Complex metacarpophalangeal joint dislocation of the thumb: A delayed presentation successfully managed by dorsal open reduction

Abstract

Complex dislocations of the thumb metacarpophalangeal joint are rare injuries that may be difficult to manage when they are not recognised early. We report the case of a 23-year-old right-handed soldier who presented two weeks after a fall onto the palm of the left hand, with a painful deformity and loss of motion of the thumb. Clinical examination and radiographs showed a dorsal dislocation of the thumb metacarpophalangeal joint with widening of the joint space and abnormal position of the sesamoid bones, suggesting interposition of the volar plate. Because closed reduction was considered unlikely to succeed, dorsal open reduction was performed. Intraoperative findings confirmed incarceration of the avulsed volar plate and periarticular fibrosis. After careful release of the interposed tissues, the joint was reduced and stabilised with two crossed Kirschner wires, and immobilised in a thumb spica splint for six weeks. At 78 months of follow-up, the thumb metacarpophalangeal joint was painless and stable, with almost full range of motion and return to full military duties. This case shows that even when treatment is delayed, anatomical reduction and temporary stabilisation can provide an excellent long-term functional outcome in complex dorsal dislocation of the thumb.