, and salience network. In order to promote new LTP connections between the mPFC and other key brain structures, such as the amygdala and insula, we propose a holistic rehabilitation program including cognitive behavioral therapy (CBT) and revolving around: (1) cognitive reappraisals; (2) mindfulness meditation; and (3) functional rehabilitation. Unlike current medical interventions focusing upon pain-relieving medications, we do not believe that chronic pain treatment should focus on reversing the effects of central sensitization. Instead, we propose here that it is critical to focus on non-invasive efforts to promote new neural circuits originating from the mPFC.
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Affiliation(s)
- Jess D. Greenwald
- Department of Psychology, Hofstra University, Hempstead, NY, United States
| | - Keith M. Shafritz
- Department of Psychology, Hofstra University, Hempstead, NY, United States
- Center for Psychiatric Neuroscience, The Feinstein Institute for Medical Research, Manhasset, NY, United States
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23
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Pickering G, Morel V. Memantine for the treatment of general neuropathic pain: a narrative review. Fundam Clin Pharmacol 2017; 32:4-13. [DOI: 10.1111/fcp.12316] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 07/04/2017] [Accepted: 08/10/2017] [Indexed: 12/26/2022]
Affiliation(s)
- Gisèle Pickering
- CHU Clermont-Ferrand; Centre de Pharmacologie Clinique; F-63003 Clermont-Ferrand France
- Inserm, CIC 1405; Neurodol 1107 F-63003 Clermont-Ferrand France
- Laboratoire de Pharmacologie; Faculté de Médecine; Clermont Université; F-63001 Clermont-Ferrand France
| | - Véronique Morel
- CHU Clermont-Ferrand; Centre de Pharmacologie Clinique; F-63003 Clermont-Ferrand France
- Inserm, CIC 1405; Neurodol 1107 F-63003 Clermont-Ferrand France
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Wylde V, Dennis J, Beswick AD, Bruce J, Eccleston C, Howells N, Peters TJ, Gooberman‐Hill R. Systematic review of management of chronic pain after surgery. Br J Surg 2017; 104:1293-1306. [PMID: 28681962 PMCID: PMC5599964 DOI: 10.1002/bjs.10601] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 01/24/2017] [Accepted: 04/21/2017] [Indexed: 12/24/2022]
Abstract
BACKGROUND Pain present for at least 3 months after a surgical procedure is considered chronic postsurgical pain (CPSP) and affects 10-50 per cent of patients. Interventions for CPSP may focus on the underlying condition that indicated surgery, the aetiology of new-onset pain or be multifactorial in recognition of the diverse causes of this pain. The aim of this systematic review was to identify RCTs of interventions for the management of CPSP, and synthesize data across treatment type to estimate their effectiveness and safety. METHODS MEDLINE, Embase, PsycINFO, CINAHL and the Cochrane Library were searched from inception to March 2016. Trials of pain interventions received by patients at 3 months or more after surgery were included. Risk of bias was assessed using the Cochrane risk-of-bias tool. RESULTS Some 66 trials with data from 3149 participants were included. Most trials included patients with chronic pain after spinal surgery (25 trials) or phantom limb pain (21 trials). Interventions were predominantly pharmacological, including antiepileptics, capsaicin, epidural steroid injections, local anaesthetic, neurotoxins, N-methyl-d-aspartate receptor antagonists and opioids. Other interventions included acupuncture, exercise, postamputation limb liner, spinal cord stimulation, further surgery, laser therapy, magnetic stimulation, mindfulness-based stress reduction, mirror therapy and sensory discrimination training. Opportunities for meta-analysis were limited by heterogeneity. For all interventions, there was insufficient evidence to draw conclusions on effectiveness. CONCLUSION There is a need for more evidence about interventions for CPSP. High-quality trials of multimodal interventions matched to pain characteristics are needed to provide robust evidence to guide management of CPSP.
