Orthopedic Manifestations of Ochronosis: Pathophysiology, Presentation, Diagnosis, and Management.

Ochronotic arthropathy occurs in patients with alkaptonuria, manifesting first in the intervertebral discs of the lumbar spine, with subsequent degeneration most often observed in the knee, hip, and shoulder joints. Efforts at treatment are targeted at minimizing the damaging effects of the underlying metabolic disorder on the articular cartilage. Vitamin E and N-acetyl cysteine are potential therapies because of their scavenging of free radicals and consequent limitation of oxidative damage to joint tissue. Arthroscopy has been found to be an effective diagnostic tool in cases of suspected ochronosis. Arthroplasty performed in patients with ochronotic arthropathy suggests that the procedure is effective in the alleviation of joint pain and the improvement of mobility. Perioperative management of these patients may require more careful consideration pertinent to the associated comorbidities of this disorder.