Recurrent and persistent carpal tunnel syndrome: predicting clinical outcome of revision surgery.

Objective: The aim of this study was to evaluate the self-reported outcome of revision surgery in patients with recurrent and persistent carpal tunnel syndrome (CTS) and to identify predictors of clinical outcome of revision surgery.

Methods: A total of 114 hands in 112 patients were surgically treated for recurrent and persistent CTS in one of 10 specialized hand clinics. As part of routine care, patients were asked to complete online questionnaires regarding demographic data, comorbidities, and clinical severity measures. The Boston Carpal Tunnel Questionnaire (BCTQ) was administered at intake and at 6 months postoperatively to evaluate clinical outcome. The BCTQ comprises the subscales Symptom Severity Scale (SSS) and Functional Status Scale (FSS), and the individual scores were also assessed. Using multivariable regression models, the authors identified factors predictive of the outcome as measured by the BCTQ FSS, SSS, and total score at 6 months.

Results: Revision surgery significantly improved symptoms and function. Longer total duration of symptoms, a higher BCTQ total score at intake, and diagnosis of complex regional pain syndrome (CRPS) along with CTS were associated with worse outcome after revision surgery at 6 months postoperatively. The multivariable prediction models could explain 33%, 23%, and 30% of the variance in outcome as measured by the FSS, SSS, and BCTQ total scores, respectively, at 6 months. Although patients with higher BCTQ scores at intake have worse outcomes, they generally have the most improvement in symptoms and function.

Conclusions: This study identified total duration of symptoms, BCTQ total score at intake, and diagnosis of CRPS along with CTS as predictors of clinical outcome and confirmed that revision surgery significantly improves self-reported symptoms and function in patients with recurrent and persistent CTS. Patients with more severe CTS symptoms have greater improvement in symptoms at 6 months postoperatively than patients with less severe CTS, but 80% of patients still had residual symptoms 6 months postoperatively. These results can be used to inform both patient and surgeon to manage expectations on improvement of symptoms.