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Affiliation(s)
- V. Wylde
- Musculoskeletal Research Unit, School of Clinical SciencesUniversity of BristolBristolUK
| | - J. Dennis
- Musculoskeletal Research Unit, School of Clinical SciencesUniversity of BristolBristolUK
| | - A. D. Beswick
- Musculoskeletal Research Unit, School of Clinical SciencesUniversity of BristolBristolUK
| | - J. Bruce
- Warwick Clinical Trials UnitUniversity of WarwickWarwickUK
| | - C. Eccleston
- Centre for Pain ResearchUniversity of BathBathUK
- Department of Experimental‐Clinical and Health PsychologyGhent UniversityGhentBelgium
| | - N. Howells
- Avon Orthopaedic Centre, Department of Trauma and OrthopaedicsNorth Bristol NHS TrustBristolUK
| | - T. J. Peters
- Musculoskeletal Research Unit, School of Clinical SciencesUniversity of BristolBristolUK
| | - R. Gooberman‐Hill
- Musculoskeletal Research Unit, School of Clinical SciencesUniversity of BristolBristolUK
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Richardson C, Kulkarni J. A review of the management of phantom limb pain: challenges and solutions. J Pain Res 2017; 10:1861-1870. [PMID: 28860841 PMCID: PMC5558877 DOI: 10.2147/jpr.s124664] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Phantom limb pain (PLP) occurs in 50% and 80% of amputees. Although it is often classified as a neuropathic pain, few of the large-scale trials of treatments for neuropathic pain included sufficient numbers of PLP sufferers to have confidence that they are effective in this condition. Many therapies have been administered to amputees with PLP over the years; however, as of yet, there appears to be no first-line treatment. OBJECTIVES To comprehensively review the literature on treatment modalities for PLP and to identify the challenges currently faced by clinicians dealing with this pain. METHOD MEDLINE, EMBASE, CINAHL, British Nursing Index, Cochrane and psycINFO databases were searched using "Phantom limb" initially as a MeSH term to identify treatments that had been tried. Then, a secondary search combining phantom limb with each treatment was performed to find papers specific to each therapy. Each paper was assessed for its research strength using the GRADE system. RESULTS Thirty-eight therapies were identified. Overall, the quality of evidence was low. There was one high-quality study which used repetitive transcutaneous magnetic stimulation and found a statistical reduction in pain at day 15 but no difference at day 30. Significant results from single studies of moderate level quality were available for gabapentin, ketamine and morphine; however, there was a risk of bias in these papers. Mirror therapy and associated techniques were assessed through two systematic reviews, which conclude that there is insufficient evidence to support their use. CONCLUSION No decisions can be made for the first-line management of PLP, as the level of evidence is too low. Robust studies on homogeneous populations, an understanding of what amputees consider a meaningful reduction in PLP and agreement of whether pain intensity is the legitimate therapeutic target are urgently required.
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Affiliation(s)
- Cliff Richardson
- University of Manchester, Division of Nursing Midwifery and Social Work, Manchester, UK
| | - Jai Kulkarni
- Specialized Ability Centre (Manchester), University Hospitals of South Manchester NHS Foundation Trust, Manchester, UK
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Privitera R, Birch R, Sinisi M, Mihaylov IR, Leech R, Anand P. Capsaicin 8% patch treatment for amputation stump and phantom limb pain: a clinical and functional MRI study. J Pain Res 2017; 10:1623-1634. [PMID: 28761369 PMCID: PMC5516883 DOI: 10.2147/jpr.s140925] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Purpose The aim of this study was to measure the efficacy of a single 60 min application of capsaicin 8% patch in reducing chronic amputation stump and phantom limb pain, associated hypersensitivity with quantitative sensory testing, and changes in brain cortical maps using functional MRI (fMRI) scans. Methods A capsaicin 8% patch (Qutenza) treatment study was conducted on 14 patients with single limb amputation, who reported pain intensity on the Numerical Pain Rating Scale ≥4/10 for chronic stump or phantom limb pain. Pain assessments, quantitative sensory testing, and fMRI (for the lip pursing task) were performed at baseline and 4 weeks after application of capsaicin 8% patch to the amputation stump. The shift into the hand representation area of the cerebral cortex with the lip pursing task has been correlated with phantom limb pain intensity in previous studies, and was the fMRI clinical model for cortical plasticity used in this study. Results The mean reduction in spontaneous amputation stump pain, phantom limb pain, and evoked stump pain were −1.007 (p=0.028), −1.414 (p=0.018), and −2.029 (p=0.007), respectively. The areas of brush allodynia and pinprick hypersensitivity in the amputation stump showed marked decreases: −165 cm2, −80% (p=0.001) and −132 cm2, −72% (p=0.001), respectively. fMRI analyses provided objective evidence of the restoration of the brain map, that is, reversal of the shift into the hand representation of the cerebral cortex with the lip pursing task (p<0.05). Conclusion The results show that capsaicin 8% patch treatment leads to significant reduction in chronic pain and, particularly, in the area of stump hypersensitivity, which may enable patients to wear prostheses, thereby improving mobility and rehabilitation. Phantom limb pain (“central” pain) and associated brain plasticity may be modulated by peripheral inputs, as they can be ameliorated by the peripherally restricted effect of the capsaicin 8% patch.
