The Bateman bipolar prosthesis: a prospective study in primary osteoarthritis.

: We present a prospective study of Bateman bipolar prosthesis performed over 5 years in Perth. All patients were treated for primary osteoarthritis using a cementless straight Moore stem and the bipolar acetabular component. Assessment was made at 6-monthly intervals. Harris hip scores were calculated and radiological parameters of inner bearing movement, component migration and proximal osteoporosis were assessed. The group comprised 76 prostheses in 72 patients. The mean Harris hip score at 3 years follow-up was 85, however with a wide range between 55 and 99. A total of 30% of patients at 3 years follow-up had a Harris hip score at less than 70. Twenty-seven per cent of the prostheses at 3 years had restriction of movement at the inner bearing and 43% were judged to have moderate or severe stress shielding around the proximal femur. The clinical results were unpredictable with thigh pain being a significant problem. Because of the unpredictable results we would not advocate the use of the Bateman prosthesis in primary osteoarthritis.