A rare case of pseudotumor formation associated with methyl methacrylate hypersensitivity in a patient following cemented total knee arthroplasty.

Hypersensitivity to orthopedic implant materials has been well documented with potential catastrophic consequences if not addressed pre-operatively. The spectrum of reactions is wide, from mild non-specific pain with localized erythema to severe periprosthetic inflammatory destruction and pseudotumor formation. It is therefore essential to identify patients who have or are at risk for implant-associated hypersensitivity.