Fifty-four adult patients with unstable or displaced distal ulna fractures were randomized to receive either elastic stable intramedullary nails (ESIN, n=26) or locking compression plates (LCP, n=28). The primary outcome was the functional result measured using the Gartland-Werley scoring system. Secondary outcomes included perioperative metrics (incision length, operative time, fluoroscopy frequency), radiographic union time, complication rates, and wrist range of motion. Outcomes were assessed at intervals up to two years postoperatively. Overall, the results of the study revealed that the ESIN group had shorter operative time, smaller incisions, fewer complications, and better functional outcomes compared to the LCP group. These findings suggest ESIN is a minimally invasive, effective alternative for treating unstable distal ulna fractures in adults.