Articular cartilage has poor repair properties and poses a significant challenge in orthopaedics. Damage as a result of disease or injury frequently leads to formation of an osteochondral defect. Conventional repair methods, including allograft, autograft and microfracture, have a number of disadvantages in terms of cost, associated technical challenges and the requirement for multiple operations. A novel tri-layered scaffold developed in our lab, addresses this issue as it closely matches the structure and composition of osteochondral tissue. In vivo assessment was carried out in a caprine model by creating 6 mm × 6 mm defects in the medial femoral condyle and lateral trochlear ridge of each joint. Defects were implanted with the tri-layered scaffold and for comparison also with a market-leading scaffold, while some of defects were left empty, acting as a control. Assessment was carried out at 3 month, 6 month and 12 month time points. The quality of the repair at the various time points was graded macroscopically and microscopically by histological staining of the samples and also assessed using micro-CT (computed tomography) analysis.Background
Methods
The gradient structure of osteochondral tissue, with bone, calcified and cartilage regions, challenges the design of biomaterials for defect repair. A novel biomimetic tri-layered collagen-based scaffold, designed to replicate these 3 anatomical layers, has been developed within our group and has shown success as an off-the-shelf product in treatment of focal defects in several animal models by recruiting host cells and directing them to form bone and cartilage in the requisite layers. This study aimed to elucidate the mechanism by which the extracellular matrix macromolecules in the scaffold directed stem cell differentiation in each layer. Tri-layered scaffolds were divided into their three constituent layers. Each layer was individually seeded with rat mesenchymal stem cells (MSCs). Cell infiltration and proliferation, calcium production and sGAG formation were assessed up to 28 days.Background
Methods
