Fig. 1. Operation process of the establishment of rabbit model by liquid nitrogen freezing. (A) Blunt separation of the gluteus maximus muscle, gluteus medius muscle, and gluteus minimus muscle. (B) Dislocation of femoral head and covering it with a rubber funnel. (C) Freezing the femoral head with liquid nitrogen by medical cotton stickers. (D) Drilling a 5 mm-depth hole at an angle of 45° from the posteromedial femoral neck according to the direction of the arrow until the bit arrived at the underside of articular cartilage. (E) Injection of PBMSCs of passage 2 or passage 3 after drilling. (F) Suture of the wound layer by layer. (G) Direction of the drilling. PBMSCs, peripheral blood-derived mesenchymal stem cells.
