Carpometacarpal Fracture-Dislocations: A Retrospective Review of Injury Characteristics and Radiographic Outcomes

Background: The purpose of this study was to evaluate the demographics and early radiographic treatment outcome of patients with carpometacarpal (CMC) injuries at our institution over a 10-year period. Methods: We conducted a retrospective review of all patients who sustained CMC injuries of the second to fifth digits between 2005 and 2015. We recorded demographic data, mechanisms of and associated injuries, treatment methods, and complications. Injury and intraoperative and postoperative radiographs were evaluated, and the adequacy of reduction was determined on lateral radiographs of the hand using a grading system that we developed. Results: Eighty patients were included in this study. Delivering a blow with a closed fist was the most common mechanism of injury; however, high-energy mechanisms also made up a large percentage of those included. Injuries to the fourth and fifth CMC joints were most common, and these were frequently associated with fractures of the metacarpal bases and distal carpal row. Closed reduction and percutaneous pinning offered a higher percentage of patients with concentric reduction at the time of pin removal. Time to surgery was significantly different between those with concentric reduction and those with residual subluxation. Conclusion: The most common mechanism of CMC injuries was blow with a closed fist; however, these injuries can be associated with high-energy mechanisms. Fractures of the metacarpal base and distal carpal row are commonly seen with these injuries. With early diagnosis, closed reduction and percutaneous pinning achieved concentric radiographic reduction. Delayed diagnosis makes closed reduction difficult and was associated with less favorable radiographic outcome.