Surface arthroplasty for osteonecrosis of the hip -: Hemiresurfacing versus metal-on-metal hybrid resurfacing

Eighty-four hips with Ficat stage III and IV osteonecrosis were treated: 56 with metal-on-metal Surface arthroplasty (MMSA) and 28 with hemi-surface arthroplasty (HSA). Average follow-up was 4.9 years. UCLA hip scores were significantly better for MMSA versus HSA for function and activity as well as Harris Hip scores and physical component of the SF-12 scores. In the MMSA group, 2 hips were revised to total hip arthroplasty for femoral loosening, and 5 hips had adverse radiological changes. in the HSA group, 4 hips were revised (I sepsis and 3 for pain). There was no evidence of any femoral loosening or neck narrowing in the HSA group. Although the functional clinical outcome of MMSA is superior to HSA, long-term follow up of MMSA will determine the reliability of the femoral fixation. Key words: hip arthroplasty, metal-on -metal, osteonecrosis, resurfacing. (C) 2004 Elsevier Inc. All rights reserved.