克氏针钻头法在胸椎椎弓根置钉技术中的应用

目的评价克氏针钻头法在胸椎椎弓根置钉技术中临床运用的准确性及安全性。方法选择横突上嵴与上关节突基底中线的交点为进针点,2.5mm克氏针钻头缓慢旋转进入钉道直至深度为30mm。椎弓根探子确认钉道5个壁后,直径3.5mm丝攻进行攻丝,再次探查骨道后,根据术前CT测量拧入相应规格的螺钉。25例患者共210枚螺钉纳入临床研究,螺钉位置根据术后CT扫描并按照Heary进行分级,评价其准确性及安全性。结果采用克氏针钻头法置入胸椎椎弓根螺钉210枚,术中及术后未出现神经、血管及内脏损伤等并发症。术后CT扫描有18(8.57%)枚螺钉穿透骨皮质,4枚螺钉穿透椎弓根内侧壁<2mm。按照Heary分级,其置钉准确性达98.09%(206/210)。结论克氏针钻头法在临床运用中能准确而安全地置入胸椎椎弓根螺钉,并能缩短手术时间、减少医患人员的放射线危害。

A clinical application of novel K-wire drill technique for thoracic pedicle screw placement

Objective To evaluate the accuracy and safety of thoracic pedicle screw placement using a novel K-wire drill technique in clinical.Methods The junction of superior crista transverse process and midpoint of the base of the superior articular process was used as pedicle entry point.The 2.5 mm Kirschner wire drills were used to drill holes along with the pedicle until the depth of 30 mm.With the sounder confirming five intraosseous borders,the pedicle tract was undertapped with a tap of 3.5 mm in diameter.After second palpating the pedicle tract,suitable screws were placed slowly down the pedicle according CT scan before operation.Thoracic fusion surgery was performed in 25 patients for a total of 210 pedicle screws.On the basis of Heary scales,the accuracy of pedicle screw placement was evaluated using postoperative thin-section CT scanning.Results A total of 210 thoracic pedicle screws was placed by K-wire drill technique.There was no neurovascular and visceral injury.Eighteen screws violated the cortical wall on CT scan,and only 4 screws penetrated the medial cortical wall beyond 2 mm.The placement accuracy rate was 98.09% according Heary scales.Conclusion The K-wire drill technique is useful for accurate and safe placement of thoracic pedicle screws with the advantages of saving operation time and avoiding radiation exposure of the patient and surgeon.