椎弓根定向爆裂器在胸腰段椎体骨折后路固定术中的应用

A pedicle directional breaking device for posterior fixation of fracture of thoracolumbar vertebrae

目的 探讨椎弓根定向爆裂器在胸腰段椎体骨折后路固定术中的应用. 方法 对2009年5月至2012年10月收治的31例胸腰段椎体骨折患者资料进行回顾性分析,年龄19 ～56岁,平均42.9岁;男11例,女20例.骨折节段：单节段,T12 3例,L111例,L210例;双节段,T11、T124例,T12、L13例.骨折按照Denis分型：压缩型16例,爆裂型15例.神经功能按Frankel分级：A级2例,B级1例,C级3例,D级5例,E级20例.椎弓根横径：5 mm者15侧,4～5 mm者26侧,＜4 mm者7侧.所有患者行后路椎弓根钉棒系统复位固定时采用在现有的“开路器”的基础上自行改进的椎弓根定向爆裂器置钉. 结果 本组31例患者术后获12 ～ 28个月（平均16.8个月）随访.术后无脊髓损伤加重及感染等并发症发生.X线片观察见椎体高度及后凸畸形明显恢复.术后CT示椎管减压充分,螺钉均未进入椎管内,椎弓根爆裂者内壁完整,外壁胀裂状,螺钉大部分被椎弓根骨质包裹.伤椎愈合时间为3～6个月,随访期间未发现断钉、脱钉现象.本组患者术后1周内伤椎相对高度和cobb角与术前比较改善,差异均有统计学意义（P＜0.05）,内固定取物出后伤椎相对高度和伤椎cobb角与术后1周内比较差异均无统计学意义（P＞0.05）.伴神经损伤者,多获明显恢复. 结论 采用椎弓根定向爆裂器进行细小椎弓根的螺钉置入操作准确、简单易学,且安全有效,为椎弓根细小者行后路固定术提供一种新方法.

Objective To evaluate the application of a self-designed pedicle directional breaking device in posterior fixation of thoracolumbar vertebral fracture.Methods From May 2009 to October 2012,31 patients with thoracolumbar vertebral fracture were treated at our hospital.They were 11 men and 20 women,from 19 to 56 years of age （average,42.9 years）.The fractures involved T12 in 3 cases,L1 in 11 cases,L2 in 10 cases,both T11 and T12 in 4 cases,and both T12 and L1 in 3 cases.By Denis classification,16 cases were compression fractures and 15 burst fractures.By Frankel＇ s classification of neural function,2 cases were grade A,one grade B,3 grade C,5 grade D,and 20 grade E.The transversal diameter of the pedicle was 5 mm in 15 sides,from 4 to 5 mm in 26 sides and 〈 4 mm in 7 sides.A self-designed pedicle directional breaking device was used in the posterior fixation of thoracolumbar vertebral fracture for all the patients.Results The 31 patients were followed up for an average of 16.8 months （from 12 to 28 months）.No deterioration of spinal cord injury or infection happened after operation.X-ray films showed obvious restoration of vertebral height and kyphosis.Postoperative CT scans showed no penetration of the pedicle screws into fully decompressed spinal canals.The burst pedicles had a broken outer wall but an intact inner wall.The screws were mostly wrapped by pedicle bone.The injured vertebrae got healed after 3 to 6 months.No screw failure happened during follow-up.At one week postoperation,the average relative height and cobb angle of the injured vertebrae were significantly improved compared with preoperation （P 〈 0.05）.The average relative height and cobb angle of the injured vertebrae after removal of internal implants were not significantly different from those at one week postoperation （P 〉 0.05）.Most of the nerve injuries were obviously recovered.Conclusions Our self-designed pedicle directional breaking device is simple,safe and effective.It provides patients with narrow pedicles with a new instrument which facilitates posterior fixation of thoracolumbar vertebral fracture.