Accessory extensor pollicis longus tendon in emergency surgery

A true accessory extensor tendon of the thumb seems to be rare. We found a variation of the accessory extensor pollicis longus (EPL) tendon while performing an emergency surgical procedure. Identification of this accessory tendon during emergency surgery has not been previously reported.Case presentation: A 43-year-old man presented to our hospital after sustaining a work-related injury involving a saw. During the operation, the tendons of the EPL, accessory EPL, and extensor pollicis brevis were severed. The lacerated tendon and tendon sheath were repaired, and the wrist and thumb were positioned in extension. The patient's postoperative activity returned to normal without the need for a second tendon release operation.

Surgeons should be aware of this anatomic anomaly of the EPL tendon. Presentation of our case increases clinicians' chances of preoperatively detecting this anomaly, which can improve surgical outcomes.