Fractures and dislocations of the forearm are commonly observed in trauma clinics. With time, there will probably be significant increases in fractures of the forearm associated with traffic and sports. The efficacy of the treatment of ulnar fractures by a new locking nail, developed by Lefevre in Strasbourg, was tested in 20 patients. The fractures were severely displaced ulnae or both bones of the forearm. The minimum follow-up period was six months. The average age of the patients was 33.5 years (range, 14-77 years). The nail is placed into the ulna proximally. Locking is achieved by two screws placed at the proximal and distal end of the nail. The healing time for the fractures of both bones of the forearm ranged from 75 days to 20 weeks, with an average of 15 weeks. Healing time for the ulnar fractures ranged from eight to 20 weeks, with an average of ten weeks. The advantages of this nail were easy closed technique, compression effects at the fracture site, and enough stability so that an external support and tourniquet, in isolated ulnar fractures, were not necessary.