Effectiveness of focused extracorporeal shock wave therapy in the treatment of carpal tunnel syndrome: A randomized, placebo-controlled pilot study

BACKGROUND: The carpal tunnel syndrome is the most common entrapment neuropathy in the general population. A conservative treatment should be considered in mild to moderate cases. The aim of this study was to assess the effect of a focused extracorporeal shock wave therapy in the treatment of mild to moderate carpal tunnel syndrome. MATERIAL AND METHODS: In this study 30 patients were randomly assigned into 2 groups. Subjects in the study group received three sessions of focused extracorporeal shock wave therapy, whereas the control group underwent a sham therapy. Patients were evaluated 3 and 12 weeks after treatment. The primary outcome was the visual analogue scale score. Secondary outcome measurements included hand grip strength, Boston Carpal Tunnel Syndrome Questionnaire, SF-36 Health Survey and electrodiagnostic measurements. RESULTS: A significant improvement of visual analogue scale at week 3 (p = 0.018) and week 12 (p = 0.007) as well as hand grip strength at week 12 (p = 0.019) could be observed in the study group. The study group showed a significantly better sensory nerve conduction velocity at week 12 than the control group, before correcting for multiple testing, and also a significant improvement in distal motor latency of the median nerve at week 12 (p = 0.009) as well as in both questionnaires (SF-36 subscale bodily pain, p = 0.020 and severity symptom scale, p = 0.003). No such improvement was observed in the control group. CONCLUSION: Focused extracorporeal shock wave therapy is an effective and noninvasive treatment method for mild to moderate carpal tunnel syndrome.