Janevic J, Ashton-Miller J A, Schultz A B
Department of Mechanical Engineering and Applied Mechanics, University of Michigan, Ann Arbor 48109.
J Orthop Res. 1991 Mar;9(2):228-36. doi: 10.1002/jor.1100090211.
The bending, shear, and torsion flexibilities of 13 intact adult lumbar motion segments (from 11 men, two women, 48-83 years of age) were compared under three different compressive preloads, 0, 2,200, and 4,400 N. Test forces and moments up to 160 N and 16 Nm were applied at the center of the upper end plate of the intact disc. A compressive preload of 2,200 N resulted in a significant decrease in motion segment flexibilities in all seven test directions (p less than 0.06) when compared with results obtained with no preload; the preload decreased flexibility 2.6, 4.5, and 6.1 times in bending, axial torsion, and shear, respectively. These results suggest that studies of internal trunk load-sharing between active and passive tissues during strenuous tasks, which engender large spine compressive loads, should take these changes in spine passive resistance into consideration.
对13个完整的成人腰椎运动节段（来自11名男性和2名女性，年龄在48至83岁之间）在三种不同的压缩预载荷（0、2200和4400 N）下的弯曲、剪切和扭转柔韧性进行了比较。在完整椎间盘上端板中心施加高达160 N和16 Nm的测试力和力矩。与无预载荷时的结果相比，2200 N的压缩预载荷导致所有七个测试方向上的运动节段柔韧性显著降低（p小于0.06）；预载荷使弯曲、轴向扭转和剪切的柔韧性分别降低了2.6倍、4.5倍和6.1倍。这些结果表明，在剧烈任务期间，主动组织和被动组织之间内部躯干负荷分担的研究，会产生较大的脊柱压缩负荷，应考虑脊柱被动阻力的这些变化。
