术前应用螺旋CT个体化测量在骶髂关节置钉中的意义

目的　探讨切开复位骶髂螺钉内固定术前应用螺旋CT个体化测量健侧螺钉钉道参数，指导术中置钉的可行性。 方法　⑴对10例冰冻正常成人骨盆标本进行螺旋CT扫描与多平面重组，在不同重组图像中依次测量左右侧S1螺钉的进针方向、进针点与髂后上、下棘的距离、钉道的长度与安全角度等参数；⑵将10例骨盆标本左右侧骶髂关节制成垂直不稳定贩折模型，然后左右侧骶髂关节分别根据对侧的CT测量结果进行个体化置钉验证。 结果　⑴进针方向与冠状面、水平面的夹角分别为（25.95±　1.39）°与（19.61±2.97）°，进针点与髂后上、下棘的距离分别为(37.17±2.90)mm与(38.23±1.69)mm，冠、轴状面上的安全角度分别为(19.87±1.61)°与(23.84±2.08) °；⑵左侧骶髂关节所置10枚螺钉均安全、准确地到达S1椎体预定位置；右侧骶髂关节所置螺钉除1枚偏离突出骨质外，其余9枚均安全到达S1椎体预定位置。 结论　切开复位骶髂螺钉内固定术前应用螺旋CT个体化测量健侧螺钉钉道参数，指导术中置钉的方法是可靠的。

The significance of individual measuring by preoperatively application of helical computed tomography in the placement of screw on the sacroiliac joint

Objective To explore the feasibility of individual measuring the parameters of the screwing trajectory of the screw on the uninjured side by application of helical computed tomography before open reduction and internal fixation using sacroiliac screw to guide the placement of screw on the injured side.Methods(1) Ten frozen pelvic specimens of normal Chinese adults were scanned and multiplanarly reconstructed by helical computed tomography in order to measure the entrance direction of the S1 screw,the distan...