Phonthakorn Panichkul, Henry Ho, Robert H. Hopper Jr and C. Anderson Engh Jr
Background: There remain concerns about the ability of community laboratories to accurately measure blood metal levels as one piece of the monitoring and treatment algorithms for patients with a metal-on-metal total hip arthroplasty (THA).
Question/purposes: The purpose of this study is to compare serum cobalt and chromium levels obtained from one group of patients at a single reference laboratory to levels from a different group of patients measured at multiple community laboratories.
Methods: We compare serum metal levels performed prospectively at a single reference laboratory on 57 patients to levels performed retrospectively on 160 patients in community laboratories. All patients had unilateral metal-on-metal bearing hips. Metal levels were measured at 1, 2, 3 and 5 years post-op.
Results: There was no difference between community and reference groups in mean values, median values or the number of cases with values greater than 7 μg/L at any time interval.
Conclusions: We conclude that metal level values drawn in the community are similar to values obtained in tightly controlled prospective studies.
Level of evidence: Level I, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.
