HIP RESURFACING: INDICATIONS AND EXPECTATIONS

Abstract

Metal on metal total hip resurfacing is a bone-conserving reconstructive option for patients with advanced articular damage. The optimal indications for this procedure are being defined by recent international experience. This study evaluates the minimum two-year results of resurfacing arthroplasty compared to conventional hip replacement in young patients with a variety of diagnoses.

Resurfacing arthroplasty was performed in 180 patients over 5 years as part of two investigational device trials. The focus of this analysis was 57 hips (52 patients, mean age 47.3 years) performed between December 2000, and November 2003, by one surgeon at a single center. Seventeen percent of the resurfacing cases were performed for treatment of osteonecrosis. These patients, representing the initial experience of the operating surgeon, were followed prospectively for a minimum of two years (mean, 2.95 years, range, 2–4 years) and compared to 93 cementless primary total hip arthroplasties (84 patients, mean age 57.1 years) with metal on polyethylene bearings over the same time period using regression analysis to control for age, gender, and preoperative function.

After controlling for age and preoperative differences, the total Harris hip score (HHS), function score, and pain score were not significantly different between the two groups. However, the activity score (p=0.03) and ROM score (p< 0.001) were significantly greater in the resurfacing group. The complication rates were similar between the two groups (14.0% THA vs. 5.3% resurfacing, p=ns). There were no femoral side failures among the osteonecrosis cases treated with hip resurfacing.

Both the total hip replacement and metal on metal resurfacing groups showed marked improvement in HHS, pain, activity, and range of motion in a young and active patient cohort. The number of early complications was not greater in the resurfacing group compared to the total hip replacement group.