Bipolar hemiarthroplasty for fracture of the femoral neck. Clinical review with special emphasis on prosthetic motion.

The results of a consecutive series of 120 bipolar replacements of the femoral head that had been done for the treatment of a fracture of the femoral neck were reviewed. Ninety patients were followed for a minimum of two years. At the latest follow-up, eighty-two (91 per cent) of the patients were free of major pain, and eighty-three (92 per cent) were considered to have satisfactory motion and muscle power. Postoperative function often was limited by underlying medical problems. Seventy-five patients (83 per cent) either returned to the level of function that they had had before the fracture or used only a cane, which they had not needed previously. There was no important deterioration of the results with time. For twenty-six of the prostheses, roentgenograms were made with the patient bearing weight in order to determine the relative motion at the two sites of articulation of the bipolar prosthesis. The roentgenograms demonstrated the presence and maintenance of motion at both bearing surfaces.