Joint cartilage experimental defect regeneration by hierarchic biphasic combined grafts

Background: The existing surgical techniques used to regenerate articular cartilage fail. Utilisation of hierarchical, biphasic structures obtained from osteochondral tissue, through demineralisation, decellularization, longitudinal perforation and combination with chondroprogenitor cells, presents a high potential in cartilage defects regeneration. Material and methods: The research was performed on 36 rabbits, separated equally in two experimental and one control group. In the experimental groups, the experimental osteochondral defects of 4-4.5 mm in depth, were performed with a 3.7 drill bit at the level of weight bearing surface of the medial femoral condyle. In the 1st group the defects were treated with grafts combined with autologous chondrocytes, and in the 2nd group with grafts combined with autologous mesenchymal stem cells. In the control group, cartilaginous defects were treated by transferring the osteochondral plugs taken from the trochlear groove. The rabbits were removed from the experiment at 6 and 12 weeks. The results were evaluated by Unified Histological Score of Regenerated Cartilage (UHSRC). Results: At 6 weeks, according to UHSRC, the 1st group had 28.33±1.53 points, the 2nd group –27.67±2.08 points and the control group –26.33±1.53 points (p˃0.1; p˃0.2). At 12 weeks the 1st group had 18.68±5 points, the 2nd group –14.89±3.76 points and the control group –17.22 ±4.84 points (p˃0.5; p˃0.2). Conclusions: According to UHSRC, the experimental groups don’t show a significant difference compared to the control group at 6 and 12 weeks, also the quality of regenerated cartilage is poor.