Type IV Cell-Mediated Hypersensitivity Reaction Caused by Titanium Implant Following Medial Displacement Calcaneal Osteotomy and First Metatarsal-Cuneiform Arthrodesis

INTRODUCTION AND OBJECTIVES: Due to its inert character and desired biocompatibility, titanium (Ti) implants have been universally accepted as safer alternatives to the previous conventional orthopedic hardware implants. However, a recent emergence of Type IV hypersensitivity reactions to Ti have displayed symptoms that include eczema, contact dermatitis, prolonged fever, sterile osteomyelitis, and impaired fracture and wound healing. The following case presents a patient with postoperative incision dehiscence and devascularization of cortical surfaces in contact with Ti hardware after undergoing a medial displacement calcaneal osteotomy and a first metatarsal-cuneiform arthrodesis. To our knowledge, this is the only reported case of an allergic reaction to a Ti implant in the foot or ankle in the United States. METHODS: Diagnostic tools to confirm a Ti hypersensitivity reaction include a patch test and lymphocyte transformation test. The lymphocyte transformation test can be utilized if a false negative ...