Clinical: 32 y/o female with thumb pain after bicycle accident.
Dx:
1. Complete avulsion/tear of the distal ulnar collateral ligament (UCL) from the phalangeal attachment. There is atypical radial displacement of the retracted ligament along the dorsal aspects of the 1st metacarpal head. The ligament is displaced by up to 10 mm and not in a position to heal with conservative management.
2. Complete avulsion of the ulnar component of the sagittal band of the thumb with associated radial dislocation of the extensor pollicis longus EPL relative to the 1st MCP joint. There is a strain of the EPL with some fraying centered in this region. No discrete EPL tear is identified.
3. Strains of the radial collateral ligament and 1st MCP joint capsule. There is disruption/avulsion of the dorsal capsule from the phalangeal attachment at the 1st MCP joint.
From the Surgeon: “The whole capsule was torn from the UCL to the RCL and the dorsal radial capsule was holding the EPL subluxed radially. The UCL was torn from the phalanx. The adductor-sagittal band complex was shredded, allowing the tendon to slide. I fixed ligaments/capsule with three anchors and repaired sagittal band.”
Read JHS article abstract here.
References:
Jaibaji M, Rayan G, Chung K. J Hand Surg: 2008 – vol. 33A, pp. 879-884.