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Updated: May 9, 2026

Establishment and Evaluation of a Sheep Model of Full-thickness Osteochondral Defect
Published on: April 14, 2026
[Arthropathia ochronotica: a rare cause of early joint degeneration]
S Freche1, E Esmer, K-S Delank
1Abteilung Orthopädie, Universitätsklinikum Halle/Saale, Germany. sven.freche@uk-halle.de
History And Admission Findings:
A 70-year-old deaf-mute women suffered from progressive chronic pain of the right hip joint caused by destructive osteoarthritis of the hip.
Investigations:
In addition to painfully restricted range of motion of the right hip joint the clinical examination showed a bluish-black pigmentation of the ear-cartilage and the sclera.
Treatment And Course:
A total endoprosthetic replacement of the right hip joint was performed. During surgery, blackening of the hip joint capsule and cartilage was found. Histological, the diagnosis of an ochronosis was confirmed. Discoloration after exposure of urine to air supported the diagnosis. Based on extensive internal medical examination relevant cardiac changes were excluded.
Conclusion:
Ochronosis (arthropathia ochronotica) is a rare entity which can be identified by a visual diagnosis. Early diagnosis can provide crucial information for the prognosis. Additionally, an interdisciplinary treatment concept should be established because of the early onset of degenerative changes at the skeletal system and pathological changes at internal organs. With suspicion on an ochronosis extended internal examinations are recommended in order to avoid complications.
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