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Affiliation(s)
- Rosario Privitera
- Peripheral Neuropathy Unit, Centre for Clinical Translation, Hammersmith Hospital, Imperial College London, London, UK
| | - Rolfe Birch
- Peripheral Neuropathy Unit, Centre for Clinical Translation, Hammersmith Hospital, Imperial College London, London, UK
| | - Marco Sinisi
- Peripheral Nerve Injury Unit, Royal National Orthopaedic Hospital, Stanmore, Middlesex, UK
| | - Iordan R Mihaylov
- Department of Pain Medicine, Royal National Orthopaedic Hospital NHS Trust, Stanmore, UK
| | - Robert Leech
- Computational, Cognitive and Clinical Neuroimaging Laboratory, Division of Brain Sciences, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Praveen Anand
- Peripheral Neuropathy Unit, Centre for Clinical Translation, Hammersmith Hospital, Imperial College London, London, UK
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Loy BM, Britt RB, Brown JN. Memantine for the Treatment of Phantom Limb Pain: A Systematic Review. J Pain Palliat Care Pharmacother 2016; 30:276-283. [DOI: 10.1080/15360288.2016.1241334] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Abstract
BACKGROUND This is an updated version of the original Cochrane review published in Issue 12, 2011. Phantom limb pain (PLP) is pain that arises in the missing limb after amputation and can be severe, intractable, and disabling. Various medications have been studied in the treatment of phantom pain. There is currently uncertainty in the optimal pharmacologic management of PLP. OBJECTIVES This review aimed to summarise the evidence of effectiveness of pharmacologic interventions in treating PLP. SEARCH METHODS For this update, we searched the Cochrane Central Register of Controlled Trials (CENTRAL, the Cochrane Library), MEDLINE, and Embase for relevant studies. We ran the searches for the original review in September 2011 and subsequent searches for this update up to April 2016. We sought additional studies from clinical trials databases and reference lists of retrieved papers. SELECTION CRITERIA We included randomised and quasi-randomised trials studying the effectiveness of pharmacologic interventions compared with placebo, another active treatment, or no treatment, in established PLP. We considered the following outcomes: change in pain intensity, function, sleep, depression or mood, quality of life, adverse events, treatment satisfaction, and withdrawals from the study. DATA COLLECTION AND ANALYSIS We independently assessed issues of study quality and extracted efficacy and adverse event data. Due to the wide variability in the studies, we did not perform a meta-analysis for all the interventions and outcomes, but attempted to pool the results of some studies where possible. We prepared a qualitative description and narrative summary of results. We assessed clinical heterogeneity by making qualitative comparisons of the populations, interventions, outcomes/outcome measures, and methods. MAIN RESULTS We added only one new study with 14 participants to this updated review. We included a 14 studies (10 with low risk of bias and 4 with unclear risk of bias overall) with a total of 269 participants. We added another drug class, botulinum neurotoxins (BoNTs), in particular botulinum toxin A (BoNT/A), to the group of medications reviewed previously. Our primary outcome was change in pain intensity. Most studies did not report our secondary outcomes of sleep, depression or mood, quality of life, treatment satisfaction, or withdrawals from the study.BoNT/A did not improve phantom limb pain intensity during the six months of follow-up compared with lidocaine/methylprednisolone.Compared with placebo, morphine (oral and intravenous) was effective in decreasing pain intensity in the short term with reported adverse events being constipation, sedation, tiredness, dizziness, sweating, voiding difficulty, vertigo, itching, and respiratory problems.The N-methyl D-aspartate (NMDA) receptor antagonists ketamine (versus placebo; versus calcitonin) and dextromethorphan (versus placebo), but not memantine, had analgesic effects. The adverse events of ketamine were more serious than placebo and calcitonin and included loss of consciousness, sedation, hallucinations, hearing and position impairment, and insobriety.The results for gabapentin in terms of pain relief were conflicting, but combining the results favoured treatment group (gabapentin) over control group (placebo) (mean difference -1.16, 95% confidence interval -1.94 to -0.38; 2 studies). However, gabapentin did not improve function, depression score, or sleep quality. Adverse events experienced were somnolence, dizziness, headache, and nausea.Compared with an active control benztropine mesylate, amitriptyline was not effective in PLP, with dry mouth and dizziness as the most frequent adverse events based on one study.The findings for calcitonin (versus placebo; versus ketamine) and local anaesthetics (versus placebo) were variable. Adverse events of calcitonin were headache, vertigo, drowsiness, nausea, vomiting, and hot and cold flushes. Most of the studies were limited by their small sample sizes. AUTHORS' CONCLUSIONS Since the last version of this review, we identified another study that added another form of medical therapy, BoNTs, specifically BoNT/A, to the list of pharmacologic interventions being reviewed for clinical efficacy in phantom limb pain. However, the results of this study did not substantially change the main conclusions. The short- and long-term effectiveness of BoNT/A, opioids, NMDA receptor antagonists, anticonvulsants, antidepressants, calcitonins, and local anaesthetics for clinically relevant outcomes including pain, function, mood, sleep, quality of life, treatment satisfaction, and adverse events remain unclear. Based on a small study, BoNT/A (versus lidocaine/methylprednisolone) does not decrease phantom limb pain. Morphine, gabapentin, and ketamine demonstrate favourable short-term analgesic efficacy compared with placebo. Memantine and amitriptyline may not be effective for PLP. However, results must be interpreted with caution, as they were based mostly on a small number of studies with limited sample sizes that varied considerably and also lacked long-term efficacy and safety outcomes. The direction of efficacy of calcitonin, local anaesthetics, and dextromethorphan needs further clarification. Overall, the efficacy evidence for the reviewed medications is thus far inconclusive. Larger and more rigorous randomised controlled trials are needed for us to reach more definitive conclusions about which medications would be useful for clinical practice.
