Chow Daniel H K, Luk Keith D K, Holmes Andrew D, Li Xing-Fei, Tam Steven C W
Jockey Club Rehabilitation Engineering Centre, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, PR China.
Clin Biomech (Bristol). 2004 Feb;19(2):99-106. doi: 10.1016/j.clinbiomech.2003.11.001.
To assess the changes in the multi-planar bending properties of intervertebral joints following cyclic bending along different directions.
An in vitro biomechanical study using porcine lumbar motion segments.
Repeated bending has been suggested as part of the etiology of gradual prolapse of the intervertebral disc, but the multi-planar changes in bending properties following cyclic loading have not been examined in detail.
Porcine lumbar motion segments were subject to 1500 cycles of bending along directions of 0 degrees (flexion), 30 degrees, 60 degrees, or 90 degrees (right lateral bending). The multi-planar bending moments and hysteresis energies were recorded before loading and after various cycle numbers.
Repeated bending at 30 degrees and 60 degrees resulted in greater decreases in mean bending moment and hysteresis energy than bending at 0 degrees or 90 degrees. No significant differences were seen between loading groups for the change in bending moment along the anterior testing directions, but significant differences were observed in the posterior and lateral testing directions, with bending at 30 degrees causing a significantly greater decrease in bending moment in the postero-lateral directions.
The change in mechanical properties of porcine intervertebral joints due to cyclic bending depend on the direction of loading and the direction in which the properties are measured. Loading at 30 degrees provokes the most marked changes in bending moment and hysteresis energy.
评估沿不同方向进行周期性弯曲后椎间关节多平面弯曲特性的变化。
使用猪腰椎运动节段进行的体外生物力学研究。
反复弯曲被认为是椎间盘逐渐脱垂病因的一部分，但循环加载后弯曲特性的多平面变化尚未得到详细研究。
猪腰椎运动节段沿0度（前屈）、30度、60度或90度（右侧弯）方向进行1500次弯曲循环。在加载前和不同循环次数后记录多平面弯矩和滞后能量。
与0度或90度弯曲相比，30度和60度的反复弯曲导致平均弯矩和滞后能量的下降更大。在前侧测试方向上，各加载组之间弯矩变化无显著差异，但在后侧和外侧测试方向上观察到显著差异，30度弯曲在后外侧方向上导致弯矩显著更大的下降。
猪椎间关节因周期性弯曲而产生的力学性能变化取决于加载方向和测量性能的方向。30度加载引起弯矩和滞后能量最明显的变化。
