The Role of Exercise in the Alleviation of Neuropathic Pain Following Traumatic Spinal Cord Injuries: A Systematic Review and Meta-analysis

Abstract

Objective: The objective of this systematic review and meta-analysis was to assess the efficacy of exercise in neuropathic pain following traumatic spinal cord injuries.Methods: The search was conducted in MEDLINE, Embase, Scopus, and Web of Science by the end of 2022. Two independent researchers included the articles based on the inclusion and exclusion criteria. A standardized mean difference was calculated for each data and they were pooled to calculate an overall effect size. To assess the heterogeneity between studies, I<sup>2</sup> and chi-square tests were utilized. In the case of heterogeneity, meta-regression was performed to identify the potential source.Results: Fifteen preclinical studies were included. Meta-analysis demonstrated that exercise significantly improves mechanical allodynia (standardized mean difference [SMD], -1.59; 95% confidence interval [CI], -2.16 to -1.02; p < 0.001; I<sup>2</sup> = 90.37%), thermal hyperalgesia (SMD, 1.95; 95% CI, 0.96–2.94; p < 0.001), and cold allodynia (SMD, -2.92; 95% CI, -4.4 to -1.43; p < 0.001). The improvement in mechanical allodynia is significantly more in animals with a compression model of SCI (meta-regression coefficient, -1.33; 95% CI, -1.84 to -0.57; p < 0.001) and in mild SCI (p < 0.001). Additionally, the improvement was more prominent if the training was started 7 to 8 days postinjury (coefficient, -2.54; 95% CI, -3.85 to -1.23; p < 0.001) and was continued every day (coefficient, -1.99; 95% CI, -3.07 to -0.9; p < 0.001). Likewise, voluntary exercise demonstrated a significantly more effect size (coefficient, -1.45; 95% CI, -2.67 to -0.23; p = 0.02).Conclusion: Exercise is effective in the amelioration of neuropathic pain. This effect in mechanical allodynia is more prominent if voluntary, continuous training is initiated in the subacute phase of mild SCI.

A Narrative Review of the Dorsal Root Ganglia and Spinal Cord Mechanisms of Action of Neuromodulation Therapies in Neuropathic Pain

“…In general, studies will differentiate between aerobic and anaerobic exercises, and how each type of muscle contraction acts on pain. We suggest some review articles on this topic [40,41,[97][98][99][100]. [87,88].…”

“…In general, studies will differentiate between aerobic and anaerobic exercises, and how each type of muscle contraction acts on pain. We suggest some review articles on this topic [40,41,[97][98][99][100]. Current pharmacological approaches consist of the medical prescription of seven main classes of drugs: (1) serotonin-and noradrenaline modulating antidepressants, (2) sodiumblocking anticonvulsants, (3) calcium-modulating anticonvulsants, (4) tramadol, (5) opioids, (6) capsaicin, and (7) local anesthetics [79].…”

Therapeutic potential of luteolin-loaded poly(lactic-co-glycolic acid)/modified magnesium hydroxide microsphere in functional thermosensitive hydrogel for treating neuropathic pain

“… 1 , 2 Globally, approximately 7%–10% of the population endures NP, leading to significant physical and psychological distress. 3 , 4 The primary pathological mechanisms of NP mainly involve central and peripheral nerve sensitization, inflammation, oxidative stress, and release of pro-inflammatory cytokines. 5 – 8 Activated microglia and macrophages contribute to the production of interleukins and tumor necrosis factor-alpha (TNF-α), culminating in inflammation and cellular apoptosis.…”