ORLANDO, Fla. — Among patients who reported metal allergy, investigators found decreased functional outcomes following total knee arthroplasty and decreased mental health scores following total hip arthroplasty, according to a speaker here.
“The clinical impact of metal sensitivity and allergic reactions have received increased attention following total hip arthroplasty, and this has largely been due to the recognition of catastrophic, aseptic reactions with large-diameter metal-on-metal bearings, tapered trunnion corrosion and associated with modular neck prostheses,” Denis Nam, MD, recipient of the Orthopaedic Research and Education/Current Concepts of Joint Replacement (CCJR) Clinical Award Paper, said at the CCJR Winter Meeting.
He continued, “However, the diagnosis of a true metal allergy remains difficult. The association between cutaneous reactions and a response to an implanted device remains unclear.”
Nam and his colleagues designed a study to identify the overall incidence of patients who reported a metal allergy and to assess the impact of self-reported metal allergies on clinical outcomes following total joint replacement.
The retrospective study included 589 patients who underwent elective total knee arthroplasty (TKA) and 906 patients who underwent elective total hip arthroplasty between 2009 and 2011. All patients completed a preoperative questionnaire regarding their drug and environmental allergies. Researchers collected preoperative and postoperative UCLA activity scores, SF-12 scores, modified Hip Harris scores and Knee Society scores (KSS).
The incidence of patient-reported metal allergy was 1.7% before January 2010 and was 4% after January 2010. KSS function, symptom, satisfaction and expectation scores decreased in TKA patients who reported metal allergy. THA patients who reported metal allergy had decreased SF-12 mental scores.
Limitations of the study include that it was a retrospective review. “[Therefore], we can only infer an association between patient-reported metal allergy in clinical outcomes and cannot suppose causation, [and] psychiatric testing was not performed to identify potential associations with patient-reported metal allergies,” Nam said. – by Nhu Te
Nam D. Paper #27. Presented at: Current Concepts in Joint Replacement Winter Meeting; Dec. 14-17; Orlando, Fla.
Disclosure: Nam reports no relevant financial disclosures.