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Affiliation(s)
- Maria Jenelyn M Alviar
- University of Melbourne-Royal Melbourne Hospital, Grattan St, Melbourne, Victoria, Australia, 3010
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Morel V, Joly D, Villatte C, Dubray C, Durando X, Daulhac L, Coudert C, Roux D, Pereira B, Pickering G. Memantine before Mastectomy Prevents Post-Surgery Pain: A Randomized, Blinded Clinical Trial in Surgical Patients. PLoS One 2016; 11:e0152741. [PMID: 27050431 PMCID: PMC4822967 DOI: 10.1371/journal.pone.0152741] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 03/18/2016] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Neuropathic pain following surgical treatment for breast cancer with or without chemotherapy is a clinical burden and patients frequently report cognitive, emotional and quality of life impairment. A preclinical study recently showed that memantine administered before surgery may prevent neuropathic pain development and cognitive dysfunction. With a translational approach, a clinical trial has been carried out to evaluate whether memantine administered before and after mastectomy could prevent the development of neuropathic pain, the impairment of cognition and quality of life. METHOD A randomized, pilot clinical trial included 40 women undergoing mastectomy in the Oncology Department, University Hospital, Clermont-Ferrand, France. Memantine (5 to 20 mg/day; n = 20) or placebo (n = 20) was administered for four weeks starting two weeks before surgery. The primary endpoint was pain intensity measured on a (0-10) numerical rating scale at three months post-mastectomy. RESULTS Data analyses were performed using mixed models and the tests were two-sided, with a type I error set at α = 0.05. Compared with placebo, patients receiving memantine showed at three months a significant difference in post-mastectomy pain intensity, less rescue analgesia and a better emotional state. An improvement of pain symptoms induced by cancer chemotherapy was also reported. CONCLUSIONS This study shows for the first time the beneficial effect of memantine to prevent post-mastectomy pain development and to diminish chemotherapy-induced pain symptoms. The lesser analgesic consumption and better well-being of patients for at least six months after treatment suggests that memantine could be an interesting therapeutic option to diminish the burden of breast cancer therapy. TRIAL REGISTRATION Clinicaltrials.gov NCT01536314.
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Affiliation(s)
- Véronique Morel
- CHU Clermont-Ferrand, Inserm CIC 1405, Centre de Pharmacologie Clinique, F-63003 Clermont-Ferrand, France
| | - Dominique Joly
- Centre Jean Perrin, Centre de Lutte contre le Cancer, 58 rue Montalembert, F-63000 Clermont-Ferrand, France
| | - Christine Villatte
- Centre Jean Perrin, Centre de Lutte contre le Cancer, 58 rue Montalembert, F-63000 Clermont-Ferrand, France
| | - Claude Dubray
- CHU Clermont-Ferrand, Inserm CIC 1405, Centre de Pharmacologie Clinique, F-63003 Clermont-Ferrand, France
- Clermont Université, Université d’Auvergne, Pharmacologie Fondamentale et Clinique de la Douleur, Laboratoire de Pharmacologie, Facultés de Médecine/Pharmacie, F-63000 Clermont-Ferrand, France
- Inserm, U1107 Neuro-Dol, F-63001 Clermont-Ferrand, France
| | - Xavier Durando
- Centre Jean Perrin, Centre de Lutte contre le Cancer, 58 rue Montalembert, F-63000 Clermont-Ferrand, France
| | - Laurence Daulhac
- Clermont Université, Université d’Auvergne, Pharmacologie Fondamentale et Clinique de la Douleur, Laboratoire de Pharmacologie, Facultés de Médecine/Pharmacie, F-63000 Clermont-Ferrand, France
- Inserm, U1107 Neuro-Dol, F-63001 Clermont-Ferrand, France
| | - Catherine Coudert
- CHU Clermont-Ferrand, Pharmacie Hospitalière, secteur Recherche Clinique - 58, rue Montalembert, F-63003 Clermont-Ferrand, France
| | - Delphine Roux
- CHU Clermont-Ferrand, Inserm CIC 1405, Centre de Pharmacologie Clinique, F-63003 Clermont-Ferrand, France
| | - Bruno Pereira
- CHU de Clermont-Ferrand, Délégation Recherche Clinique & Innovation - Villa annexe IFSI, 58 Rue Montalembert, F-63003 Clermont-Ferrand cedex, France
| | - Gisèle Pickering
- CHU Clermont-Ferrand, Inserm CIC 1405, Centre de Pharmacologie Clinique, F-63003 Clermont-Ferrand, France
- Clermont Université, Université d’Auvergne, Pharmacologie Fondamentale et Clinique de la Douleur, Laboratoire de Pharmacologie, Facultés de Médecine/Pharmacie, F-63000 Clermont-Ferrand, France
- Inserm, U1107 Neuro-Dol, F-63001 Clermont-Ferrand, France
- * E-mail:
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Abstract
PURPOSE OF REVIEW To provide an overview on drug targets and emerging pharmacological treatment options for chronic pain. RECENT FINDINGS Chronic pain poses an enormous socioeconomic burden for the more than 30% of people who suffer from it, costing over $600 billion per year in the USA. In recent years, there has been a surge in preclinical and clinical research endeavors to try to stem this epidemic. Preclinical studies have identified a wide array of potential targets, with some of the most promising translational research being performed on novel opioid receptors, cannabinoid receptors, selective ion channel blockers, cytokine inhibitors, nerve growth factor inhibitors, N-methyl-D-aspartate receptor antagonists, glial cell inhibitors, and bisphosphonates. SUMMARY There are many obstacles for the development of effective medications to treat chronic pain, including the inherent challenges in identifying pathophysiological mechanisms, the overlap and multiplicity of pain pathways, and off-target adverse effects stemming from the ubiquity of drug target receptor sites and the lack of highly selective receptor ligands. Despite these barriers, the number and diversity of potential therapies have continued to grow, to include disease-modifying and individualized drug treatments.
