Hukins D W
Department of Medical Biophysics, University of Manchester, U.K.
Proc Biol Sci. 1992 Sep 22;249(1326):281-5. doi: 10.1098/rspb.1992.0115.
The nucleus pulposus of the intervertebral disc exerts a pressure which enables it to support axial compression when contained by the annulus fibrosus. The disc was modelled as a thick-walled cylindrical pressure vessel in which the nucleus was contained radially by the annulus. As a result, the stress in the annulus had radial (compressive) as well as tangential (tensile) components. The radial stress at a given point in the annulus was considered to be balanced by the internal pressure which is expected to arise from the attraction of water by proteoglycans. There was a reasonable agreement between the calculated radial stress distribution and published results on the distribution of water within the annulus. As the internal pressure is expected to be isotropic, the annulus was expected to contribute to the axial resistance to compression of the disc; this contribution would be equal, in magnitude, to the radial stress. Predictions of the pressure distribution within the annulus were similar to published experimental measurements made in the radial and axial directions. The tangential stress within the annulus was considered to arise from the restoring stress in its strained collagen fibrils.
椎间盘的髓核施加一种压力，当它被纤维环包裹时，这种压力使其能够承受轴向压缩。椎间盘被模拟为一个厚壁圆柱形压力容器，其中髓核被纤维环径向包裹。因此，纤维环中的应力既有径向（压缩）分量，也有切向（拉伸）分量。纤维环中某一给定点的径向应力被认为由蛋白聚糖对水的吸引所产生的内压平衡。计算得到的径向应力分布与已发表的关于纤维环内水分布的结果之间存在合理的一致性。由于预期内压是各向同性的，因此预计纤维环会对椎间盘的轴向抗压性有所贡献；这种贡献在大小上与径向应力相等。对纤维环内压力分布的预测与已发表的在径向和轴向上进行的实验测量结果相似。纤维环内的切向应力被认为是由其应变胶原纤维中的恢复应力产生的。
