Comparison of surgical decompression and local steroid injection in the treatment of carpal tunnel syndrome: 2-year clinical results from a randomized trial.

OBJECTIVE To compare the efficacy of surgical decompression vs local steroid injection in the treatment of idiopathic CTS. METHODS This is an open, prospective, randomized clinical trial. We studied the effects of surgical decompression vs local steroid injection in 163 wrists with a clinical diagnosis and neurophysiological confirmation of CTS, with an extended follow-up of 2 years. The primary end point was the percentage of wrists that reached a ≥ 20% improvement in the visual analogue scale score for nocturnal paraesthesias. Statistical analysis was done by Student's t-test for continuous variables and by chi-square test for categorical variables. Analyses were performed on an intent-to-treat basis. P < 0.05 were considered statistically significant. RESULTS Both treatment groups had comparable severity of CTS at baseline. Eighty wrists were randomly assigned to surgical decompression and 83 wrists to local steroid injection. Fifty-five wrists in the surgery group and 48 wrists in the injection group completed the 2-year follow-up. In the intent-to-treat analysis, at 2-year follow-up, 60% of the wrists in the injection group vs 69% in the surgery group reached a 20% response for nocturnal paraesthesias (P < 0.001). CONCLUSION Our findings suggest that both local steroid injection and surgical decompression are effective treatments in alleviating symptoms in primary CTS at 2-year follow-up. Surgery has an additional benefit in the 2-year follow-up, although clinical relevance of those differences remains to be defined. TRIAL REGISTRATION Current Controlled Trials, www.controlled-trials.com, ISRCTN26264638.