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Femoral and Acetabular Surface Replacement and Hemi-Surface Replacement for Osteonecrosis of the Hip

Summary: Hemi-resurfacing has been used for the past 20 years for the treatment of late-stage osteonecrosis of the femoral head. The indications at this point are limited to patients with later stages of the disease (University of Pennsylvania Stages III–VI) without apparent acetabular involvement. This should be viewed as a temporizing procedure. It is possible that if these do fail, that they can be left in place and converted to a femoral and acetabular resurfacing arthroplasty. More recently, femoral and acetabular resurfacing arthroplasty has been used for later stages of the disease. This appears to be a reasonable alternative to standard total hip arthroplasty. There are now approximately 10 reports of short- to mid-term follow-up showing excellent success rates (>95%) for using femoral and acetabular resurfacing hip arthroplasty in osteonecrosis patients. The authors await longer-term follow-up to see whether these results will be maintained.