Shah J S, Hampson W G, Jayson M I
J Bone Joint Surg Br. 1978 May;60-B(2):246-51. doi: 10.1302/0301-620X.60B2.659474.
The fourth lumbar vertebrae and L4-5 discs from six cadaveric lumbar spines were subjected to detailed strain gauge analysis under conditions of controlled loading. With central compression loads, maximal compressive strain was found to occur near the bases of the pedicles and on both superficial and deep surfaces of the pars interarticularis, which emphasises the importance of the posterior elements of lumbar vertebrae in transmitting load. Radial bulge and tangential strain of the disc wall were maximal at the posterolateral surface, in agreement with the fact that disc degeneration and prolapse commonly occur there. Under posterior offset loads simulating extension, both compressive and tensile strains were found to be increased on both surfaces of the pars interarticularis, which suggests that hyperextension may lead to stress fractures and spondylolisthesis. Posterior offset loads also increased the radial bulge of the posterior disc wall and tangential strain at the anterior surface of the disc. Anterior offset loads simulating flexion increased the radial bulge of the anterior disc wall and tangential strain at the posterior surface of the disc. These findings are compatible with movement of the nucleus pulposus within the disc during flexion and extension. This hypothesis was supported by post-mortem discography.
对六具尸体腰椎的第四腰椎椎体和L4 - 5椎间盘在可控加载条件下进行了详细的应变片分析。在中心压缩载荷作用下，最大压缩应变出现在椎弓根基部附近以及关节突间部的浅面和深面，这强调了腰椎后部结构在传递载荷中的重要性。椎间盘壁的径向膨出和切向应变在椎间盘后外侧表面最大，这与椎间盘退变和突出通常发生在该部位的事实相符。在模拟伸展的后向偏移载荷作用下，关节突间部两面的压缩应变和拉伸应变均增加，这表明过伸可能导致应力性骨折和椎体滑脱。后向偏移载荷还增加了椎间盘后壁的径向膨出和椎间盘前表面的切向应变。模拟屈曲的前向偏移载荷增加了椎间盘前壁的径向膨出和椎间盘后表面的切向应变。这些发现与屈伸过程中髓核在椎间盘内的移动情况相符。这一假设得到了尸体椎间盘造影的支持。
