Background: Investigation of trapeziometacarpal joint instability was undertaken following Bennett's fracture-dislocation.
Methods: We treated six patients who were experiencing trapeziometacarpal joint instability following Bennett's fracture-dislocation. The average age of the patients at the initial visit was 22.2 years. There were four men and two women. All six patients complained of trapeziometacarpal joint pain and instability preoperatively. Fluoroscopy confirmed that the beak fragment moved with the shaft fragment. The length of time from injury to surgery ranged from 1 to 29 months (average 10.7 months). Ligament reconstruction based on Eaton's method was performed on five patients, and in one patient the fracture site was osteotomized and reduced and the dorsoradial ligament repaired.
Results: Over an average follow-up observation period of 20 months, none of the patients complained of severe joint pain or instability.
Conclusions: When treating Bennett's fracture-dislocation, it is necessary to pay careful attention not only to accurate anatomic reduction of the joint surface but also to joint instability.