Interventions for treating the radial tunnel syndrome: a systematic review of observational studies.

PURPOSE For some disorders, such as radial tunnel syndrome (RTS), no randomized controlled trials and controlled clinical trials are available. To gain insight into the effectiveness of conservative and surgical interventions for treating RTS, we systematically reviewed all available observational studies on treatment of RTS. Although the validity of case series is inferior to that of controlled trials, the case series might provide valuable data about the efficacy of treatment options. METHODS A literature search and additional reference checking resulted in 21 eligible case series for this review. Based on previous checklists, we constructed a new quality assessment and rating system to analyze the included case series. The methodological quality was assessed, and data extraction was performed. Studies with less than 50% of the maximum points on the methodological quality assessment were considered inadequate and were excluded from the analysis. To summarize the results according to the rating system for the strength of the scientific evidence for these case series, we introduced 4 levels: (1) tendency, (2) slight tendency, (3) conflicting tendency, and (4) no tendency. RESULTS After the methodological quality assessment, 6 articles were included in the final analysis. They all reported on surgical treatment. CONCLUSIONS There is a tendency that surgical decompression of the radial tunnel might be effective in patients with RTS. The effectiveness of conservative treatments for RTS is unknown because, for most treatments, no studies were available. Additional high-quality controlled studies are needed to assess the level of conclusive evidence for surgical treatment and also to evaluate conservative treatments for RTS. For this, we recommend a multicenter, randomized clinical trial. Due to the lack of a clear protocol for diagnosing RTS, a reliable and valid diagnostic tool should be developed. TYPE OF STUDY/LEVEL OF EVIDENCE Therapeutic IV.