Researchers from Cleveland Clinic (disclaimer: I had worked with several of them prior to 2008) conducted a chart review of 72 patients who had patch testing for allergic contact dermatitis related to orthopedic implants.
The 72 patients with potential metal hypersensitivity from implanted devices were divided into 2 groups depending on timing of their patch testing:
- pre-implantation (n = 31)
- post-implantation (n = 41)
History of hypersensitivity to metals was a predictor of positive patch test results to metals in both groups.
Positive patch test results indicating metal hypersensitivity influenced the decision-making process of the referring surgeon in all preimplantation cases.
All those patients with metal hypersensitivity who received an allergen-free implant had surgical outcomes free of hypersensitivity complications.
In patients who had positive patch test results to a metal in their implant after implantation, removal of the device led to resolution of associated symptoms (6 of 10 patients).
Patch testing should be perfomed in patients with a clinical history of metal hypersensitivity before prosthetic device implantation. The decision on whether to remove an implanted device after positive patch test results should be made on a case-by-case basis.
The Effect of Patch Testing on Surgical Practices and Outcomes in Orthopedic Patients With Metal Implants. Atanaskova Mesinkovska N, Tellez A, Molina L, Honari G, Sood A, Barsoum W, Taylor JS. Arch Dermatol. 2012 Feb 20.
Allergy Tests Needed Before New Knee or Hip. MedPage Today.
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