Central Nervous System Reorganization and Pain After Spinal Cord Injury: Possible Targets for Physical Therapy—A Systematic Review of Neuroimaging Studies

Abstract

Background Pain is one of the main symptoms associated with spinal cord injury (SCI) and can be associated with changes to the central nervous system (CNS). Purpose This article provides an overview of the evidence relating to CNS changes (structural and functional) associated with pain in SCIs. Data Sources A systematic review was performed, according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations, on PubMed, Embase, and Web of Science in March 2018. Study Selection Studies were selected if they concerned changes in the CNS of patients with SCI, regardless of the type of imagery. Data Extraction Data were extracted by 2 blinded reviewers. Data Synthesis There is moderate evidence for impaired electroencephalographic function and metabolic abnormalities in the anterior cingulate in patients experiencing pain. There is preliminary evidence that patients with pain have morphological and functional changes to the somatosensory cortex and alterations to thalamic metabolism. There are conflicting data regarding the relationships between lesion characteristics and pain. In contrast, patients without pain can display protective neuroplasticity. Limitations and Conclusion Further studies are required to elucidate fully the relationships between pain and neuroplasticity in patients with SCIs. However, current evidence might support the use of physical therapist treatments targeting CNS plasticity in patients with SCI pain.

Altered bodily perceptions in chronic neuropathic pain conditions and implications for treatment using immersive virtual reality

“…It is thought that ongoing activity in residual spinothalamic pathways plays a key role in the maintenance of central pain in SCI (Wasner et al, 2008 ). In addition, the reorganization of the somatosensory systems and changes in body representations related to the massive deafferentation associated with SCI (Jutzeler et al, 2015 ; Osinski et al, 2020 ; Vastano et al, 2022 ) are thought to play a role in both the development of pain and perceptual alterations, although the degree to which the cortex reorganizes is highly variable (Moxon et al, 2014 ). Vastano et al ( 2022 ) provide a comprehensive overview of cortical changes following SCI, their associated perceptual alterations, and the use of multisensory bodily illusions to induce pain relief.…”

Identifying Body Awareness-Related Brain Network Changes after Cognitive Multisensory Rehabilitation for Neuropathic Pain Relief in Adults with Spinal Cord Injury: Delayed Treatment arm Phase I Randomized Controlled Trial

“…30,40–43 However, there is a lack of consensus as to which brain regions and networks are involved in pain in this heterogeneous population. 30,31,36–39 Nevertheless, there is strong evidence that the parietal operculum (secondary somatosensory cortex, parts OP1/OP4) and the neighboring insula, also called the parieto-insular cortex, are key areas for both body awareness and pain processing. 6,30,32,44–55…”

Interplay between body schema, visuospatial perception and pain in patients with spinal cord injury

“…More than half of the patients with spinal cord injury (SCI) suffer chronic neuropathic pain syndromes (Burke, Fullen, Stokes, & Lennon, 2017; Siddall & Middleton, 2015). The mechanisms of neuropathic pain, particularly for below‐level pain, remain poorly understood, but may involve the reorganization of the somatosensory systems and changes in body representations related to the massive deafferentation associated with SCI (Jutzeler, Curt, & Kramer, 2015; Osinski, Acapo, Bensmail, Bouhassira, & Martinez, 2019).…”

“…It is difficult to speculate about the brain mechanisms underlying the interplay between pain and LJT in SCI patients. Structural, functional and neurochemical central changes have been reported in these patients (Gustin, Wrigley, Siddall, & Henderson, 2010;Gustin et al, 2014;Hatem et al, 2010;Henderson, Gustin, Macey, Wrigley, & Siddall, 2011;Jutzeler et al, 2015;Nardone et al, 2013;Osinski et al, 2019), but the relationships between brain changes and LJT or between LJT and pain have never been studied directly in patients.…”