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Abstract
BACKGROUND Phantom limb pain (PLP) is a common complication after amputation, affecting up to 80% of the amputee population. However, only 5% to 10% of amputees have severe PLP impacting daily function. The present report details the management of severe, treatment-resistant PLP in a 72-year-old man with a traumatic left transradial amputation and a comorbid complication of heterotopic ossification (HO). OBJECTIVE To describe a case of PLP with HO and the possible role of calcitonin in the treatment of both conditions. METHODS A systematic review of the literature regarding the management of PLP. RESULTS Seventeen articles that directly addressed PLP were identified; 11 were randomized controlled trials. All involved small samples and follow-up ranged from 6 h to one year, with the majority limited to six weeks. DISCUSSION In the present case, medication management was limited by side effects, lack of response and the patient's desire to avoid long-term medication. Investigations revealed HO, which was suspected to envelop the median nerve in the proximal forearm. After several unsuccessful medication trials, the literature was reviewed in search of common variables between HO formation and persistent PLP. Ultimately, the biochemical effects associated with nerve injury were identified to be a possible factor in both HO and PLP development. Calcitonin's proposed mechanisms of action may help to manage HO and PLP at multiple stages of disease development and maintenance. In the present case, a four-week trial of intranasal calcitonin was successful, with pain control lasting at least 18 months. CONCLUSION The present case report provided a review of the current literature in PLP pharmacological management and the current understanding of the etiology of PLP and HO, as well as how the two may coexist. It also provided an opportunity to discuss the proposed mechanisms of action of calcitonin in the management of PLP and HO.
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Arakawa A, Kaneko M, Narukawa M. An Investigation of Factors Contributing to Higher Levels of Placebo Response in Clinical Trials in Neuropathic Pain: A Systematic Review and Meta-Analysis. Clin Drug Investig 2015; 35:67-81. [DOI: 10.1007/s40261-014-0259-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Efficacy of memantine in the treatment of fibromyalgia: A double-blind, randomised, controlled trial with 6-month follow-up. Pain 2014; 155:2517-2525. [DOI: 10.1016/j.pain.2014.09.004] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 07/09/2014] [Accepted: 09/03/2014] [Indexed: 11/23/2022]
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Pickering G, Morel V, Joly D, Villatte C, Roux D, Dubray C, Pereira B. Prevention of post-mastectomy neuropathic pain with memantine: study protocol for a randomized controlled trial. Trials 2014; 15:331. [PMID: 25142039 PMCID: PMC4148528 DOI: 10.1186/1745-6215-15-331] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 08/06/2014] [Indexed: 01/21/2023] Open
Abstract
Background N-methyl-D-aspartate receptor antagonists are potential therapies for neuropathic pain, and memantine has a good tolerance profile. A preclinical study recently reported that presurgery memantine may prevent neuropathic pain development and cognition dysfunction. Considering the high prevalence of breast cancer and of post-mastectomy neuropathic pain, a clinical trial is carried out to evaluate if memantine may prevent neuropathic pain development and maintain cognitive function and quality of life in cancer patients. Methods/Design A randomized clinical trial (NCT01536314) includes 40 women with breast cancer undergoing mastectomy at the Oncology Hospital, Clermont-Ferrand, France. Memantine (5 to 20 mg/day; n = 20) or placebo (n = 20) is administered for 4 weeks starting 2 weeks before surgery. Intensity of pain, cognitive function, quality of life and of sleep, anxiety and depression are evaluated with questionnaires. The primary endpoint is pain intensity on a 0 to 10) numerical scale at 3 months post-mastectomy. Data analysis is performed using mixed models and the tests are two-sided, with a type I error set at α = 0.05. Discussion The hypothesis of this translational approach is to confirm in patients the beneficial prophylactic effect of memantine observed in animals. Such a protective action of memantine against neuropathic pain and cognitive dysfunction would greatly improve the quality of life of cancer patients. Trial registration ClinicalTrials.gov: NCT01536314 on 16 February 2012
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Affiliation(s)
- Gisèle Pickering
- Clermont Université, Université d'Auvergne, Pharmacologie Fondamentale et Clinique de la Douleur, Laboratoire de Pharmacologie, Facultés de Médecine/Pharmacie, F-63000 Clermont-Ferrand, France.
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Tian S, Nick S, Wu H. Phantom limb pain: A review of evidence-based treatment options. World J Anesthesiol 2014; 3:146-153. [DOI: 10.5313/wja.v3.i2.146] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 01/11/2014] [Accepted: 03/12/2014] [Indexed: 02/06/2023] Open
Abstract
Phantom limb pain (PLP) is not uncommon after amputation. PLP is described as a painful sensation perceived in the missing limb. Despite of its complicated pathophysiology, high prevalence of PLP has been associated with poor health-related quality of life, low daily activity and short walking distances. A prompt and effective management of PLP is essential in caring for the amputee population. Current treatments including physical therapy, psychotherapy, medications, and interventions have been used with limited success. In this review, we provided an updated and evidence-based review of treatment options for PLP.
