椎弓根螺钉固定的X线定位诊断

RADIOGRAPHIC DIAGNOSIS OF THE LOCATION OF PEDICLE SCREW FIXATION

本文以干燥成年男性腰椎为标本，利用椎弓根螺钉、ｓｔｅｆｆｅｅ钢板及ｘ线机通过多角度系统拍片对比研究，提出了椎弓根螺钉固定中几个常见的错误包括偏上、偏下、偏内、偏外、过长等，并且获得了高阳性率的特殊拍片法。认为螺钉或椎弓根的轴位片，左右３０度斜位及头倾１０度片，能够清晰地显示椎弓根螺钉的位置错误，在椎弓根螺钉的定位诊断中优于常规的正侧位拍片法。

Radiography was employed in locating the Pedicle screw during or after orthopedic surgeries. However,the projections of the pedicle and the screw could not be shown clearly on the same axis picture,As a result,the left and right positions are overlapping,producing a very Low Positive rate in detecting the position of the pedticle screw in the picture. Comparing with various radiographic techniques,the authors fouad that the incorrect position of the pedicle screw could be shown clearly on the axis radiograph taken at a 30-degee tilting Position and/or10-degree inclination of the head.