【Background】Cartilage injury in the knee joint is associated with trauma or degeneration, and greatly deteriorated the quality of their lives. Although several treatments for cartilage injury had been reported such as bone marrow stimulations, osteochondral autograft transfer system (OATS), and autologous chondrocyte implantation (ACI), several issues were remained for the quality of treatment and donor site. We focused on the cartilage scaffold for the cartilage repair without healthy donor invasion. Polyglycolic acid (PGA) and P(LA/CL) had been considered the good candidate for novel cartilage plug because we had already set up the meniscus scaffold with same materials. Therefore, the hypothesis of this study was that the novel cartilage scaffold induces the cartilage regeneration without healthy donor invasion.
【Purpose】To develop the plug-type cartilage scaffold (hereafter referred to as “cartilage plugs”) and evaluate the histological cartilage repair at porcine defect cartilage
【Methods】The cartilage plugs were fabricated by wrapping a PGA felt with a cage-like structure made of P(LA/CL) sutures and coated with a P(LA/CL) sponge. The diameter of the cage made of P(LA/CL) suture was 4.75 mm to fit the Arthrex OATS system (Arthrex Inc.).Cartilage defects were created in the patellofemoral joint of mini pigs with a diameter of φ4.75 x 10 mm. The cartilage plugs were divided into two groups, one containing hyaluronic acid and the other alone, and the defects were evaluated after 1 and 6 months and scored histologically for cartilage repair with Safranin O staining.
【Result】Both 1 and 6 months later, the hyaluronic acid-containing group showed better cartilage regeneration from safranin O staining. The cartilage plugs functioned as a scaffold, allowing migration of chondrocytes from adjacent normal chondrocytes, which was further enhanced by the inclusion of hyaluronic acid. Furthermore, in the histological characterization, the deposition of extracellular matrix in the defects was excellent.
【Conclusion】This cartilage plug type scaffold made by PGA coated with P(La/CL) might have the possibility of hyaline cartilage repair and containing hyaluronic acid. We believe that this will provide a new option for cartilage treatments.