青少年特发性脊柱侧弯胸椎椎弓根螺钉置入角度研究

摘要

Objective To analyze the entry angle for thoracic pedicle screw in the treatment of adolescent idiopathic scoliosis ( AIS) with three-dimensional reconstructed CT and to serve as useful references for safe and precise pedicle screw placement.Methods The three-dimensional reconstructed CT of T1 to T12 from 30 AIS patients with right-sided major thoracic curve were measured.The parameters included pedicle screw transverse angle , pedicle transverse angle , axial rotation angle of vertebra, pedicle chord length and pedicle width.Results On the right side, the pedicle screw transverse angle decreased gradually from T1 to T9 , then increased toward T12.On the left side, it decreased gradually from T1 to T4 , then increased to T9 and finally decreased to T12.On the right side , the pedicle transverse angle decreased gradually from T1 to T4 , then remained relative constant around 10° from T4 to T12.On the left side, it decreased gradually from T1 to T7 , then remained relative constant around 5° from T7 to T12.The mean axial rotation angle of vertebra decreased gradually from T1 to T3 , then increased to T9 , finally decreased to T12.The pedicle screw transverse angle significantly correlated to the axial rotation angle of vertehra ( P ＜ 0.05 ) and the pedicle transverse angle remained relative constant in the same thoracic level.The mean pedicle chord length of the whole thoracic spine was ( 37.0±5.1) mm.The mean pedicle width was (5.6 ±1.6) mm.Conclusion Knowledge about pedicle screw transverse angle, pedicle transverse angle, axial rotation angle of vertebra , pedicle chord length, pedicle width and the difference hetween the left and the right sides can serve as useful references for surgeons during pedicle screw placement.%目的 通过三维重建CT研究青少年特发性脊柱侧弯(AIS)胸椎椎弓根螺钉置入角度,指导在AIS手术治疗中安全、准确置入椎弓根螺钉.方法 对30例含有主胸弯的AIS患者T1-T12三维重建CT进行测量.测量的参数包括椎弓根螺钉横向角、椎弓根横向角、椎体轴面旋转角、椎弓根螺钉长度和椎弓根宽度.结果 右侧椎弓根螺钉横向角从T1逐渐减少到T9,然后上升到T12;左侧椎弓根螺钉横向角从T1逐渐减少到T4,然后增加到T9,最后减少到T12.右侧椎弓根横向角从T1逐渐减少到T4,从T4到T12相对稳定于10°左右;左侧椎弓根横向角从T1逐渐减少到T7,从T7到T12相对稳定于5°左右.椎体轴面旋转角从T1逐渐减少到T<,3>,然后逐渐上升到T9,最后减少到T12.椎弓根螺钉横向角和椎体轴面旋转角相关(P<0.05),在同一胸椎节段,椎弓根螺钉横向角和椎体轴面旋转角之间的椎弓根横向角相对恒定.椎弓根螺钉长度为(37.0±5.1)mm,椎弓根宽度为(5.6±1.6)mm.结论 掌握椎弓根螺钉横向角、椎弓根横向角、椎体轴面旋转角、椎弓根螺钉长度和椎弓根宽度的特点及其在凹侧和凸侧的差异对安全、准确置入椎弓根螺钉有重要参考价值.