Type IV Cell-Mediated Hypersensitivity Reaction Caused by Titanium Implant Following Double Calcaneal Osteotomy and First Metatarsal-Cuneiform Arthrodesis: A Case Report and Review of the Literature.

Because of their inert character and desired biocompatibility, titanium implants have been universally accepted as safer alternatives to the conventional stainless steel orthopedic implants; however, recent emergence of type IV hypersensitivity reactions to titanium have included eczema, contact dermatitis, a prolonged febrile state, sterile osteonecrosis, and impaired fracture and wound healing. This report presents a patient with postoperative incision dehiscence and devascularization of surfaces in contact with titanium hardware after undergoing a double calcaneal osteotomy and a first metatarsal-cuneiform arthrodesis using titanium alloy implants. Titanium hypersensitivity was confirmed in this case through standard allergy patch testing by a board-certified immunologist. Complete healing occurred after diagnosis of the titanium allergy and hardware explant. To our knowledge, this is one of a few known allergies to titanium implants after foot and ankle surgery.