Metal Ion Levels in Young, Active Patients Receiving a Modular, Dual Mobility Total Hip Arthroplasty

Abstract Background Dual mobility total hip arthroplasty (THA) components improve stability, yet use of a modular cobalt-alloy acetabular liner may be associated with metal ion release. This study’s purpose was to measure blood metal ion levels in young, active patients receiving a dual mobility THA prosthesis. Methods This was a prospective study of young, active patients undergoing primary THA. 26 patients received a 22mm cobalt alloy (n=10) or 28mm ceramic (n=16) femoral head, a modular cobalt chrome acetabular liner, with a highly cross-linked polyethylene insert (dual mobility). 17 control patients received a 32mm cobalt alloy (n=6), oxidized zirconium (n=5), or ceramic (n=6) femoral head and polyethylene acetabular liner (conventional). All patients received a cementless, titanium femoral stem. Blood metal ion levels ( u g/L) were measured preoperatively and at 1 year postoperatively. Results No difference was present for age or body mass index (p=0.5 and 0.9). At one year postoperatively, mean cobalt levels were greater in the dual mobility cohort (0.23 + 0.39 vs. 0.15 + 0.07, p