Lunate Dislocation with Flexor Pollicis Longus Avulsion, and Thumb Collateral Ligament Injury: A Case Report

Lunate dislocation is a rare and devastating injury of the wrist that requires prompt management and surgical repair. The association of this lesion with a flexor pollicis longus (FPL) injury and a Stener lesion appears to be extremely uncommon.

We present the case of a 31-year-old man who was riding his motorbike when he was struck by a car, resulting in a volar dislocation of the lunate, a concomitant fracture of the second phalanx of the thumb, a FPL avulsion, and a thumb ulnar collateral ligament (UCL) injury. While there are numerous articles about associated lunate and other carpal and wrist injuries, a combination of lunate dislocation with the above-mentioned injuries is exceptionally rare. After conducting a literature review, the clinical case was detailed and discussed. The injuries were managed with open reduction, internal fixation of the lunate dislocation, primary direct repair of the scapholunate ligament and thumb UCL tears utilizing suture anchor fixation, and surgical reinsertion of the FPL tendon.

In the face of the atypical presentation, we stress the importance of carefully assessing the lesion and searching for any associated injuries both clinically and radiologically, particularly if a comprehensive evaluation was not possible.