颈椎后路C3～C7椎板切除内固定融合术后中期相邻节段退变的临床研究

目的:探究脊髓型颈椎病患者施行颈椎后路C3～C7椎板切除减压，后路固定融合术后，在中期内对相邻节段退变的影响。方法:回顾性分析2015年5月—2018年5月在天津市人民医院行颈椎后路 C3～C7椎板切除减压，后路固定融合术后的41例患者。相邻节段退变的评估采取两种方式:（1）为X光影评定，即在X线侧位片上定义X线椎间隙高度丢失与术前相比大于10%；形成肉眼可见的新生骨赘或 者原有骨赘增大；或者出现前纵韧带钙化。（2）为核磁共振（MRI），在MRI T2加权像上采用Miyazaki的颈椎间盘退变分级方法观察相邻节段退变的情况。同时通过颈椎活动度及椎间高度来进行评估。 结果:所有患者均获得满意的X线片随访及MRI随访，时间为12～26个月，平均18个月。符合观察标准的节段共计82个。患者术后3 d椎间高度与术前相比差异无统计学意义（P＞0.05），末次随访与术后3 d椎间高度对比，差异无统计学意义（P＞0.05）。术后3 d与术前X线过伸、过屈位的颈椎活动度相比，颈椎活动度有明显变化，差异有统计学意义（P＜0.05），而末次随访与术后3 d对比，差异没有统 计学意义（P＞0.05）。末次随访时所有患者植骨达到骨性融合，无内固定松动、脱出、断裂发生。患者的上位、下位相邻节段未出现新生骨赘或者骨赘增大的节段、前纵韧带钙化。通过MRI影像学观察 ，末次随访、术后3 d与术前相比上位、下位相邻节段椎间盘信号无明显变化。结论:C3～C7节段行后路椎板切除减压内固定融合术后，在中期患者不会出现相邻节段退变的发生。

Clinical study on adjacent vertebral segment degeneration after posterior cervical fixation fusion at C3-C7

Objective: To investigate the effect of posterior cervical laminectomy and decompression, posterior fixation and fusion (C3-C7) on adjacent segment degeneration in patients with cervical spondylotic myelopathy in medium stage. Methods: A retrospective analysis was performed on 41 patients who underwent posterior cervical laminectomy and decompression, posterior fixation and fusion between May 2015 and May 2018 in Tianjin Union Medical Center. Two methods were used to evaluate adjacent segment degeneration. One was X-ray light and shadow evaluation. X-ray clearance height loss was defined on X-ray lateral radiographs, which was more than 10% compared with that before surgery. Formation of new osteophytes visible to the naked eye or enlargement of original osteophytes were observed. Or calcification of the anterior longitudinal ligament was assessed. Another one was MRI. Miyazaki's cervical disc degeneration grading method was used to observe the degeneration of adjacent segments on the T2-weighted MRI. Cervical range of motion and intervertebral height were also assessed. Results: All patients were followed up with satisfactory X-ray and MRI for 12-26 months, with an average of 18 months. A total of 82 segments met the observation criteria. There was no statistically significant difference in intervertebral height between 3 days after operation and preoperative(P＞0.05). And there was no statistically significant difference between the last follow-up and the postoperative 3 days(P＞0.05). There was a significantly different between 3 days after operation and preoperative X-ray of the cervical range of motion in hyperextension and hyperflexion position(P＜0.05). And there was no significantly different between postoperative 3 days and the last follow-up X-ray of the cervical range of motion in hyperextension and hyperflexion position(P＞0.05). At the last follow-up, all the patients were bone grafted to achieve osseous fusion, and no internal fixation looseness, prolapse or fracture occurred. There was no calcification of new osteophytes or enlarged segments of the anterior longitudinal ligament in the upper and lower adjacent segments of the patient.According to the observation of MRI imaging, there was no significant change in the signal of upper and lower adjacent segment intervertebral discs at the last follow-up and 3 days after operation compared with preoperative. Conclusion: Adjacent segment degeneration does not observe after posterior cervical laminectomy decompression and fixation fusion (C3-C7) in medium stage.