Ninomiya Koshi, Iwatsuki Koichi, Ohnishi Yu-Ichiro, Ohkawa Toshika, Yoshimine Toshiki
Department of Neurosurgery, Osaka University Graduate School of Medicine, Suita, Japan.
Asian Spine J. 2016 Oct;10(5):901-906. doi: 10.4184/asj.2016.10.5.901. Epub 2016 Oct 17.
Retrospective study.
Cortical bone trajectory (CBT), a more medial-to-lateral and shorter path than the traditional one for spinal fusion, is thought to be effective for severely degenerated vertebrae because screws are primarily stabilized at the posterior elements. We evaluated the efficacy of this approach through insertional torque measurement.
There has been only one prior study on CBT insertional torque.
Between January 2013 and April 2014, a total of 22 patients underwent posterior lumbar fusion using the CBT technique. The maximum insertional torque, which covers the radial strength needed for insertion, was measured for 113 screws, 8 of which were inserted for L5 spondylolysis. The insertional torque for cases with (n=8) and without (n=31) spondylolysis of L5 were compared using one-way analysis of variance (ANOVA). To evaluate vertebral degeneration, we classified 53 vertebrae without spondylolysis by lumbar radiography using semiquantitative methods; the insertional torque for the 105 screws used was compared on the basis of this classification. Additionally, differences in insertional torque among cases grouped by age, sex, and lumbar level were evaluated for these 105 screws using ANOVA and the Tukey test.
The mean insertional torque was significantly lower for patients with spondylolysis than for those without spondylolysis (4.25 vs. 8.24 in-lb). There were no statistical differences in insertional torque according to vertebral grading or level. The only significant difference in insertional torque between age and sex groups was in men <75 years and women ≥75 years (10 vs. 5.5 in-lb).
Although CBT should be used with great caution in patient with lysis who are ≥75 years, it is well suited for dealing with severely degenerated vertebrae because the pars interarticularis plays a very important role in the implementation of this technique.
回顾性研究。
皮质骨轨迹（CBT），一种比传统脊柱融合路径更靠近内侧且更短的路径，被认为对严重退变的椎体有效，因为螺钉主要固定于后部结构。我们通过插入扭矩测量评估了该方法的疗效。
此前仅有一项关于CBT插入扭矩的研究。
在2013年1月至2014年4月期间，共有22例患者采用CBT技术进行了后路腰椎融合术。测量了113枚螺钉的最大插入扭矩，其中8枚用于L5峡部裂的植入。采用单因素方差分析（ANOVA）比较L5有峡部裂（n = 8）和无峡部裂（n = 31）病例的插入扭矩。为评估椎体退变情况，我们采用半定量方法通过腰椎X线摄影对53例无峡部裂的椎体进行分类；根据该分类比较所使用的105枚螺钉的插入扭矩。此外，对这105枚螺钉，采用ANOVA和Tukey检验评估按年龄、性别和腰椎节段分组的病例之间插入扭矩的差异。
峡部裂患者的平均插入扭矩显著低于无峡部裂患者（4.25 vs. 8.24英寸磅）。根据椎体分级或节段，插入扭矩无统计学差异。年龄和性别组之间插入扭矩的唯一显著差异在于年龄＜75岁的男性和年龄≥75岁的女性（10 vs. 5.5英寸磅）。
尽管对于年龄≥75岁且有峡部裂的患者应极其谨慎地使用CBT，但它非常适合处理严重退变的椎体，因为关节突间部在该技术的实施中起着非常重要的作用。
