Prospective Evaluation of a Single Corticosteroid Injection in Radial Tunnel Syndrome

Background: The role of corticosteroid injections in the treatment of radial tunnel syndrome (RTS) has not been evaluated in depth. The purpose of this study was to evaluate the utility of a single corticosteroid injection as a therapeutic modality for RTS. Methods: We enrolled 40 patients with a clinical diagnosis of RTS. Our primary outcome was the quick Disabilities of the Arm, Shoulder and Hand (qDASH) score at 1 year. Each patient was then treated with a single corticosteroid injection in the proximal forearm at the posterior interosseous nerve (PIN). Patient follow-up occurred at 2 weeks, 3 months, and 1 year. Results: The cohort had a mean age of 49 years, and 35 patients completed 1 year of follow-up. Outcomes based on qDASH and visual analog scale (VAS) showed significant improvement from baseline, with mean qDASH decreasing from 49.4 ± 7.0 points to 35.8 ± 7.5 points (P = .03) and 28.5 ± 7.3 points (P = .01) at 12 and 52 weeks, respectively, and VAS decreasing from 6.0 ± 0.8 points to 3.4 ± 0.9 points (P = .005) and 2.9 ± 0.8 points (P = .003) at 12 and 52 weeks, respectively. During the study period, 8 of 35 patients (23%) failed nonoperative treatment and went on to surgical decompression of the PIN. A minimal clinically important difference in qDASH was achieved in 57% of subjects at 1-year follow-up. Conclusions: Nonoperative management with corticosteroid injection can be used as a therapeutic measure with potential long-term benefits in the treatment of RTS.