Bilateral hip and bilateral knee arthroplasties in a patient with ochronotic arthropathy.

Alkaptonuria is a rare, autosomal-recessive, inborn, metabolic disease that causes ochronotic arthropathy leading to disabling arthritis. Few reports of arthroplasty in patients with this disease have been published, and none documents four total joint replacements in the same patient. This case report describes the history and findings in a 70-year-old man who underwent bilateral hip and knee total joint arthroplasties with significant improvement in pain and exercise tolerance. The metabolic and clinical aspects of alkaptonuria are also discussed.