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Rationale and design of a multicenter randomized clinical trial with memantine and dextromethorphan in ketamine-responder patients. Contemp Clin Trials 2014; 38:314-20. [PMID: 24948402 DOI: 10.1016/j.cct.2014.06.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 06/03/2014] [Accepted: 06/05/2014] [Indexed: 01/29/2023]
Abstract
The N-methyl-D-aspartate receptor plays an important role in central sensitization of neuropathic pain and N-methyl-D-aspartate receptor antagonists, such as ketamine, memantine and dextromethorphan may be used for persistent pain. However, ketamine cannot be repeated too often because of its adverse events. A drug relay would be helpful in the outpatient to postpone or even cancel the next ketamine infusion. This clinical trial evaluates if memantine and/or dextromethorphan given as a relay to ketamine responders may maintain or induce a decrease of pain intensity and have a beneficial impact on cognition and quality of life. This trial is a multi-center, randomized, controlled and single-blind clinical study (NCT01602185). It includes 60 ketamine responder patients suffering from neuropathic pain. They are randomly allocated to memantine, dextromethorphan or placebo. After ketamine infusion, 60 patients received either memantine (maximal dose 20 mg/day), or dextromethorphan (maximal dose 90 mg/day), or placebo for 12 weeks. The primary endpoint is pain measured on a (0-10) Numeric Rating Scale 1 month after inclusion. Secondary outcomes include assessment of neuropathic pain, sleep, quality of life, anxiety/depression and cognitive function at 2 and 3 months. Data analysis is performed using mixed models and the tests are two-sided, with a type I error set at α=0.05. This study will explore if oral memantine and/or dextromethorphan may be a beneficial relay in ketamine responders and may diminish ketamine infusion frequency. Preservation of cognitive function and quality of life is also a central issue that will be analyzed in these vulnerable patients.
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Morel V, Pickering G, Etienne M, Dupuis A, Privat AM, Chalus M, Eschalier A, Daulhac L. Low doses of dextromethorphan have a beneficial effect in the treatment of neuropathic pain. Fundam Clin Pharmacol 2014; 28:671-80. [PMID: 24702319 DOI: 10.1111/fcp.12076] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Revised: 03/20/2014] [Accepted: 04/01/2014] [Indexed: 12/30/2022]
Abstract
N-methyl-D-aspartate receptor (NMDAR) antagonists may be given in persistent neuropathic pain, but adverse events especially with ketamine may limit their clinical use. Less central and cognitive adverse events are described with dextromethorphan and memantine. These molecules have been explored in many preclinical and clinical studies, but data are conflicting as regards neuropathic pain alleviation. Dextromethorphan and memantine have been administered to animals after spinal nerve ligation (SNL) to evaluate their antinociceptive/cognitive effects and associated molecular events, including the phosphorylation of several tyrosine (pTyr(1336), pTyr(1472)) residues in the NR2B NMDAR subunit. Spinal nerve ligation and sham animals received dextromethorphan (10 mg/kg, i.p.), memantine (20 mg/kg, i.p.) or saline (1 mL/kg, i.p.). These drugs were administered once symptoms of allodynia and hyperalgesia had developed. Tests were carried out before and after surgery. Tactile allodynia, mechanical hyperalgesia and spatial memory were, respectively, evaluated by von Frey, Randall & Selitto and Y-maze tests and molecular events by Western blot analysis. Spinal nerve-ligated animals displayed nociception and impaired spatial memory. Dextromethorphan, but not memantine, reversed neuropathic pain (NP) symptoms, restored spatial memory integrity and decreased the expression of pTyr(1336)NR2B. Following postoperative administration of dextromethorphan, this study has demonstrated for the first time a concordance between behaviour, cognitive function and molecular events via pTyr(1336)NR2B for neuropathic pain alleviation. Confirmation of these findings in patients would constitute a major step forward in the treatment of neuropathic pain and in the improvement of cognitive function and quality of life.
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Affiliation(s)
- Véronique Morel
- Facultés de Médecine/Pharmacie, Laboratoire de Pharmacologie, Clermont Université, Université d'Auvergne, Pharmacologie Fondamentale et Clinique de la Douleur, F-63000, Clermont-Ferrand, France; Inserm, U1107 Neuro-Dol, F-63001, Clermont-Ferrand, France; Centre de Pharmacologie Clinique, CHU Clermont-Ferrand, Inserm CIC 501, F-63003, Clermont-Ferrand, France
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Flor H. Maladaptive plasticity, memory for pain and phantom limb pain: review and suggestions for new therapies. Expert Rev Neurother 2014; 8:809-18. [DOI: 10.1586/14737175.8.5.809] [Citation(s) in RCA: 118] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Malavera Angarita MA, Carrillo Villa S, Gomezese Ribero OF, García RG, Silva Sieger FA. Pathophysiology and treatment of phantom limb pain. COLOMBIAN JOURNAL OF ANESTHESIOLOGY 2014. [DOI: 10.1016/j.rcae.2013.10.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Malavera Angarita MA, Carrillo Villa S, Gomezese Ribero OF, García RG, Silva Sieger FA. Fisiopatología y tratamiento del dolor de miembro fantasma. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.rca.2013.09.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Memantine, a promising drug for the prevention of neuropathic pain in rat. Eur J Pharmacol 2013; 721:382-90. [DOI: 10.1016/j.ejphar.2013.06.020] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 06/04/2013] [Accepted: 06/19/2013] [Indexed: 01/01/2023]
