人工腰椎间盘置换术与椎间融合术的生物力学仿真

利用有限元法评估人工腰椎间盘置换术与椎间融合术的生物力学效果.基于CT图像数据建立腰椎L2~L5节段有限元模型，并在此基础上建立人工腰椎间盘置换和椎间融合2种手术模型.对有限元模型施加模拟生理载荷，计算两种手术模型各节段椎间活动度和小关节接触应力.仿真结果表明:相比椎间融合术，人工腰椎间盘置换术在手术节段产生了明显的运动保留功能，但置换节段在后伸和侧弯工况下活动度比正常腰椎增大40.9%和43.1%，易引起手术节段的轻度失稳;人工间盘置换术改善了上下邻近节段小关节的受力状态，但置换节段在扭转工况下会引发较高的小关节接触应力.

Biomechanical Simulation of Artificial Lumbar Intervertebral Disc Replacement and Intervertebral Fusion

The finite element method was used to evaluate the biomechanical effects of artificial lumbar intervertebral disc replacement and intervertebral fusion. Based on the CT image data， a finite element model of lumbar segments L2~L5 was established， and two kinds of surgical models of artificial lumbar disc replacement and intervertebral fusion were established. The simulated physiological load was applied to the finite element model， and the intervertebral activity and facet joint stress of each segment of the two surgical models were calculated. The simulation results showed that artificial lumbar disc replacement has a significant motion preservation in the surgical segment compared with intervertebral fusion，but the range of motion(ROM)were 40.9% and 43.1% higher than that of the normal lumbar in extension and lateral bending， which may cause mild instability of the surgical segment. Artificial disc replacement improves the stress state of the small joints of the upper and lower adjacent segments， but the replacement segment will induce higher contact pressure of the small joints under torsional conditions.