Resurfacing matched to standard total hip arthroplasty by preoperative activity levels - a comparison of postoperative outcomes.

BACKGROUND: Some studies have suggested that resurfacing patients are generally more active postoperatively than their conventional total hip arthroplasty (THA)counterparts, but controversy remains over whether this is a reflection of preferential use of resurfacing for younger and higher-activity patients. We hypothesized that, when controlling for preoperative activity levels, in addition to relevant clinical and demographic factors, resurfacing provides similar results to conventional hip arthroplasty.

MATERIALS AND METHODS: The specific question asked was whether resurfacing patients had differences in postoperative activity level, clinical outcomes, or rate of revisions, as compared to a matched cohort of patients treated with conventional THA. Thirty-three patients (23 men and 10 women) who were treated with resurfacing arthroplasties were matched to a cohort of patients who underwent conventional hip arthroplasty by gender, age, body mass index (BMI), and preoperative activity level. Mean preoperative Harris hip scores and length of follow-up were similar for the two groups. Postoperative weighted activity scores, Harris hip scores, patient satisfaction score, pain scores, and revision rates were evaluated at a mean final follow-up of 42 months (range, 25 to 68 months) for the resurfacing group and 45 months (range, 24 to 67 months) for the conventional hip group, and analyzed for differences.

RESULTS: At final follow-up, activity levels were significantly higher in the resurfacing group, with a mean weighted activity score of 10.0 points (range, 1.0 to 27.5 points), as compared to a mean score of 5.3 points (range, 0 to 12.0 points) in the THA group. Mean Harris hip scores, patients satisfaction scores, and pain scores were similar for both groups. There were no revisions in either group.

CONCLUSIONS: The results of this study suggest that patients treated with hip resurfacing arthroplasty have a significantly higher postoperative activity level, as compared to those treated with conventional THA, when controlled for preoperative factors.