Coincidence or complication? A systematic review of trigger digit after carpal tunnel release.

Background: Carpal tunnel syndrome (CTS) and trigger digits are among the most common nontraumatic hand disorders treated by plastic surgeons. The onset of trigger digits after carpal tunnel release (CTR) has been inconsistently reported. This systematic review assessed the prevalence of trigger digits development in patients after CTR surgery.

Methods: We searched the MEDLINE, EMBASE and SCOPUS databases for papers published between January 1966 and August 2016. Eligible studies contained quantitative data on the incidence of trigger digits after CTR. The primary outcome measure was the onset of trigger digits after CTR. The secondary outcome measure was the prevalence of digital involvement in patients who developed trigger digits after CTR.

Results: A total of 5654 CTR surgeries were performed in the included nine studies, and 483 patients (8.5%) developed trigger digits after CTR. The reported incidence of trigger digits after CTR ranged from 5.2% to 31.7%. The time to development of trigger digits was approximately 6 months postoperatively. In the eight observational studies and in the randomized controlled trial, the thumb and ring finger were reported as the most commonly involved trigger digits, respectively.

Conclusions: The incidence of trigger digits after CTR surgery is not negligible. Thumbs and ring fingers are the most commonly involved digits. This topic should therefore be suitably addressed during preoperative consultations.