A new type of fixation device for the treatment of pertrochanteric fractures of the hip is described. The device has an axial-compression screw to allow compression along an axis parallel to the femoral shaft. As the fracture settles postoperatively, dynamic axial compression continues. This axial-compression device was used in twenty-five patients who had an unstable intertrochanteric or proximal subtrochanteric fracture of the proximal part of the femur. The average extent of axial impaction or settling was five millimeters (standard deviation, 1.3 millimeters) at the most recent follow-up examination, and the relationship between the femoral head and shaft was altered less than with the use of a conventional compression screw-plate device. A larger proportion of the patients who had the new device were able to walk fifteen meters (fifty feet) independently by the time of discharge from the hospital, even though they left the hospital earlier. No technical failures were seen in the patients who were treated with the axial-compression screw device. We believe that the axial-compression screw-plate device is appropriate for the treatment of unstable pertrochanteric fractures of the hip.