Opponensplasty for Severe Carpal Tunnel Syndrome with the Transfer of the Palmaris Longus Tendon to the Rerouted Extensor Pollicis Brevis Tendon.

The authors describe a novel opponensplasty for severe carpal tunnel syndrome that uses the palmaris longus (PL) tendon transferred to the rerouted extensor pollicis brevis (EPB) tendon with pulley reconstruction using a portion of the PL tendon simultaneously with the carpal tunnel release. Like the Camitz opponensplasty, this technique utilises the PL as the motor source, does not require special postoperative treatment and enables fast functional recovery even in older patients. Compared with the Camitz procedure, this technique can easily acquire thumb rotation without tendon bowstringing. Furthermore, because the function of the EPB tendon is preserved, the tendency of flexion in the thumb metacarpophalangeal (MP) joint is not observed after surgery, and improvement can be expected in patients with preoperative MP joint extension lag. This technique is a useful alternative to the Camitz procedure, as it overcomes the disadvantages of the Camitz procedure while preserving the advantages. Level of Evidence: Level V (Therapeutic).