ABSTRACT
INTRODUCTION: Metallic implants are integral to the practice of orthopedic surgery. Delayed-onset T-cell-mediated metal hypersensitivity (diagnosed by patch testing) is reported in 10% to 17% of the general population. Inconclusive evidence exists about the role of metal hypersensitivity in persistently painful or aseptic loosening of arthroplasties. Literature suggests that preoperative patch testing may influence surgical practice. OBJECTIVE: To determine the incidence of metal hypersensitivity in orthopedic surgical patients who self-report hypersensitivity and to characterize which metals are most commonly implicated. METHODS: A retrospective chart review of patients from a single surgeon's practice was conducted during a 1-year period. All patients were questioned about metal hypersensitivity history; all patients who responded affirmatively were sent for patch testing for specific metals. RESULTS: Only 41 (4.9%) of 840 patients self-reported any metal hypersensitivity. Of these, 34 (83%) were patch-test positive to 1 or more metals. There were 27 whose test results were positive for nickel, 4 each to cobalt or gold thiosulfate, and 1 each to tin or titanium. Seven patients had positive results to multiple metals, all of whom were also nickel hypersensitive. Six patients had metal orthopedic implants before patch testing, and 4 (67%) tested positively to a metal in their implant. CONCLUSION: Metal hypersensitivity can be concerning for treating surgeons and patients. Greater awareness of a history to hypersensitivity may prevent patient exposure to implants containing metals that may cause hypersensitivity. Non-metal-containing or nonreactive metal implants are an option for patients in whom metal hypersensitivity is suspected or confirmed.
