基于超声共振谱的坐骨神经离断术后兔皮质骨细观力学特性测量

Objective The effect of sciatic neurectomy (SN) on the meso-mechanical properties of cortical bone was explored by combining animal modeling and resonant ultrasound spectroscopy. Methods A total of five New Zealand White rabbits underwent unilateral SN, and cortical bone specimens were obtained from the tibias on the operated and normal sides at 4^th week after SN; multiple elastic constants (C₁₁, C₁₂, C₁₃, C₃₃, and C₄₄ ), engineering mechanical parameters, and anisotropy ratios of the bone specimens were acquired using irregular resonant ultrasound spectroscopy under assumptions of transverse anisotropy, and the paired t-test was used to assess the differences in mechanical properties of the cortical bone between the two sides. Results Compared with the normal side, the elastic constants in different directions (C₁₁, C₁₂, C₁₃, and C₃₃) of the cortical bone on the operated side showed a decreasing trend, ranging from 8. 49% to 32. 23%; the axial elastic modulus (E₃) and Poisson’s ratio (v₃₁) were reduced by 5. 85% and 24. 07%, respectively, but there were no significant changes in the anisotropic properties. Conclusions The method of cortical bone disuse modeling through SN is feasible. This method can significantly change meso-mechanical properties of the cortical bone, and the elastic constants can more comprehensively reflect the changes in mechanical properties of the cortical bone.