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McCormick Z, Chang-Chien G, Marshall B, Huang M, Harden RN. Phantom limb pain: a systematic neuroanatomical-based review of pharmacologic treatment. PAIN MEDICINE 2013; 15:292-305. [PMID: 24224475 DOI: 10.1111/pme.12283] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE Review the current evidence-based pharmacotherapy for phantom limb pain (PLP) in the context of the current understanding of the pathophysiology of this condition. DESIGN We conducted a systematic review of original research papers specifically investigating the pharmacologic treatment of PLP. Literature was sourced from PubMed, Embase, Scopus, and the Cochrane Central Register of Controlled Trials (CENTRAL). Studies with animals, "neuropathic" but not "phantom limb" pain, or without pain scores and/or functional measures as primary outcomes were excluded. A level of evidence 1-4 was ascribed to individual treatments. These levels included meta-analysis or systematic reviews (level 1), one or more well-powered randomized, controlled trials (level 2), retrospective studies, open-label trials, pilot studies (level 3), and anecdotes, case reports, or clinical experience (level 4). RESULTS We found level 2 evidence for gabapentin, both oral (PO) and intravenous (IV) morphine, tramadol, intramuscular (IM) botulinum toxin, IV and epidural Ketamine, level 3 evidence for amitriptyline, dextromethorphan, topiramate, IV calcitonin, PO memantine, continuous perineural catheter analgesia with ropivacaine, and level 4 evidence for methadone, intrathecal (IT) buprenorphine, IT and epidural fentanyl, duloxetine, fluoxetine, mirtazapine, clonazepam, milnacipran, capsaicin, and pregabalin. CONCLUSIONS Currently, the best evidence (level 2) exists for the use of IV ketamine and IV morphine for the short-term perioperative treatment of PLP and PO morphine for an intermediate to long-term treatment effect (8 weeks to 1 year). Level 2 evidence is mixed for the efficacy of perioperative epidural anesthesia with morphine and bupivacaine for short to long-term pain relief (perioperatively up to 1 year) as well as for the use of gabapentin for pain relief of intermediate duration (6 weeks).
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Affiliation(s)
- Zachary McCormick
- Department of Physical Medicine and Rehabilitation, The Rehabilitation Institute of Chicago/Northwestern McGaw Medical Center, Chicago, Illinois, USA
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Chaparro LE, Smith SA, Moore RA, Wiffen PJ, Gilron I. Pharmacotherapy for the prevention of chronic pain after surgery in adults. Cochrane Database Syst Rev 2013; 2013:CD008307. [PMID: 23881791 PMCID: PMC6481826 DOI: 10.1002/14651858.cd008307.pub2] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND Chronic pain can often occur after surgery, substantially impairing patients' health and quality of life. It is caused by complex mechanisms that are not yet well understood. The predictable nature of most surgical procedures has allowed for the conduct of randomized controlled trials of pharmacological interventions aimed at preventing chronic postsurgical pain. OBJECTIVES The primary objective was to evaluate the efficacy of systemic drugs for the prevention of chronic pain after surgery by examining the proportion of patients reporting pain three months or more after surgery. The secondary objective was to evaluate the safety of drugs administered for the prevention of chronic pain after surgery. SEARCH METHODS We identified randomized controlled trials (RCTs) of various systemically administered drugs for the prevention of chronic pain after surgery from CENTRAL, MEDLINE, EMBASE and handsearches of other reviews and trial registries. The most recent search was performed on 17 July 2013. SELECTION CRITERIA Included studies were double-blind, placebo-controlled, randomized trials involving adults and evaluating one or more drugs administered systemically before, during or after surgery, or both, which measured pain three months or more after surgery. DATA COLLECTION AND ANALYSIS Data collected from each study included the study drug name, dose, route, timing and duration of dosing; surgical procedure; proportion of patients reporting any pain three months or more after surgery, reporting at least 4/10 or moderate to severe pain three months or more after surgery; and proportion of participants dropping out of the study due to treatment-emergent adverse effects. MAIN RESULTS We identified 40 RCTs of various pharmacological interventions including intravenous ketamine (14 RCTs), oral gabapentin (10 RCTs), oral pregabalin (5 RCTs), non-steroidal anti-inflammatories (3 RCTs), intravenous steroids (3 RCTs), oral N-methyl-D-aspartate (NMDA) blockers (3 RCTs), oral mexiletine (2 RCTs), intravenous fentanyl (1 RCT), intravenous lidocaine (1 RCT), oral venlafaxine (1 RCT) and inhaled nitrous oxide (1 RCT). Meta-analysis suggested a modest but statistically significant reduction in the incidence of chronic pain after surgery following treatment with ketamine but not gabapentin or pregabalin. Results with ketamine should be viewed with caution since most of the included trials were small (that is < 100 participants per treatment arm), which could lead to the overestimation of treatment effect. AUTHORS' CONCLUSIONS Additional evidence from better, well designed, large-scale trials is needed in order to more rigorously evaluate pharmacological interventions for the prevention of chronic pain after surgery. Furthermore, available evidence does not support the efficacy of gabapentin, pregabalin, non-steroidal anti-inflammatories, intravenous steroids, oral NMDA blockers, oral mexiletine, intravenous fentanyl, intravenous lidocaine, oral venlafaxine or inhaled nitrous oxide for the prevention of chronic postoperative pain.
