Incidence, Timing, and Predictors of Staged Contralateral Carpal Tunnel Release at Minimum Ten-Year Follow-Up from Unilateral Surgery.

Abstract

Carpal tunnel syndrome is one of the most prevalent upper-extremity disorders. It may present unilaterally, bilaterally, or on the contralateral hand at a subsequent time to initial carpal tunnel release (CTR). We aimed to assess the incidence, timing, and factors associated with contralateral CTR at the time of an index unilateral surgery. We performed a retrospective chart review of 1,291 primary unilateral CTR surgeries performed from 2008 to 2013 with a minimum follow-up period of 10 years within our integrated health network. In total, 742 (58%) patients met our inclusion criteria. We conducted bivariate analyses to assess for risk factors associated with contralateral CTR. Odds ratios were calculated for variables with significant results. A Kaplan-Meier curve was generated to depict the overall cumulative rate of contralateral CTR-free survival. Of the 742 patients included, 314 patients (42%) underwent contralateral CTR surgery at a median of 10.6 months (IQR 4.2 months to 2.7 years) after primary surgery. The incidence of contralateral CTR after 1, 2, 5, and 10 years is 22%, 26%, 34%, and 40%, respectively. The strongest predictor was the presence of contralateral carpal tunnel syndrome symptoms at the time of index surgery (odds ratio [OR] 7.2, P < .05). Other significant risk factors included preoperative contralateral electrodiagnostic study severity (OR 1.43 per unit increase, P < .001) and a concurrent diagnosis of trigger finger (OR 1.80, P < .05). Black race was associated with significantly lower odds of contralateral surgery (OR 0.44, P < .05). The incidence of contralateral CTR surgery is substantial over long-term follow-up. The observed association among trigger finger, Black race, and contralateral CTR warrants further research. Our findings help to inform preoperative counseling for patients undergoing unilateral CTR. Prognostic III.