Introduction:
Ochronosis is a rare syndrome caused by accumulation of homogentisic acid in connective tissue due to deficiency of enzyme homogentisic acid oxidase. It characterized by blue-black pigmentation connective tissues such as sclera, cartilage of ear, and synovium of joints and it causes destruction of joints cartilage and early arthritis. Urine becomes dark coloured on prolonged standing. Some patient may develop rare cardiac manifestation due to accumulation of homogentisic acid on valves.
Case report:
A 56-year-old female admitted with neck of femur fracture after history of fall at home. The patient was having chronic back ache and knee pain. Plain radiograph of knee and spine showed severe arthritic changes. Exposure during surgery was difficult due to hard and brittle tendons and capsule of joint. Femur head and acetabulum cartilage appeared dark brown. Dark brown pigmentation of sclera and hands was found on clinical examination postoperatively.
Conclusion:
Patients with ochronosis usually develop early osteoarthritis and spondylosis which should be differentiated from other causes of early arthritis such as rheumatoid arthritis and seronegative arthritis. It leads to destruction of joint cartilage and weaking subchondral bone which leads to pathological fracture. And due to the stiffness of soft-tissues around joint, surgical exposure can be challenging.