Effectiveness of an Endoscopic Recurrent Branch Release Procedure Combined with Standard Endoscopic Carpal Tunnel Release Surgery Compared to Standard Endoscopic Carpal Tunnel Release Surgery Alone: A Propensity Score-Matched Study

Background: The purpose of this study is to compare the effectiveness of endoscopic release of the recurrent branch from surrounding soft tissue in combination with standard endoscopic carpal tunnel release (ECTR) surgery to standard ECTR surgery alone in patients with established abductor pollicis brevis (APB) muscle weakness. Methods: Using propensity score matching, we compared the recovery rates of postoperative clinical symptoms in patients with idiopathic carpal tunnel syndrome in whom the preoperative Medical Research Council (MRC) scale of the APB muscle (MRC-APB) was zero (no contraction) and with undetectable distal motor latency (DML) of APB, to those who underwent standard ECTR surgery alone and those who underwent recurrent branch release in addition to standard ECTR. Results: Forty-nine hands in the recurrent branch release group and 49 hands in the standard ECTR surgery group were extracted. There were statistically significant differences in postoperative recovery rate from MRC-APB 0 to ‘4 or 5’ at 30 months (OR: 2.42; 95% CI: 1.03–5.67; p = 0.04) and at final follow-up (OR: 2.64; 95% CI: 1.11–6.26; p = 0.03). There were statistically significant differences in postoperative recovery of MRC-APB scales at 24 months (p = 0.03), 30 months (p = 0.02) and at final follow-up (p = 0.02). There were statistically significant differences in postoperative recovery of DML (p = 0.04). Conclusions: Endoscopic release of the recurrent branch in combination with standard ECTR surgery showed better recovery rates in MRC-APB and DML recovery compared to standard ECTR surgery alone. Level of Evidence: Level III (Therapeutic)