Improved repair of chondral and osteochondral defects in the ovine trochlea compared with the medial condyle

Abstract

Associations between topographic location and articular cartilage repair in preclinical animal models are unknown. Based on clinical investigations, we hypothesized that lesions in the ovine femoral condyle repair better than in the trochlea. Full-thickness chondral and osteochondral defects were simultaneously established in the weightbearing area of the medial femoral condyle and the lateral trochlear facet in sheep, with chondral defects subjected to subchondral drilling. After 6 months in vivo, cartilage repair and osteoarthritis development was evaluated by macroscopic, histological, immunohistochemical, and biochemical analyses. Macroscopic and histological articular cartilage repair and type-II collagen immunoreactivity were better in the femoral trochlea, regardless of the defect type. Location-independently, osteochondral defects induced more osteoarthritic degeneration of the adjacent cartilage than drilled chondral lesions. DNA and proteoglycan contents of chondral defects were higher in the condyle, reflecting physiological topographical differences. The results indicate that topographic location dictates the structural patterns and biochemical composition of the repair tissue in sheep. These findings suggest that repair of cartilage defects at different anatomical sites of the ovine stifle joint needs to be assessed independently and that the sheep trochlea exhibits cartilage repair patterns reflective of the human medial femoral condyle. ß

A novel algorithm for a precise analysis of subchondral bone alterations

“…Finally, the different location of the defects in the two animal models (trochlear groove versus femoral condyle) may weaken the algorithm. As cartilage repair differs in the sheep trochlea compared with the medial femoral condyle21, the suggested thresholds for bone cyst and peri-hole resorption may need to be adapted accordingly if the extent and pattern of subchondral bone alterations are similarly topographically dependent.…”

Osteochondral Tissue Engineering with Biphasic Scaffold: Current Strategies and Techniques

“…[29][30][31][32][33][34][35] As a strategy to regenerate these structures in a layer-by-layer fashion, biphasic or triphasic constructs have been developed due to both mechanical and biological reasons, including the acquisition of initial mechanical strength, mimicking a natural articulate structure, a uniform tidemark at the osteochondral junction, and integration of the biphasic implant with host tissue to sustain biological function. 7,[36][37][38][39][40][41][42][43][44] For satisfying the biological requirements, an osteochondral implant should ideally have a rigid osseous layer (to support the overlying cartilage and integrate with the native bone) and a chondral layer (to enable the seeding and proliferation of chondrocytes or mesenchymal stem cells (MSCs) and subsequent deposition of cartilaginous ECM).…”

Current management of talar osteochondral lesions

“…This destruction is a result of the surgical trauma and compaction of the SCB plate that occurs with penetration of either a microfracture pic or drilling[27]. In the sheep osteochondral lesion model, Orth et al[28] revealed that the SCB plate was not restored at 6 mo after BMS. This finding was supported in the human ankle by Reilingh et al[29] which revealed that the SCB were not filled completely in 78.6% (44 of 58) OLT at 1 year after BMS.…”