LONGITUDINAL INSUFFICIENCY FRACTURES OF THE FEMORAL-SHAFT

Most insufficiency fractures of the femur are transverse fractures of the femoral neck, We report two 77-year-old female patients with longi tudinal fractures of the femoral shaft; one had a vertical fracture li ne in the proximal part of the shaft and the other a spiroid line in t he middle third of the shaft, Both patients experienced apparently spo ntaneous onset of incapacitating mechanical pain in the hip or thigh; duration of the pain at evaluation was ten days in one case and six mo nths in the other, Potential risk factors were osteoarthritis of the h ip and the presence of metalwork in the knee, Increased radionuclide a ctivity at the fracture site was seen on the bone scans, In one patien t, roentgenographic and computed tomography findings were normal and t he diagnosis was established by magnetic resonance imaging. In the oth er, the fracture line was seen clearly on computed tomography sections , Longitudinal fractures often escape diagnosis initially because roen tgenographic changes are delayed, Hyperactivity on the bone scan is su ggestive but sometimes so extensive as to mislead the diagnosis, The c allus and, less frequently, the fracture line are sometimes seen on co mputed tomography sections, The role of magnetic resonance imaging rem ains to be determined,