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Abstract
Postamputation pain (PAP) is highly prevalent after limb amputation but remains an extremely challenging pain condition to treat. A large part of its intractability stems from the myriad pathophysiological mechanisms. A state-of-art understanding of the pathophysiologic basis underlying postamputation phenomena can be broadly categorized in terms of supraspinal, spinal, and peripheral mechanisms. Supraspinal mechanisms involve somatosensory cortical reorganization of the area representing the deafferentated limb and are predominant in phantom limb pain and phantom sensations. Spinal reorganization in the dorsal horn occurs after deafferentataion from a peripheral nerve injury. Peripherally, axonal nerve damage initiates inflammation, regenerative sprouting, and increased "ectopic" afferent input which is thought by many to be the predominant mechanism involved in residual limb pain or neuroma pain, but may also contribute to phantom phenomena. To optimize treatment outcomes, therapy should be individually tailored and mechanism based. Treatment modalities include injection therapy, pharmacotherapy, complementary and alternative therapy, surgical therapy, and interventions aimed at prevention. Unfortunately, there is a lack of high quality clinical trials to support most of these treatments. Most of the randomized controlled trials in PAP have evaluated medications, with a trend for short-term Efficacy noted for ketamine and opioids. Evidence for peripheral injection therapy with botulinum toxin and pulsed radiofrequency for residual limb pain is limited to very small trials and case series. Mirror therapy is a safe and cost-effective alternative treatment modality for PAP. Neuromodulation using implanted motor cortex stimulation has shown a trend toward effectiveness for refractory phantom limb pain, though the evidence is largely anecdotal. Studies that aim to prevent PA P using epidural and perineural catheters have yielded inconsistent results, though there may be some benefit for epidural prevention when the infusions are started more than 24 hours preoperatively and compared with nonoptimized alternatives. Further investigation into the mechanisms responsible for and the factors associated with the development of PAP is needed to provide an evidence-based foundation to guide current and future treatment approaches.
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Affiliation(s)
- Eugene Hsu
- Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Steven P Cohen
- Johns Hopkins School of Medicine and Uniformed Services, University of the Health Sciences, Bethesda, MD, USA
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48
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Cepeda MS, Berlin JA, Gao CY, Wiegand F, Wada DR. Placebo Response Changes Depending on the Neuropathic Pain Syndrome: Results of a Systematic Review and Meta-Analysis. PAIN MEDICINE 2012; 13:575-95. [DOI: 10.1111/j.1526-4637.2012.01340.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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49
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McGreevy K, Bottros MM, Raja SN. Preventing Chronic Pain following Acute Pain: Risk Factors, Preventive Strategies, and their Efficacy. ACTA ACUST UNITED AC 2012; 5:365-372. [PMID: 22102847 DOI: 10.1016/j.eujps.2011.08.013] [Citation(s) in RCA: 138] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Chronic pain is the leading cause of disability in the United States. The transition from acute to persistent pain is thought to arise from maladaptive neuroplastic mechanisms involving three intertwined processes, peripheral sensitization, central sensitization, and descending modulation. Strategies aimed at preventing persistent pain may target such processes. Models for studying preventive strategies include persistent post-surgical pain (PPP), persistent post-trauma pain (PTP) and post-herpetic neuralgia (PHN). Such entities allow a more defined acute onset of tissue injury after which study of the long-term effects is more easily examined. In this review, we examine the pathophysiology, epidemiology, risk factors, and treatment strategies for the prevention of chronic pain using these models. Both pharmacological and interventional approaches are described, as well as a discussion of preventive strategies on the horizon.
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Affiliation(s)
- Kai McGreevy
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
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50
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Schley M, Topfner S, Wiech K, Schaller HE, Konrad CJ, Schmelz M, Birbaumer N. Continuous brachial plexus blockade in combination with the NMDA receptor antagonist memantine prevents phantom pain in acute traumatic upper limb amputees. Eur J Pain 2012; 11:299-308. [PMID: 16716615 DOI: 10.1016/j.ejpain.2006.03.003] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2005] [Revised: 03/26/2006] [Accepted: 03/28/2006] [Indexed: 11/21/2022]
Abstract
BACKGROUND Hyperexcitability of N-methyl-d-aspartate acid (NMDA) receptors may play an important role in the development of phantom limb pain (PLP). AIM OF THE STUDY To investigate whether early treatment with the NMDA antagonist memantine attenuates phantom pain memory formation in traumatic amputees. METHODS In a randomized, double-blind, controlled trial 19 patients with acute traumatic amputation of the upper extremity were investigated. All patients received postoperative analgesia by continuous brachial plexus anesthesia (ropivacaine 0.375% 5 ml/h) for at least 7 days. In addition, the patients received either memantine (20-30 mg daily, n=10) or placebo (n=9) for 4 weeks. RESULTS Memantine treatment reduced the number of requested ropivacacine bolus injections during the first week and resulted in a significant decrease of PLP prevalence and intensity at 4 weeks and 6 months follow up, but not at 12 months follow up. CONCLUSIONS We conclude that memantine can reduce intensity of phantom limb pain and might also prevent the development of PLP. However, despite the very early begin of treatment; no long-term effect on established PLP was evident.
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Affiliation(s)
- M Schley
- Department of Anaesthesiology and Intensive Care Medicine, Experimental Pain Research/Pain Centre, University of Heidelberg, Faculty of Clinical Medicine, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany.
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