椎体融合经皮椎弓根钉内固定术后邻近节段退行性变的发病机制

A study on degeneration of adjacent vertebra after pedicle screw fixation for vertebral fusion

目的分析椎弓根钉内固定术患者邻近节段退行性变(adjacent segment degeneration,ASD)的发生特点,探索其发病机制。方法选取2010-01至2013-12因脊柱疾病在接受手术治疗的患者72例为研究对象,均接受MRI和X线正、侧位检查,根据诊断标准计算ASD的发生率。分别采用视觉模拟评分法(VAS)和Oswestry功能障碍指数问卷表(ODI)对患者的疼痛和功能障碍情况进行评估。结果本组ASD发生率为26.39%。术前疼痛感明显,多种活动功能因疼痛而受到影响,VAS评分为5.20±1.19,ODI评分为0.43±0.12;末次随访时VAS评分为2.11±0.82,ODI评分为0.22±0.08,术前术后比较差异均有统计学意义(P<0.001)。结论椎弓根钉内固定术是引起ASD的原因之一,其机制可能与手术改变了邻近节段的受力和活动度变化有关。

Objective To study the occurrence of adjacent segment degeneration in patients who underwent pedicle screw fixation,and further inquire into the pathogenesis of adjacent segment degeneration. Methods Seventy-two patients with spinal diseases underwent surgical treatment in this hospital from January 2010 to December 2013 were recruited as the study objects,all the patients underwent MRI and X ray examination,the ASD was diagnosed according to the findings of MRI and X-rays,the incidence of ASD was calculated. Visual analog scale（ VAS） and Oswestry disability index questionnaire（ ODI） were used to assess the pain and functional disability of patients. Results The incidence of ASD was 26. 39%. The preoperative pain was significant and a variety of activity functions were affected by pain before the treatment,VAS score was 5. 20 ± 1. 19,ODI score was 0. 43 ± 0. 12. At the last follow-up,VAS score was 2. 11 ± 0. 82,ODI score was 0. 22 ± 0. 08,there was statistically significant difference between preoperative and postoperative scores（ P〈0. 05）. Conclusions Pedicle screw fixation can induce the occurrence of adjacent segment degeneration. The mechanism may be related to changes of pressure and activity degree of the adjacent segment.