Effect of mesenchymal stem cells on biomechanics of stress fracture rabbit model after healing.

This study aimed to investigate the effects of mesenchymal stem cells (MSCs) on the biomechanics of stress-fractured rabbits after healing. Twenty-Four New Zealand white rabbits were selected to establish a stress fracture model. All rabbits were randomly divided into model group and MSCs group, and another 12 rabbits were chosen as control group. Compared with the control group, the mRNA expression levels of basic fibroblast growth factor (b-FGF), vascular endothelial growth factor (VEGF), osteoprotegerin (OPG) and receptor activator of nuclear factor-κ B ligand (RANKL) in the model group decreased significantly, and the OPG/RANKL ratio decreased (p<0.05). Compared with the model group, the mRNA expression levels of b-FGF, VEGF, OPG and RANKL in the MSCs group were significantly increased, and the OPG/RANKL ratio increased (p<0.05). Compared with the model group, the healing and bone mineral density in the MSCs group increased significantly (p<0.05), the biomechanical parameters (maximum load, elastic load, stiffness and maximum deflection) of the rabbits in the MSCs group were significantly improved (p<0.05). In conclusion, MSCs can significantly improve the bone mineral density of stress-fractured white rabbits; promote the release of bone formation factors and fracture healing, which can provide guidance for clinical treatment of stress fractures.