正常儿童胸椎椎弓根数字化形态学研究

Digital morphological study of thoracic pedicle in children

目的通过对4~12岁正常儿童胸椎椎弓根的数字化形态学测量,探讨其形态特征及发育特点,为儿童胸椎椎弓根螺钉内固定术提供理论依据。方法收集60例正常儿童胸椎CT扫描数据,间隔3岁为1个年龄组,共分为3组,每组20例,将CT资料导入Mimics软件三维重建后测量椎弓根宽、椎弓根高、钉道长、e角和f角等相关参数。结果椎弓根宽、椎弓根高、钉道长总体随年龄增长呈递增趋势,10~12岁组与4~6岁组、7~9岁组组间差异均有统计学意义(P<0.05);椎弓根宽随椎序先减小再增大,椎弓根高、钉道长总体随椎序的增加呈明显递增趋势,e角、f角则在3组间差异无统计学意义(P>0.05),e角总体随椎序的增加呈递减趋势,而到T_(11)~T_(12)为负角,f角总体呈波浪状下降趋势。结论 4~12岁正常儿童胸椎椎弓根相关参数随年龄的增长存在着较大的差异,提示临床对这一群体行椎弓根螺钉内固定术时应尽可能体现"个体化置钉"原则,以提高儿童椎弓根螺钉内固定术的成功率。

Objective To investigate the morphological regularity of the thoracic pedicle screw in 4 to i 2 years old children by the digit- al technology, and to provide the theoreticl basis for thoracic pedicle screw fixation in children. Methods A total of 60 healthy children aged from 4 to 12 years old with computed tomography （CT） data of thoracic spine were divided into three groups by age, each group 20 eases. Then they were examined by MIMICS software and the parameters of pedicle width （ PW ） , pedicle height （ PH ）, the length of screw path （ SL）, e angle and f angle were measured. Results The pedicle width, pedicle height, the SL of the pedicle generally showed a rising trend with advancing age. There were significant differences in the PW, PH and LS between the three group （ P 〈 0.05 ）. The PW decreased and then increased. The PH and the KS increased with the vertebral order increased. There was no significant difference in e angle and f angle between the three groups（ P 〉 0.05 ）. E angle of the pedicle generally showed a decreasing trend with increasing vertebral order,and e angle of TN to Ti2 showed negative angle. The f angle showed a wavy descending trend. Conclusion There was significant difference in correlation parameters of thoracic pedicle with increasing age in healthy children, which indicates that the pedicle screw fixation for the kind of children should be performed based on ＇ the Principle of individualization to improve the success rate of surgery.