Objective: To compare the degenerative changes of adjacent segments after posterior lumbar fusion surgery using cortical bone trajectory (CBT) screws and pedicle screws (PS) in lumbar spinal degenerative disease. Methods: According to certain inclusion and exclusion criteria, prospective non-randomized study on cases of the single-segment lumbar spinal fusion surgery using cortical bone trajectory screws fixation and pedicle screws fixation in Beijing Chao-Yang Hospital from January 2015 to February 2016 was performed. The intervertebral space height (ISH), foramen height (FH), foramen width (FW), cephalad adjacent segment (CAS) and intervertebral disc degeneration grades at MRI scans were measured before surgery and during follow-up. Clinical symptoms were evaluated by Oswestry Dysfunction Index (ODI) score and pain visual analogue scale (VAS) before and during the follow-up. Radiologic adjacent segment degeneration (R-ASD) and symptomatic adjacent segment disease (S-ASD) patients were diagnosed during the follow-up. Paired sample t test was performed when data were compared before surgery and during follow-up. Results: A total of 69 patients were included in the study, 33 in the CBT group (male/female, 15/18), with an average age of (65±11) years, and 36 in the PS group (male/female, 17/19), with an average age of (64±10) years. The follow-up time was no less than 36 months. At the last follow-up, the ISH of the adjacent segments in the CBT group were not statistically different from that before surgery; the ISH of the adjacent segments in the PS group were significantly reduced compared with that before surgery (t=6.78, P<0.05). The loss of ISH, FH, and FW in the adjacent segments in the CBT group were smaller than those in the PS group, and the differences were statistically significant. During follow-up, 4 cases (12.1%) of R-ASD and no S-ASD were found in the CBT group, while 12 cases (33.3%) of R-ASD appeared in the PS group, which was significantly higher than that in the CBT group (χ(2)=4.35, P=0.04). According to MRI, the adjacent discs of PS group had significantly more severe degeneration at the last follow-up than the CBT group (Z=-2.14, P=0.03). Conclusions: Compared with the PS fixation fusion, the CBT screw fixation can effectively reduce the occurrence of adjacent segment degeneration.

目的： 比较采用皮质骨轨迹螺钉（CBT）与椎弓根螺钉（PS）进行腰椎后路减压融合手术治疗腰椎退行性疾病术后邻近节段的影像学变化，评价两种内固定方式对邻近节段的影响。 方法： 按照纳入排除标准收集2015年1月至2016年2月北京朝阳医院分别采用CBT内固定与PS内固定进行单节段腰椎后路减压融合手术治疗腰椎管狭窄症的病例资料。测量两组患者术前及随访时手术融合头侧邻近节段（CAS）椎间隙高度（ISH）、椎间孔高度（FH）、宽度（FW），术前及末次随访MRI扫描椎间盘退变分级。临床症状变化采用患者术前及随访时Oswestry功能障碍指数（ODI）评分及疼痛视觉模拟量表（VAS）评分评价，同时诊断两组影像学邻近节段退变（R-ASD）与症状性邻近节段退变（S-ASD）患者。术前、术后及随访数据比较进行配对样本t检验。 结果： 共计69例患者纳入研究，CBT组33例（男/女：15/18），年龄（65±11）岁，PS组36例（男/女：17/19），年龄（64±10）岁。末次随访时，CBT组邻近节段的ISH与术前比较差异无统计学意义；PS组邻近节段ISH较手术前显著减小（t=6.78，P<0.05）。CBT组邻近节段ISH、FH和FW的丢失程度显著小于PS组（均P<0.05）。随访期间，CBT组共发现4例（12.1%）R-ASD，无S-ASD，而PS组出现12例（33.3%）R-ASD，显著高于CBT组（χ(2)=4.35，P=0.04）。MRI显示，PS组末次随访时邻近节段椎间盘显著退变程度大于CBT组（Z=-2.14，P=0.03）。 结论： 相比于传统椎弓根螺钉内固定融合技术，单节段皮质骨螺钉内固定技术在短期内可以有效地减少邻近节段退变的发生。.