82 patients scheduled to undergo primary hip replacement due to osteoarthritis were randomized to receive either resurfacing hip arthroplasty or total hip arthroplasty. The purpose of this study was to assess whether hip resurfacing is associated with superior functional results, and evaluate metal ion blood levels as compared to standard hip arthroplasty. Results indicated that patients who had undergone resurfacing hip arthroplasty experienced superior mid-term (up to 2 years) function to those who had undergone total hip arthroplasty. Resurfacing hip arthroplasty patients also had higher levels of metal ions in their blood, and although their levels were within the safety margin, this indicated an increased risk for metal toxicity.