MRI辅助髓核容积测量评价ISOBAR TTL动态内固定系统对固定节段邻近椎间盘退变影响的临床研究

INFLUENCE OF ISOBAR TTL DYNAMIC INTERNAL FIXATION SYSTEM ON ADJACENT SEGMENT DEGENERATION BY MRI MEASUREMENT OF LUMBAR NUCLEUS PULPOSUS VOLUME

目的探讨运用MRI检查测量固定节段邻近椎间盘髓核容积的变化,来研究ISOBAR TTL动态内固定系统对固定节段邻近椎间盘退变的影响。方法回顾分析2010年3月-2011年10月,采用ISOBAR TTL动态内固定系统手术治疗的34例单节段腰椎间盘突出症患者临床资料。男20例,女14例;年龄39～62岁,平均47.5岁。病程6～18个月,平均14个月。病变节段：L4、5 21例,L5、S1 13例。腰椎间盘突出症类型：旁中央型23例、外侧型11例。术前及术后6、12、18、24、36、48个月常规行X线片及MRI检查,采用角平分线法测量固定节段头侧邻近椎间隙高度,MRI辅助髓核容积测定法测量固定节段头侧邻近髓核容积。比较手术前后邻近节段椎间隙高度及髓核容积,评价Isobar TTL动态内固定技术对固定节段头侧邻近椎间盘退变的影响。结果术后30例获随访,均随访至48个月。手术前后各时间点间比较邻近节段椎间隙高度差异均无统计学意（P〉0.05）;术后6、12、18个月的邻近节段髓核容积与术前比较差异无统计学意义（P〉0.05）,但术后24、36、48个月的邻近节段髓核容积显著高于术前（P〈0.05）。髓核容积各数值中,术后6、12、18个月髓核高度及宽度与术前比较差异无统计学意义（P〉0.05）,但术后24、36、48个月髓核高度较术前增大,髓核宽度较术前减少,差异均有统计学意义（P〈0.05）;术后18、24、36、48个月髓核前后径均高于术前,比较差异有统计学意义（P〈0.05）。结论 ISOBAR TTL动态内固定系统对固定节段邻近椎间盘退变有一定预防或延迟其退变的作用。

Objective To investigate the influence of ISOBAR TTL dynamic internal fixation system on degeneration of adjacent intervertebral disc by MRI measurement of lumbar nucleus pulposus volume in treating lumbar degenerative disease after operation. Methods Between March 2010 and October 2011, 34 patients with lumbar intervertebral disc herniation（23 cases of paracentral type and 11 cases of lateral type） underwent operation with ISOBAR TTL dynamic internal fixation system for fixation of single segment, and the clinical data were analyzed retrospectively. There were 20 males and 14 females, aged 39-62 years（mean, 47.5 years）. The disease duration was 6-18 months（mean, 14 months）. Involved segments included L4, 5 in 21 cases and L5, S1 in 13 cases. The X-ray films and MRI images were taken at 6, 12, 18, 24, 36, and 48 months after surgery. Based on X-ray films, the height of intervertebral space was measured using angle bisectrix method. The nucleus pulposus volume was measured based on the MRI scan. The postoperative change of nucleus pulposus volume and intervertebral disc height were used to evaluate the influence of ISOBAR TTL system on degeneration of adjacent intervertebral disc nucleus pulposus. Results Thirty patients were followed up 48 months. The height of intervertebral space showed no significant difference between at pre- and post-operation（P〉0.05）. The nucleus pulposus volume increased after operation, showing no significant difference at 6, 12, and 18 months when compared with preoperative value（P〈0.05）, but significant difference was found at 24, 36, and 48 months when compared with preoperative value（P〈0.05）. The height of nucleus pulposus increased after operation but the width was decreased; the values showed no significant difference at 6, 12, and 18 months when compared with preoperative ones, but showed significant difference at 24, 36, and 48 months when compared with preoperative ones（P〈0.05）. The diameter of nucleus pulposus at 18, 24, 36, and 48 months after operation was significantly langer than that at preoperation（P〈0.05）. Conclusion ISOBAR TTL dynamic internal fixation system can prevent or delay the degeneration of intervertebral discs.