Study of Long Term Effects of Laser Therapy Versus Local Corticosteroid Injection in Patients with Carpal Tunnel Syndrome

Abstract INTRODUCTION: Carpal Tunnel Syndrome (CTS) is the most common compressive neuropathy. Several surgical and nonsurgical treatments have been proposed for this syndrome, but there is no consensus regarding the prioritization of the suggested nonsurgical treatments. The goal of this study was to compare the long term effects of laser therapy versus local corticosteroid injection in the treatment of CTS.METHODS:During this single-blind randomized clinical trial, ۶۵ hands with mild or moderate CTS were divided randomly into two groups. One group received local corticosteroid injection (Hydrocortisone ۵۰ mg) and the other received low level laser therapy (۲۰J/cm² in ۱۱ seconds/session for each of ۵ points, ۷۷۵nm, ۱۰ sessions and ۳sessions/week). Furthermore, wrist splints with extension degree of ۰° (neutral position) were prescribed simultaneously for ۶ weeks in each group.Pain severity and electrodiagnostic measurements were compared from before to ۱۰ months after completing each treatment. Data were analyzed with SPSS ۱۱.۵ software and parametric tests.RESULTS: Generally, the mean age of patients was ۴۳.۹ years, duration of pain was ۷.۴ months, male to female ratio was ۱:۳, pain severity using Visual Analogue Scale (VAS) was ۶.۱ cm, and functional status measure was ۱۵.۵. The severity of the disease based on electrodiagnostic studies was ۴۳.۲% mild (۴۱.۲% in injection group and ۴۵.۲% in laser therapy group) and ۵۶.۸% moderate. The electrodiagnostic characteristics of the median nerve prior to treatment were included mean sensory peak latency of ۴.۳ms, mean sensory amplitude of ۲۳.۵μv, mean motor onset latency of ۴.۳ms and mean motor amplitude of ۴.۶mv. There was no meaningful difference between two groups regarding the demographic characteristics and electrodiagnostic measures (p>۰.۰۵). Ten months after treatments, the mean of pain severity was decreased ۱.۹cm in injection group and ۱.۷cm in laser therapy group, the mean of median sensory peak latencies was decreased ۰.۴ms in injection group and ۰.۲۵ms in laser therapy group and the mean of motor onset latencies was decreased ۰.۱۵ms in both groups,with no significant difference between the observed treatments variables (P>۰.۰۵). The severity of disease based on electrodiagnostic studies became ۳۲.۴% normal,۲۳.۵% mild, ۴۱.۲% moderate and ۲.۹% severe in the injection group and ۳۸.۷% normal,۲۲.۶% mild, ۳۵.۵% moderate and ۳.۲% severe in the laser therapy group. There was no meaningful difference between two groups regarding the changes in the pain severity, functional status and electrodiagnostic measures.CONCLUSION: Low level laser therapy can be as effective as local injection in reducing pain and severity of disease (based on electrodiagnostic medicine classification) in patients with mild and moderate CTS even in long term (after ۱۰ months). Keywords: Carpal Tunnel Syndrome Laser therapy Corticosteroids Electrodiagnosis