Thirty-two elderly patients with a femoral neck fracture treated by bi
polar hemiarthroplasty and 36 patients (matched for age) with an Austi
n-Moore hemiarthroplasty were followed-up and compared. Bipolar replac
ement resulted in a higher percentage of satisfactory results, less po
stoperative pain, greater range of movement, more rapid return to unas
sisted activity, fewer unsatisfactory results and no acetabular erosio
n. The device functioned as bipolar in all the cases studied for inner
-bearing motion.