Influence of sensory retraining on cortical reorganization in peripheral neuropathy: A systematic review.

Objective: This study systematically reviewed the literature about sensory retraining effect in comparison to other rehabilitative techniques on cortical reorganization in patients with peripheral neuropathic pain. TYPE: Systematic review.

Literature survey: After an electronic search of PubMed, Web of Science, and Embase, risk of bias was assessed using the revised Cochrane risk of bias tool for randomized controlled trials and the ROBINS-1 (Risk of bias in non-randomized studies-of interventions) for non-randomized studies of intervention.

Methodology: The strength of conclusion was determined using the evidence-based guideline development approach.

Synthesis: Limited evidence indicates a higher increase in cortical inhibition and a higher reduction in cortical activation during a motor task of the affected hemisphere after graded motor imagery compared to wait-list. Higher reductions in map volume (total excitability of the cortical representation) of the affected hemisphere after peripheral electrical stimulation (PES) were observed when compared to transcranial direct current stimulation (tDCS) or to sham treatment with limited evidence. No other differences in cortical excitability and representation of the affected and non-affected hemisphere were observed when comparing mirror therapy with sham therapy or tDCS, PES with sham therapy or tDCS, and graded motor imagery with wait-list.

Conclusions: Graded motor imagery and PES result in higher cortical excitability reductions of the affected hemisphere compared to wait-list, tDCS and sham treatment, respectively.