Experimental study of biologically active icariin combined with a porous PLGA/TCP scaffold to repair cartilage and subchondral bone in articular cartilage defect in rabbits

In this study, we designed a porous PLGA/TCP scaffold to carry and slowly release biologically active icariin, then observed the effect of the scaffold on the integral repair of articular cartilage defect in rabbits. We used New Zealand white rabbits to establish an articular cartilage defect animal model with a 5 mm diameter by 4 mm depth defect in the femoral intercondylar fossa. Gross specimen scores, Mankin scores, HE staining, AB-PAS staining, Safranin O staining, immunohistochemical staining of type II collagen, and CT scans were used to evaluate the repair conditions 6 months after the model was established. The result showed that there were more chondrocytes, matrix, and type II collagen around and covering the defect and the subchondral bone was in better shape in the bioactive icariin porous PLGA/TCP scaffolds repairing group. CT scans showed that the trabecular bone structure was intact. Gross specimens and Mankin scores were significantly lower. These findings suggested that the use of bioactive icariin porous PLGA/TCP scaffolds promoted the integral repair of articular cartilage defect from the cartilage to the subchondral bone.