Surgical decompression versus local steroid injection in carpal tunnel syndrome: a one-year, prospective, randomized, open, controlled clinical trial.

Objective: Optimal treatment of carpal tunnel syndrome (CTS) has not been established. This study compared the effects of local steroid injection versus surgical decompression in new-onset CTS of at least 3 months' duration.

Methods: In a 1-year, prospective, randomized, open, controlled clinical trial, we studied the effects of surgical decompression versus local steroid injection in 163 wrists with a clinical and neurophysiologic diagnosis of CTS. Clinical assessments were done at baseline and at 3, 6, and 12 months after treatment. The primary end point was the percentage of wrists that reached a >or=20% improvement in the visual analog scale score for nocturnal paresthesias at 3 months of followup. 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 values less than 0.05 were considered statistically significant.

Results: Both treatment groups had comparable severity of CTS at baseline. Eighty wrists were randomly assigned to the surgery group and 83 wrists to the local steroid injection group. In the intent-to-treat analysis, at 3 months of followup, 94.0% of the wrists in the steroid injection group versus 75.0% in the surgery group reached a 20% response for nocturnal paresthesias (P = 0.001). At 6 and 12 months, the percentages of responders were 85.5% versus 76.3% (P = 0.163) and 69.9% versus 75.0% (P = 0.488), for local steroid injection and surgical decompression, respectively.

Conclusion: Over the short term, local steroid injection is better than surgical decompression for the symptomatic relief of CTS. At 1 year, local steroid injection is as effective as surgical decompression for the symptomatic relief of CTS.