Prevalence of self-reported metal allergy in patients undergoing primary total knee arthroplasty.

No validated screening method exists to identify patients at risk for metal allergy complications following total knee arthroplasty (TKA). Select use of implants that do not contain nickel, cobalt, and chromium may be considered in patients at risk. This study was performed to determine the rate of self-reported cutaneous metal allergy, or sensitivity, in patients undergoing knee replacement, and to evaluate whether there is a higher prevalence in females. A retrospective chart review was performed on 194 consecutive patients who underwent primary knee arthroplasty with a single surgeon between 2010 and 2011. During this period, all patients, except those with a previous well-functioning orthopedic device, were asked preoperatively about a history of metal allergy or sensitivity. The prevalence of self-reported cutaneous metal allergy, or sensitivity, was 14%; 22% (19/86) of females and 2% (1/53) of males reported a positive history. Fourteen percent of patients undergoing TKA self-identify as having a cutaneous metal allergy or sensitivity. Until validated screening tests are developed to identify patients "at risk" of symptomatic metal allergy after TKA, selective use of prostheses that do not contain cobalt, chromium, or nickel in individuals who self-identify with metal sensitivity may be considered. As most of these patients are female, manufacturers should consider optimizing availability of these implants in smaller sizes.