Experimental Study on the Treatment of Femur Head Necrosis with Tricalcium Phosphate and Platelet-Rich Plasma

Background: To study the mechanism of compound of calcium phosphate (TCP) and platelet-rich plasma(PRP) in the treatment of femoral head necrosis.

Methods: The left femoral heads of 48 New Zealand white rabbits were frozen by liquid nitrogen as to make the model of femoral head necrosis. Twenty-four rabbits were randomly chosen as the experimental group and their femoral heads were filled with TCP/PRP. The other 24 rabbits were used as the control group and their femoral heads were filled only with TCP. They were sacrificed at 2, 4, 8, 12 weeks after operation. The specimens were examined with X-ray and histological study.

Results: At 2 weeks after operation, there was no significant difference in femoral head density between the two groups. Four weeks after operation, femoral head density decreased in both groups, while it decreased more in the control group. At 8, 12 weeks after operation, the density of the femoral heads in both groups increased, and it was higher in the experimental group. Histology examination showed that there was no difference between the two groups 2 weeks after operation. The head became flat at 4 weeks. Control group had more defects. At 4, 8, 12 weeks, more repairs were observed in the experimental group than that in the control group. The amount and maturity of osteogenesis in experimental group were much more greater than those in control group. Bone histomorphometry showed that the volume of the trabecular was larger in the experimental group (36.65% +/- 7.22%, 38.29% +/- 4.28%, 39.24% +/- 3.42%) than that of control group (P < 0. 05).

Conclusion: TCP/PRP does not only provide osteoblasts scaffold, but also promotes bone formation and the head repair. TCP/PRP is a good biomaterial for the treatment of femur head necrosis.