To evaluate the usefulness of interlocking intramedullary nailing for operative treatment of forearm shaft fractures in adults.

Thirteen forearm shaft fractures in 12 patients were fixated with 13 Acumed forearm intramedullary rods (ulna: 8, radius: 5). The average age was 36.7 years and mean follow-up period was 15.2 months. The union time was measured when there was no tenderness over the fracture site and the bridging callus was evident in at least two sides of the cortex. The range of motion of the joint and the rotation of the forearm was measured and the functional results were evaluated with Grace and Eversmann's rating system.

Radiologic union was observed at 11.8 weeks postoperatively in 11 cases out of 13. No limitation of motion was observed. Nine had excellent or good functional results. In one Galeazzi fracture, radial shaft became displaced after nailing and should be re-stabilized with plate. Proximal interlocking screws were improperly inserted in one ulnar nail. Implants were removed in 7 cases. Removal guide screw was broken while removing the intramedullary nail in one case of ulnar shaft fracture.

Interlocking intramedullay nailing might be a treatment option for the middle 1/3 shaft fractures of the adult forearm bone with favorable results.