Can We Improve Screening Costs in Asymptomatic Metal on Metal Total Hip Arthroplasties?

Introduction: Metal on Metal (MoM) total hip arthroplasty (THA) has been largely abandoned in the United States secondary to high failure rates. Many of the failures are attributed to adverse local tissue reactions (ALTR). Therefore, patients that have a MoM THA are routinely screened by checking serum metal ion levels every two years, as was recommended by the FDA. However, there is limited data on the costs of current screening protocols. Materials and Methods: 318 consecutive patients who underwent a MoM THA at a single institution were retrospectively enrolled. The average follow-up was 8.2 years. Clinical data, metal ion levels, revision and reoperation rates were prospectively collected. The costs of clinical screening for this patient population was calculated and compared to the cost of an annual screening protocol. Results: 12 patients had either an elevated Co or Cr level (>4.5 ppb). Eight patients were revised secondary to ALTR. The total cost of screening during the study was $612,250. Additionally, if annual screening had been performed, total screening costs would be approximately $1,719,200. Discussion: Eight patients in the following study were revised secondary to ALTR with a total cost of screening of $612,500. These costs are substantially less than the cost of annual screening ($1,719,200). Due to the considerable costs of screening asymptomatic MoM THA patients, we recommend both optimizing the frequency of screening and evaluating the specific risk of the implant being screened.