Total Knee Replacement in Alkaptonuric Ochronosis.

BACKGROUND AND OBJECTIVE

Alkaptonuria is a rare disease characterized by the accumulation of homogentisic acid (HGA). Over time, these patients may develop disabling ochronotic arthropathy. We present 2 cases of patients with end-stage arthropathy treated with total knee arthroplasty (TKA).

METHODS

Both patients complained of disabling knee pain and reported limited walking distance (200-300 m). One had a history of osteotomy for medial knee arthtritis and ignored his underlying condition. The other presented with valgus gonoarthrosis and diagnosis of alkaptonuria.

RESULTS

Intraoperatively, the characteristic dark-blue color in the joint was observed. Both patients evolved favorably after TKA with excellent results according to the Knee Society Scores (KSS) at three years of follow-up.

CONCLUSION

We believe TKA is the right treatment for patients with end-stage disease because it offers considerable relief from pain and allows patients to recover function.