Abstract: Objective To study the biomechanic characteristics of knee joint after cartilage repairing with platelet-rich plasma( PRP). Methods The models of cartilage injury on weight-bearing area in the medial femoral were constructed,and were respectively repaired by PRP and normal saline ( NS). The uninjured cartilages were regarded as control group. The repair of injured cartilage were examined,and the medial and lateral contact area and pressure of the knee joint were recorded 1,3,5 weeks postoperatively. Results The newly repaired cartilage was observed in PRP group,and the reparative effect was better than the NS group 1,3,5 weeks postoperatively. There were no significant difference in the fields of the contact area and pressure of the medial and lateral the tibiofemoral joint five weeks after operation between the PRP group and the control group( P>0 . 05 ). Conclusion The PRP was a potential factor for repairing injured cartilage. The contact area and pressure of the knee joint after repair by PRP were similar to the normal cartilage.

Key words: cartilage, articular, platelet rich plasma, reconstructive surgical procedures