Intolerance reactions to knee arthroplasty in patients with nickel/cobalt allergy and disappearance of symptoms after revision surgery with titanium-based endoprostheses.

Intolerance reactions to metal implants may present as dermatitis, impaired wound healing, effusions, pain or loosening. The clinical relevance of metal allergy in the differential diagnosis is often unclear and patients may even tolerate implants containing metals to which they are allergic. We present four patients with knee arthroplasty in whom after exclusion of infection or mechanical causes, a nickel/cobalt allergy led to replacement surgery with titanium-based prostheses. The subsequent alleviation of symptoms underlined the relevance and usefulness of allergological diagnostics in selected cases of complicated arthroplasty.