Intramedullary screw fixation has emerged as a popular approach for the treatment of displaced metacarpal fractures. The purpose of this study was to investigate the functional and radiographic outcomes of a newly designed, headless noncompressive fully threaded intramedullary nail (TIMN) for the treatment of metacarpal fractures. A retrospective chart review was performed on patients who were treated with the INnate TIMN (ExsoMed) at a single academic institution with a minimum of 1-year follow-up. Patient-reported functional outcomes included Quick Disabilities for the Arm, Shoulder, and Hand (QuickDASH) questionnaires, return to work and physical activity time, and overall satisfaction. Radiographs were retrospectively reviewed to determine radiographic union, change in angulation, and metacarpal shortening. A total of 49 patients (58 fractures) with a mean age of 36 years (range: 17-75 years) were included. The mean follow-up time was 2.7 years (range: 1.4-4.3 years). Overall, the mean patient satisfaction rating was 4.9 of 5 (range: 3-5). The mean return to work time was 7.2 weeks (range: 0.14-28 weeks), and the mean return to sport or activity was 8.3 weeks (range: 1-28 weeks). Average QuickDASH scores across all patients were 4 (range: 0-56.9). The median radiographic healing time was 6.1 weeks (range: 4.7-15.4 weeks). Mean postoperative shortening in the fifth metacarpal fracture was 3 mm (range:-4.2 to 8 mm) at the initial postoperative visit and 3.6 mm (range:-3.3 to 7.9 mm) at the final radiographic follow-up. Subgroup analysis showed that postoperative shortening was similar, regardless of the fracture pattern. The following four complications were reported: one case of persistent pain and stiffness, one case of carpal tunnel syndrome, one nonunion, and one fractured intramedullary nail. Our findings suggest that the TIMN allows for a reliable return to work and physical activity, high patient satisfaction, low complication rate, and minimal shortening at the final radiographic follow-up. Therapeutic IV.