Raynor R B, Pugh J, Shapiro I
J Neurosurg. 1985 Aug;63(2):278-82. doi: 10.3171/jns.1985.63.2.0278.
Fourteen cervical spine motion segments consisting of two adjacent vertebral bodies and their connecting ligaments were tested in shear. Five had intact facet joints, five had bilateral facetectomy of 50% or less, and four had bilateral 70% facetectomy. Three to 5 mm of root could be exposed in the specimens with 50% facetectomy, and 8 to 10 mm in those with 70% facetectomy. Anterior-posterior shear tests were run alternately in compression and distraction. Facetectomy was found to have no effect on compression and distraction stiffness. Failure in the 70% facetectomized specimens was due to fracture of the remaining joint at 159 lbs. In the specimens with 50% facetectomy, a fracture load could not be established since failure of the specimen mounting occurred at 208 lbs, as it did in two of the specimens without facetectomy that were tested to failure. The difference in bone fracture at 159 lbs and mounting failure at 208 lbs is significant at p less than 0.05. Bilateral resection of more than 50% of the facet joint significantly compromises the shear strength of a cervical spine motion segment.
对由两个相邻椎体及其连接韧带组成的14个颈椎运动节段进行了剪切测试。其中5个节段的小关节完整，5个节段进行了双侧小关节切除术，切除比例为50%或更低，4个节段进行了双侧70%的小关节切除术。在50%小关节切除的标本中可暴露3至5毫米的神经根，在70%小关节切除的标本中可暴露8至10毫米的神经根。前后剪切测试在压缩和牵张状态下交替进行。发现小关节切除术对压缩和牵张刚度没有影响。70%小关节切除的标本在159磅时因剩余关节骨折而失效。在50%小关节切除的标本中，由于标本固定在208磅时失效，无法确定骨折负荷，未进行小关节切除的两个测试至失效的标本也是如此。159磅时的骨折与208磅时的固定失效之间的差异在p小于0.05时具有显著性。双侧切除超过50%的小关节会显著损害颈椎运动节段的剪切强度。
