Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada.
Centre for Comparative and Clinical Anatomy, University of Bristol, Bristol, United Kingdom.
Global Spine J. 2015 Oct;5(5):360-5. doi: 10.1055/s-0035-1546956. Epub 2015 Feb 25.
Study Design Biomechanical study on cadaveric spines. Objective Spinal bending causes the annulus to pull vertically (axially) on the end plate, but failure mechanisms in response to this type of loading are poorly understood. Therefore, the objective of this study was to identify the weak point of the intervertebral disk in tension. Methods Cadaveric motion segments (aged 79 to 88 years) were dissected to create midsagittal blocks of tissue, with ∼10 mm of bone superior and inferior to the disk. From these blocks, 14 bone-disk-bone slices (average 4.8 mm thick) were cut in the frontal plane. Each slice was gripped by its bony ends and stretched to failure at 1 mm/s. Mode of failure was recorded using a digital camera. Results Of the 14 slices, 10 failed by the hyaline cartilage being peeled off the subchondral bone, with the failure starting opposite the lateral annulus and proceeding medially. Two slices failed by rupturing of the trabecular bone, and a further two failed in the annulus. Conclusions The hyaline cartilage-bone junction is the disk's weak link in tension. These findings provide a plausible mechanism for the appearance of bone and cartilage fragments in herniated material. Stripping cartilage from the bony end plate would result in the herniated mass containing relatively stiff cartilage that does not easily resorb.
研究设计 尸体脊柱的生物力学研究。目的 脊柱弯曲会导致纤维环沿垂直方向（轴向）牵拉终板，但对于这种类型的负载的失效机制知之甚少。因此，本研究的目的是确定椎间盘在拉伸下的弱点。方法 对尸体运动节段（年龄 79 至 88 岁）进行解剖，以创建中矢状组织块，椎间盘上下有 ∼10mm 的骨。从这些块中，在额状面切割了 14 个骨-椎间盘-骨切片（平均 4.8mm 厚）。每个切片的骨端被夹住，并以 1mm/s 的速度拉伸至失效。使用数码相机记录失效模式。结果 在 14 个切片中，有 10 个由于透明软骨从软骨下骨上剥落而失效，失效始于纤维环的外侧，并向内侧进展。两个切片由于小梁骨破裂而失效，另外两个在纤维环处失效。结论 透明软骨-骨交界处是椎间盘在拉伸下的弱点。这些发现为椎间盘突出物中出现骨和软骨碎片提供了一个合理的机制。从骨终板上剥离软骨会导致椎间盘突出物包含相对坚硬的软骨，不易吸收。
