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Updated: May 23, 2026

Establishment and Evaluation of a Sheep Model of Full-thickness Osteochondral Defect
Published on: April 14, 2026
Nutrition and degeneration of articular cartilage
Yuze Wang1, Lei Wei, Lingyuan Zeng
1Department of Orthopaedics, The Second Hospital of Shanxi Medical University, 382 Wuyi Road, Taiyuan, 030001, Shanxi, People's Republic of China.
Purpose:
To determine the importance of synovial fluid (SF) or subchondral bone marrow (BM) as nutrition sources in cartilage degeneration.
Methods:
Ninety-five-month-old male rabbits were randomly divided into 5 groups according to sources of nutrition: SFBM-both; BM-only; SF-only; None-SFBM; and Free plug (unrestricted). Nutrition to 4-mm-diameter cylindrical osteochondral plugs created on the trochlea of the distal femurs was obstructed by Polyvinyl Chloride (PVC) cap. Cartilage changes were assessed after 4, 8, and 12 weeks by histology, immunohistochemistry, and real-time PCR.
Results:
Cartilage in the BM-only group suffered the greatest damage, followed by the None-SFBM and SF-only groups. Apoptosis was increased in the BM-only and None-SFBM groups compared with others. Cartilage was significantly thinner at all time points in the BM-only and None-SFBM groups when compared with SFBM-both and Free plug, whereas in the SF-only group, this difference occurred after 8 weeks. Compared with SFBM-both and Free plug, expression of collagen II and aggrecan mRNAs in all groups was decreased but MMP-3 increased, respectively.
Conclusion:
Our data indicate that SF-derived nutrition is the dominant source of sustenance for adult cartilage structure and function. Cartilage damage is observed when the only nutrition source is the BM.
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