Resurfacing Versus Conventional Total Hip Arthroplasty: Review of Comparative Clinical and Basic Science Studies (Clinical Report‪)‬

Modern total hip arthroplasty (THA) designs and surgical approaches have shown excellent long-term results for the treatment of late-stage symptomatic osteoarthritis, especially in older, less active patients. Some concerns exist that THA may provide less optimal outcomes in younger and more active patients. As such, there has long been an interest in more boneconserving replacement procedures, such as resurfacing hip arthroplasty (RHA). Earlier generations of hip resurfacing devices frequently failed, largely due to problems with excessive wear of their bearing surface materials. Since that time, improvements in surgical technique and design, specifically the introduction of thinner shelled metal-on-metal interfaces with improved tolerances, have led to a renewed and growing interest and use of resurfacing, especially in young and active patients. Since the introduction of metal-on-metal resurfacing devices, in the 1990s, over 300,000 procedures have been performed worldwide. (1) Multiple studies of short- and midterm outcomes of resurfacing implants have reported clinical success rates upwards of 94%, (2) with several studies reporting five-year survival rates of 98%. (3,4) These outcomes are similar to those that have been reported for patients treated with conventional THA. Some investigators have argued that resurfacing may offer advantages over THA, in terms of conservation of femoral bone stock, increased range of motion (ROM), a more normal gait pattern, lower dislocation rates, and ease of revision. In order to assess these claims, a number of investigators have conducted studies directly comparing THA and RHA. These studies have varied in their approach in terms of the outcome parameters used to assess THA and RHA.