Noninvasive neuromodulation for the management of phantom limb pain: A systematic review

Abstract

Maladaptive plastic reorganization of the somatosensory cortex surrounding the area representing the deafferented limb is considered to be responsible for phantom limb pain (PLP). Given the mechanism of PLP, noninvasive stimulation of the brain can help to induce plastic changes associated with PLP, which may in turn block maladaptive plasticity, revert or modulate plastic changes and provide pain relief. This review aims to give an overview of the current state of research regarding the effectiveness of noninvasive neuromodulation for the management of PLP. A systematic literature search in the PUBMED, SCOPUS, Web of Science, Cochrane Library databases by two independent review authors was performed to identify studies investigating the effects of noninvasive neuromodulation for PLP. The included journal articles were reviewed according to a structured diagram and the methodological quality was assessed via a classification of study designs as described by Jovell & Navarro-Rubio. A narrative synthesis approach was used throughout as no studies were sufficiently homogenous to justify useful meta-analysis. The literature search identified 239 studies. Of these 239, 4 RCTs studies fulfilled the inclusion criteria and were included for data extraction. Two of the studies focused on repetitive transcranial magnetic stimulation (rTMS) while two of them focused on transcranial direct current stimulation (tDCS). Most of the evidence for noninvasive neuromodulation is from studies with fair to good strength of evidence. The present review showed that there is promising evidence on the effectiveness of rTMS for PLP, whereas the effectiveness of tDCS is not yet elucidated. CRD42017075454.