Abstract:

BACKGROUND: Polyvinyl alcohol hydrogel (PVA) has been generally considered as a good substitute material of articular cartilage. Polyamide 66 (PA66) polymer has achieved an extensive application in the fields of engineering and medicine owing to its high intensity, strong tenacity and good stability. Polyurethanes exhibit good histocompatibility and blood compatibility and show distinct advantages in repairing cartilage. 
OBJECTIVE: To compare the outcomes of repairing articular cartilage defects in rabbit knee joints with three materials and to find the best material.
METHODS: Thirty-six healthy adult New Zealand rabbits were prepared for the models of articular cartilage defects by perforating on the patellofemoral joint and randomly divided into 4 groups, with 9 animals in each group. PVA, polyurethane, and PA66 were implanted into the into articular cartilage defects in rabbits of corresponding groups. There was no treatment in the control group. The macroscopic and histological evaluations of rabbit knee joints were performed at 4, 8 and 12 weeks postoperatively. The score of histology was used to evaluate the repairs of articular cartilage defects at 12 weeks postoperatively.
RESULTS AND CONCLUSION: No infection was observed in all animals with good motion of joints. At 12 weeks postoperatively, the materials got well with surrounding cartilage, which did not degenerate obviously. The defects in the control group were filled with fibrous scar-like tissues that arranged in disorder. The histological score of the in the group implanted by PVA, as well as polyurethane, was higher than that in PA66 and the control groups (P < 0.05), but the difference between the two groups had no significance (P > 0.05). The porous materials PVA and polyurethane have good function for replacing articular cartilage, with good biocompatibility.