Functional performance after hip resurfacing or total hip replacement: a comparative assessment with non-operated subjects.

Summary Introduction Several studies reported better clinical results with total hip resurfacing than with conventional total hip replacement, including in young patients, but without comparative stabilometry assessment. Hypothesis Resurfacing arthroplasty provides better functional performance than conventional total hip replacement. Objectives To test the above hypothesis in a stabilometry study comparing balance and functional performance in patients with total hip resurfacing or conventional total hip replacement and healthy controls. Materials and methods Results were analyzed on three cohorts of 20 patients: healthy control subjects, with unilateral total hip replacement or unilateral total hip resurfacing. The 40 operated patients were comparable in gender, age, weight (body-mass index), date of operation and clinical results. The 20 control subjects were younger and served as reference. Balance analysis employed a force platform commonly used in stabilometry, standardizing both leg or single leg stance balance analysis. The software interpreted individual balance by measuring plantar pressure center variation during the analysis so as to contour an individual both leg or single leg area of balance (statokinesigram, in mm 2 ). Results Balance analysis on both leg found comparable results in the control and resurfacing groups. The weight-bearing statokinesigraphic both leg balance area was greater in the hip replacement than in either of the other two groups ( p p p Discussion and conclusion The present functional performance results confirm the advantage of resurfacing over conventional hip replacement, and help explain the excellent radioclinical results reported for total hip resurfacing. Level of evidence III, comparative case-control study.