下颈椎前路椎弓根螺钉植入的相关解剖学及影像学研究

目的通过测量成人下颈椎椎弓根的解剖学及CT图像相关参数,为临床应用下颈椎前路椎弓根螺钉内固定（ATPS）提供相关数据。方法成人干燥下颈椎标本24具及随机在CT室保存的34例成人患者的颈椎CT三维重建图像,测量C3-C7椎体的椎弓根宽（OPW）、椎弓根高（OPH）、椎弓根的中轴全长（PAL）、椎弓根外倾角（sPA）、椎弓根头倾角（tPA）、椎弓根投影中距（DtIP）、椎弓根投影上距（DsIP）,进行统计学分析,制定ATPS置钉参数。结果解剖学测量值与影像学测量值比较无统计学差异（P均〉0.05）。本研究提示：C3、C4进针点位于椎体正中矢状面受术椎弓根的对侧2-3 mm,距椎体上终板平面1-4 mm;C5进针点位于椎体正中矢状面受术椎弓根的同侧或对侧1-2 mm,距椎体上终板平面4-5 mm;C6、C7进针点位于椎体正中矢状面受术椎弓根的同侧3-5 mm,距椎体上终板平面5-8 mm。椎弓根中轴外倾角平均分别为C348°,C448°,C540°,C634°,C731°。椎弓根中轴头倾角平均分别为C384°,C489°,C5107°,C6114°,C7100°。置钉长度选择28、30、32、34 mm,螺钉的直径可选择3.0、3.5、4.0 mm。结论通过对下颈椎标本及成人下颈椎CT三维重建测量,并总结出进钉参数,证明下颈椎ATPS技术的可行性。

Anatomic and imaging related parameters measurement of anterior pedicle screw insertion in lower cervical spine

Objective To measure the related anatomic and CT imaging parameters of the pedicle of vertebral arch of lower cervical spine in adults in order to provide related data for clinical application of anterior transpedicular screw fixation （ATPS） in the lower cervical spine. Methods Selecting 24 dry cervical spine samples of adults and randomly selecting CT 3D reconstruction pictures of 34 adult patients conserved in CT database, the measured parameters in C3 - C7 vertebrae were as follows ： outer pedicle width （OPW） of vertebral body, outer pedicle height（ OPH）of vertebral body, pedicle axis length（ PAL）, sagittal pedicle angle（ sPA）, transverse pedicle angle（tPA）, distance of transverse intersection point （DtIP）, distance of sagittal intersection point （DsIP）. The statistical analysis was made, and then the parameters of implanted screws for ATPS were established. Results There were no statistic differences between anatomic and CT measurement for related parameters （ all P 〉 0.05 ）. The insertion points for C3 and C4 was 2 -3 mm opposite from operated pedicle in centrum median plane and 1 -4 mm from upper end-plate of centrum plane. The insertion point for C5 was 1 - 2 mm beside operated pedicle in centrum median plane and 4 -5 mm from upper end-plate of centrum plane. The insertion points for C6 and C7 were at the same side with operated pedicle, 3 - 5 mm beside centrum median plane and 5 - 8 mm from upper end-plate of centrum plane. The sPA of pedicle central axis at an average were 48°for C3 , 48°for C4, 40°for C5, 34°for C6, 31° for C7, respectively. The tPA at an average were 84°for C3, 89°for C4, 107°for C5, ll4°for C6, 100°for C7, respectively. For ATPS, the inserted screw lengths of 28 mm, 30 mm, 32 mm or 34 mm might be selected, and the screw diameters of 3.0 mm, 3.5 mm or 4. 0 mm might be selected. Conclusions By measuring the related parameters of the lower cervical samples and the CT 3 D reconstruction pictures of the lower cervical in adults, the feasibi