Prosthetic and Device Surgery Considerations

Abstract

Biomedical implants have a broad array of therapeutic uses, most commonly in orthopedic procedures, such as dynamic hip and knee replacements. There are also wide-ranging applications in cardiology, gynecology, and other specialties. Use of metal components will likely expand with further medical innovations. Hypersensitivity reactions to these devices are well documented but uncommon. Patch testing is currently the best evaluation for metal hypersensitivity reactions (MHR). Preimplant testing for asymptomatic individuals is not necessary. Patients with a history of skin rashes dermatitis after metal contact would likely benefit from preimplant testing. Those individuals with postoperative complications such as aseptic loosening; chronic pain; or new, unexplained local or regional dermatitis may benefit from evaluation for MHR. Metal allergy testing is never indicated in emergent or life-threatening situations. Whether prior to or after implant placement, collaborative efforts between the allergist and surgeon should determine the clinical plan. A positive test for metal allergy should not define treatment. When a metal allergy is revealed prior to implant, every effort should be taken to avoid the allergen(s). Often, titanium or oxidized zirconium alloys are the most appropriate choice for those allergic to stainless steel components. Clinical decision making after implantation is challenging. If the implant is asymptomatic, no action should be taken. Symptomatic patients following implant are more challenging. The surgeon and patient need to determine whether replacement with a non-allergenic alternative is feasible, necessary, and safe. Prospective trials in this field are still necessary to develop a more evolved and evidence-based approach to treatment of patients with MHR.