胸椎椎弓根螺钉置入中"漏斗技术"的准确性研究

目的 探讨"漏斗技术"在胸椎椎弓根螺钉置入中的准确性,并对该技术的实验和临床应用一致性进行比较.方法 回顾性分析2006年8月-2008年7月至少有1枚螺钉置于T1～T12的3具人类尸体标本和11例患者的资料.由一位缺乏胸椎弓根螺钉置钉经验的年轻脊柱外科医师采用"漏斗技术"完成全部螺钉的置入.根据术后薄层CT扫描评估置钉准确性及各种并发症.结果 平均随访时间23.1个月,未见医源性血管、神经或内脏损伤等并发症;置钉失败率在标本和患者分别为14%(10/72)和15%(8/55);标本和患者危险性穿破分别为2枚(3%)和1枚(2%);置钉准确性在标本和患者之间差异无统计学意义;11例患者中,6枚(11%)螺钉穿破椎弓根外侧壁,1枚(2%)螺钉穿破椎弓根内侧壁,1枚(2%)螺钉穿破椎弓根上壁,未见椎弓根下壁和前壁穿破;患者置钉准确性比较:T1～T4比T5～T8(P＞0.05)、T1～T4比T9～T12(P＞0.05)、T1～T8比T9～T12(P＞0.05).在所有患者中,仅1枚螺钉需要重置.年轻脊柱外科医师在第1、第2、第3具标本上发生置钉失败数分别为6枚、3枚和1枚.结论 "漏斗技术"是一种简单、安全、准确和经济的椎弓根螺钉置入方法.实验研究与临床应用一致,通过该技术使年轻医师迅速安全、准确置入胸椎弓根螺钉成为可能.

Accuracy of "funnel technique" in the thoracic pedicle screw instrumentation: experimental and clinical study

Objective To evaluate the accuracy of thoracic pedicle screw placement using the "funnel technique" and investigate its consistency in experimental study and clinical application.Methods The clinical data of three human cadavers and 11 patients with the installation of at least one thoracic pedicle screw at T1 -T12 from August 2006 to July 2008 were retrospectively analyzed. One junior spine surgeon lack of experience were responsible for placing these screws with the "funnel technique".The accuracy of screw placement and the complications related to the use of thoracic pedicle screws were analyzed by assessing postoperative CT scans. Results The mean follow-up time was 23.1 months,which showed no vascular or visceral complications, or iatrogenic neurological injury. The rate of unintended cortex perforations was 14% (10/72) in cadavers and 15% (8/55) in patients, respectively.The critical perforation occurred in two screws (3%) in cadavers and one screw (2%) in patients. There was no statistical difference between the percentage of cortex perforations in cadavers and patients. Of all the 11 patients, screw violation occurred laterally in six ( 11% ), medially in one ( 2% ) and superiorly in one (2%). No violations occurred inferiorly or anteriorly. For all patients, only one screw needed revision. The perforations made by the junior spine surgeon occurred in six screws in the first cadaver, three in the second cadaver and one in the third cadaver. Conclusions The "funnel technique" is a simple,safe, accurate and cost-effective technique for pedicle screw placement. The result of the experimental study is consistent with that of the clinical application. "funnel technique" is helpful for junior spine surgeons to master the technique of thoracic pedicle screw placement.