Various animal models and clinical trials show that the recombinant human bone morphogenetic protein (rhBMP) has the capacity of bone induction.OBJECTIVE:
To study the effect of glue-like E-matrix as a new type of carrier for rhBMP-2 on posterolateral spinal fusion of rats.METHODS:
Posterolateral fusion models were established in 105 male Lewis rats. Absorbable gelatin sponge and rhBMP-2 with different qualities were implanted into the L4-5 intertransverse of rats under the same conditions. Observation of adding glue-like E-matrix or not into groups was performed.RESULTS AND CONCLUSIONS:
Fusion rates of the rats with 10 μg rhBMP-2 and 3 μg rhBMP-2 were 100%, and those of the rats with 1 μg, 0.5 μg and 0.1 μg of rhBMP-2 were 40%, 10% and 0% respectively. In the adding glue-like E-matrix groups, the fusion rate of rats with > 0.5 μg rhBMP-2 was 100%, but no fusion was observed in the rats with 0.1 μg and 0.05 μg rhBMP-2. The micro-CT results revealed that the amount of the new bone created in the 10 μg rhBMP-2 + E-matrix group and the 3 μg rhBMP-2+E-matrix group were similar. However, there was no new bone created in the 0.1 μg and 0.05 μg rhBMP-2 groups containing E-matrix or not. E-matrix can enhance the fusion rate of rhBMP-2 significantly in posterolateral spinal fusion. However, the expected fusion cannot be achieved by E-matrix if the dose of rhBMP-2 is too small.