后路间接减压治疗不同椎管侵占率的胸腰椎爆裂骨折的效果观察

Comparative study on the treatment outcome of indirect decompression in thoracolumbar burst fractures with an intact posterior longitudinal ligament but different ratios of spinaspinal canal encroachmentl

背景:胸腰椎爆裂骨折突入椎管的骨块可通过韧带复位技术间接复位椎管减压,但椎管被侵占至何种程度可采用韧带复位存在争议,而目前对较高椎管侵占率病例韧带复位的效果报道较少。目的目的:比较后纵韧带连续、椎管侵占率不同的胸腰椎爆裂骨折患者行后路间接椎管减压治疗的临床及影像学结果。方法方法:回顾性分析2010年6月至2014年6月收治的后纵韧带连续的胸腰椎爆裂骨折患者175例,按术前椎管侵占程度不同分为两组。低侵占率组:术前椎管侵占率<50%,高侵占率组:术前椎管侵占率≥50%。比较两组ASIA分级、伤椎后凸Cobb角、椎体压缩率、术后椎管侵占率。同时观察高侵占率组手术前后影像学结果的变化。结果结果:两组术前ASIA分级差异有统计学意义(P<0.05),但术后ASIA分级差异无统计学意义(P>0.05)。术前低侵占率组的伤椎后凸Cobb角、椎体压缩率、椎管侵占率分别为28.18°±12.00°、35.68%±10.72%、36.68%±6.75%;高侵占率组分别为36.64°±10.85°、52.50%±12.20%、63.57%±11.33%;两组比较差异有统计学意义(P<0.05)。术后低侵占率组的伤椎后凸Cobb角、椎体压缩率、椎管侵占率分别为5.95°±2.75°、6.41%±3.19%、11.59°±5.99%;高侵占率组的上述三个值分别为7.00°±3.88°、8.21%±3.49%、15.79%±6.70%,两组比较差异无统计学意义(P>0.05)。同时,高侵占率组的上述三个参数手术前后比较差异有统计学意义(P<0.001)。结论结论:对后纵韧带连续的胸腰椎骨折,椎管侵占率≥50%的高侵占率患者也可应用韧带复位技术行后路间接减压手术,后纵韧带的完整性可作为后路间接减压的指征之一。

Background： It has been approved that indirect reduction can be performed by the ligamentotaxis in thoracolumbar burst fractures with retropulsed fragments in spinal canal. But there is controversy on the application of the ligamentotaxis how degree spinal canal encroachment is. And there are few reports on clinical outcome of indirect decompression in high-de-gree of spinal canal encroachment after thoracolumbar burst fractures. Objective：To compare the clinical and radiological results of posterior indirect decompression in patients with a high or low ratio of spinal canal encroachment after thoracolumbar burst fractures with an intact posterior longitudinal ligament. Methods：One hundred and seventy-five thoracolumbar burst fracture patients with an unworn posterior longitudinal liga-ment, who were treated by posterior indirect decompression in our hospital from June 2010 to June 2014 were selected in this retrospective study. They were divided into two groups according to different spinal canal encroachment ratios：low en-croachment group （ratio〈50%） and high encroachment group （ratio≥50%）. The pre-and postoperative clinical and radiolog-ical results such as ASIA grading, Cobb angle, anterior vertebral height compression ratio and spinal canal encroachment ra-tio were evaluated and compared between two groups. Preoperative radiological results of the high encroachment group were compared with postoperative ones. Results：There was significant difference in preoperative ASIA grading between the two groups （P〈0.05）, but no significant difference was found in postoperative one （P〉0.05）. Preoperative Cobb angle, anterior vertebral height compression rateand canal encroachment ratio were 28.18° ± 12.00° , 35.68%± 10.72%and 36.68%± 6.75%in the low encroachment group, and 36.64°±10.85, 52.50%±12.20%and 63.57%±11.33%in the high encroachment group. There were significant differenc-es in the above-mentioned parameters between the two groups （P〈0.05）. Postoperative Cobb angles, anterior vertebral height compression rate and canal encroachment ratio were 5.95°±2.75°, 6.41%±3.19%and 11.59%±5.99%in the low en-croachment group, and 7.00°±3.88°, 8.21%±3.49%and 15.79%±6.70%in the high encroachment group. There was no sig-nificant difference in the above-mentioned parameters between the two groups （P〉0.05）. There was significant difference in the high encroachment group in radiological parameters before and after treatment （P〈0.001）. Conclusions：The posterior indirect decompression is a useful technique for patients with high or low ratio of spinal canal en-croachment after thoracolumbar burst fractures with an intact posterior longitudinal ligament. The integrity of posterior longi-tudinal ligament can be one of the most important indications of posterior decompression with distraction and ligamentotaxis.