Using Cartilage Extracellular Matrix (CECM) Membrane to Enhance the Reparability of the Bone Marrow Stimulation Technique for Articular Cartilage Defect in Canine Model

Bone marrow stimulation techniques (BSTs) are widely used in clinics to treat cartilage defects, but yet have a critical limitation from the loss of blood clots. In this work, a novel cartilage extracellular matrix (CECM) membrane is developed to protect blood clots after BSTs. The CECM membrane was made of ECM fabricated naturally by cultured porcine chondrocytes, and then decellularized and multi-layered to confer optimal mechanical strength. Highly compatible with cells, the CECM membrane did not show any cytotoxicity or immune responses in vivo. The CECM membrane was very thin (3060 mu m thick) and bendable, but had good tensile strength (85.64 N), suitable for protecting blood clots from leakage in rabbit cartilage defect. Moreover, the CECM membrane showed low but enough diffusion coefficient to allow delivery of small proteins in synovial fluid into the repaired tissue. In a beagle model, covering the cartilage defect with the CECM membrane after BST generated more hyaline cartilage-like tissues than the BST alone in histology and chemical analyses at 18 weeks. Its ICRS score was approximately 2.5 times higher than that of the BST alone. Therefore, the CECM membrane is proposed as a useful tool that can improve the outcome of BSTs to treat cartilage defects.