Thirty-five patients who sustained humeral shaft fractures were treated by open reduction internal fixation using AO techniques between 1992 and 1997. Open fractures occurred in 8 patients. Primary radial nerve palsy was present in 5 cases. In 16 patients an open fracture or multiple trauma, or both were indications for surgery. Eight osteosynthesis were performed after failed conservative treatment. The complications encountered were non-union (2 cases), osteomyelitis (2 cases), secondary radial nerve palsy (3 cases) and repeat surgery (4 cases). Bony union averaged 5.3 months radiographically. All cases of radial nerve palsy recovered eventually. Twenty-seven patients reported no pain. Twenty-six patients had full range of motion in the shoulder and elbow. Thirty-three patients had full muscle strength. Open reduction internal fixation gives good results provided correct indications and principles of fixation are adhered, and is a good alternative to conservative treatment. We advocate operative reduction internal fixation and nerve exploration in fractures associated with radial nerve palsy.