Long-term outcome after carpal tunnel release and identification of prognostic factors.

Background: The effectiveness of the surgical treatment of carpal tunnel syndrome (CTS) is well known on short term. However, limited data is available about long-term outcome after carpal tunnel release (CTR). The aims of this study were to explore the long-term outcome after CTR and to identify prognostic factors for long-term outcome.

Methods: Patients with clinically defined CTS underwent CTR and completed the Boston Carpal Tunnel Questionnaire at baseline (T), at about 8 months (T), and after a median follow-up of 9 years (T), as well as a 6-point scale for perceived improvement (at T and T). Potentially prognostic factors were identified by logistic regression analysis and correlation.

Results: At long-term follow-up, 87 patients (40.3%) completed the questionnaires. Mean score on Symptom Severity Scale (2.87 to 1.54; p < 0.001) and Functional Status Scale (2.14 to 1.51; p < 0.001) improved at 8 months and did not change significantly after 8 months. A favorable outcome was reported in 81.6%. A good treatment outcome after 8 months and to a lesser extent a lower FSS score at T were associated with a better long-term outcome.

Conclusions: CTR is a robust treatment for CTS and its effect persists after a period of 9 years. The most important factor associated with long-term outcome is treatment outcome after about 8 months and to a lesser extent functional complaints preoperatively. Outcome is independent of patient characteristics, electrodiagnostic test results, or findings at the initial neurological examination.