RESUMO
OBJECTIVES: This study aims to investigate the changes in bone morphogenetic protein-2 (BMP-2) expression and mechanical properties in the healing process of rats with osteoporotic hindlimb fracture. METHODS: 120 rat models of osteoporotic hindlimb fracture were established and randomly divided into experimental group and control group. Quantitative real-time polymerase chain reaction (PCR) used to detect the BMP-2 expression in the rat's callus tissue on the fractured side. The mechanical properties of rat's hindlimb skeleton were examined using a universal material mechanics testing machine. RESULTS: The BMP-2 expression in the experimental group was higher than that in the control group (p<0.05). The linear correlation analysis showed that the BMP-2 was positively correlated with healing time (r=0.87, p<0.05). The mechanical properties were markedly improved at T2, T3 and T4, which peaked at T4 (p<0.05). However, the mechanical properties in the rats in the experimental group were notably superior to those in the control group at T2, T3, and T4 (p<0.05). CONCLUSIONS: The treatment with strontium ranelate can effectively improve the BMP-2 and bone mechanical properties of the rats with osteoporotic hindlimb fracture in the healing stage and accelerate the healing progress, which could be proved to be an efficacious means in treating osteoporotic fracture.