A case series of Stener’s lesion of the first metacarpophalangeal joint

Abstract

Ulnar collateral ligament (UCL) injuries have a high prevalence however; these are usually being missed in the initial clinical evaluation. Depending on the chronicity of the injury there are two acronyms for UCL tear. One is the skier's thumb and the other is the gamekeeper's thumb. If the UCL of the first metacarpophalangeal joint (MCP joint) has a complete tear with entrapment of aponeurosis of adductor pollicis muscle between the MCP joint and torn ligament, is called a Stener’s lesion. This is a rare clinical entity that requires early surgical correction because of entrapment. The mechanism of injury is the coerced abduction of the thumb from the index finger, causing ligament tears or sprain with or without ensuing avulsion fracture. The incidence of Stener’s lesions associated with UCL rupture has been reported to be up to 52% per intra-operative finding. In Stener’s lesions, the UCL tears from the base of the proximal phalanx (PP) then retracts proximally and displaces superficial to the adductor pollicis. Here we are presenting four cases of Stener’s lesions, with the usefulness of magnetic resonance imaging (MRI) in diagnosing this entity, which can prevent possible long-term complications such as chronic pain, joint degeneration, and joint instability.