Chronic dislocations of the fourth and fifth carpometacarpal joints with successful treatment by ligament repair: A case report and literature review.

Dislocations of the fourth and fifth carpometacarpal joints (CMCJs) are rare and often misdiagnosed via radiography. Moreover, treatment strategies have not yet been standardized. Herein, we report a case of chronic dislocations of the fourth and fifth CMCJs with delayed diagnosis and successful treatment via ligament repair. A 29-year-old male patient who was initially diagnosed with contusion at another center following a fall on the stairs was referred to our hospital one month later due to persistent pain and swelling. Fourth and fifth CMCJ dislocations were diagnosed using radiography and computed tomography. Closed reduction attempts were unsuccessful, prompting open reduction. The operative findings included rupture of the dorsal carpometacarpal ligament and hamate cartilage injury. Using two mini anchors, the fourth and fifth dorsal carpometacarpal ligaments were repaired, and Kirschner-wire (K-wire) pinning was performed. The K-wire was extracted after four weeks. At the eight-month follow-up, the only remaining symptom was mild discomfort, and the range of motion and grip strength was fully recovered. Our findings highlight the difficulties in diagnosing CMCJ dislocation and suggest ligament repair as a treatment option for chronic cases of CMCJ dislocation.