Bipolar femoral head arthroplasty in osteoarthritis. A prospective study with a minimum 5-year follow-up period.

Primary bipolar femoral head arthroplasties performed on 100 osteoarthritic hips were studied to a minimum of 5 years after surgery. All arthroplasties were performed on physically active patients. At a mean follow-up period of 5.5 years, The Hospital for Special Surgery hip scores were good to excellent in 96 hips. Transient startup soreness constituted the most frequent complaint, occurring in 34 hips. Three hips had more persistent pain localized to the acetabulum, necessitating revision to fixed sockets, which alleviated the symptoms. Four additional hips, in heavy, active men, developed polyethylene fatigue fracture and component disassembly. Acetabular migration of more than 5 mm developed in one hip. Motion, as determined radiologically, occurred primarily at the inner bearing. There were no dislocations or infections in the series. The Bateman bipolar prosthesis provides generally good results in osteoarthritic hips. The shorter operating time and the case of revision are special advantages of bipolar devices. Start-up soreness and stiffness is a shortcoming in approximately one third of cases. Component disassembly in heavy, active men is a problem and the bipolar arthroplasty should be avoided in these patients. Start-up soreness was a significant problem in particular.