Outcomes and Complications of Intramedullary Metacarpal Fixation

Background: Metacarpal fractures are common orthopedic injuries with potentially debilitating outcomes. Ideal surgical treatment remains a topic of debate, with intramedullary fixation becoming popular as a technique to allow for earlier mobilization with few reported complications. The aim of this study was to report observed outcomes and complications of intramedullary metacarpal fixation using the ExsoMed INnate metacarpal nail. Methods: A retrospective chart review of 37 patients with 44 metacarpals treated with the ExsoMed INnate between July 2020 and December 2021 by a single fellowship-trained hand surgeon at a single level 1 trauma center was performed. Variables recorded included both patient and injury demographics, surgical complications, and postoperative outcomes. We also measured metacarpal isthmus diameter of the second to fifth metacarpals on all patients to determine the intramedullary canal diameter to assist in implant size selection. Results: Average follow-up was 5.84 weeks with average time to radiographic healing of 5.5 weeks, and time to full activity 6.32 weeks. The mean postsurgical active total arc of motion was 250°, while passive total arc of motion was 259.74°. A total of 10 complications (22%) were identified, including 4 bent screws which occurred as a result of a punching event postoperatively. Conclusions: Intramedullary fixation of metacarpal fractures using the ExsoMed INnate metacarpal nail has shown to preserve range of motion and quick return to full activity, with a low rate of major complications. Our study highlights the potential major complication of the bent intramedullary screw and its association with an initial punching mechanism.