In 67 diaphyseal femoral fractures in adults treated by plating, the average follow-up time was 5 years. Sixty per cent of the patients suffered multiple injuries; 69% of the fractures were comminuted. The goal of treatment was rigid internal fixation. However, bridging of the comminuted area with a plate was sometimes necessary to maintain length as well as to encourage reconstitution and revascularization of fragments. Almost all patients had satisfactory end results. Only 2 cases were rated poor. Patients with rigid interfragmentary fixation had few complications, while patients with obvious instability (14 cases) developed 2/3 of the complications. The infection rate was 3%. Some complications might have been avoided by early cancellous bone grafting. The study confirms the need for primary or early secondary bone grafting to ensure bony union if cortical defects, potentially unstable fixation, or devascularized fragments are present.