椎弓根轴线导向器的研制和应用研究

Design and application of orientation apparatus of vertebral pedicle axes

目的:通过解剖学标本研究和临床应用评价椎弓根轴线导向器引导椎弓根螺钉置入的准确性和安全性。方法:①解剖标本研究:全长脊柱标本6具(研究范围T1-S1),术前行螺旋CT扫描,测定椎弓根轴线入点间距、椎弓根轴线角度及其延长线在椎体内的长度。根据测量数据,应用椎弓根轴线导向器引导直径2.5mm克氏针沿椎弓根轴线置入。术后拔出克氏针,复查脊柱标本CT,分别测量记录数据:各椎克氏针钉道及延长线与椎体长轴线在水平面的交角(记作KTSA);矢状面上与棘突轴线的交角(记作KPSA);各椎实际入钉点间距(KDSP)。采用SPSS10.0统计软件分析所采集数据。②临床应用:应用于26例患者,男16例,女10例;年龄21～71岁,平均49.5岁。在导向器引导下共置入椎弓根螺钉112枚。术后通过CT或MRI验证置钉的准确性。结果:①解剖研究:克氏针的钉道与椎弓根轴线所成水平面角和矢状面角相接近(P>0.05);实际入钉点与设计入钉点重合(P>0.05)。②临床应用:术后所有病例共112枚椎弓根螺钉经CT或MR图像复查,按置入位置判断标准,优107枚(95.5%),良3枚(2.7%),差2枚(1.8%)。结论:椎弓根轴线导向器可以准确地引导顺椎弓根轴线钻孔,从而提高椎弓根钉置入的准确性和安全性。

Objective：To evaluate the accuracy and safety of screw insertion with the guidance of orientation apparatus of vertebral pedicle axes through anatomic studies and clinical application. Methods： （1）Anatomic study： 6 spinal specimens （ranged from T1 to S1 ）in which the distance between two entry points of screws, the angles （TSA/PSA）of pedicle axis as well as the length of the pedicle axes were measured by spiral CT scan. Basing on the collected data,inserted the K-wires（2.5 mm of diameter）into vertebrae along the pedicle axes guided by the orientation apparatus. Pull out the K-wires after the operation. The specimens took another CT scans and the data including KTSA, KPSA, KDSP were collected. These data were analyzed with the SPSS 10.0. （2）Clinical application ： 112 screws were inserted into vertebral pedicle in 26 patients with the guidance of orientation opparatus. There patients included 16 male and 10 female, with the mean age of 49.5 years（ ranging from 21 to 71 ）. The accuracy of screw insertion was evaluation through CT scans or MRI. Results： （1）Anatomic study：the angles of the track of K-wire in horizontal plane and sagittal plane were close to those of vertebral pedicle axes （ P 〉 0. 05 ） ; the actual entry point of vertebral pedicle axis and scheduled entry point were superimposed （P 〉 0.05 ）. （2）Clinical application：compared with the standard insertion position, the outcome was excellent in 107 screws （ 95.5% ）, good in 3 （ 2. 7% ） , poor in 2 （ 1. 8% ）. Conclusion ：The orientation apparatus can exactly guide operator to drill along the vertebral pedicle axes, thus, it can increase the accuracy and safety of the pedicle screw insertion.