Atlantoaxial digital 3D shape measurement of school-age children

English Keywords:Atlantoaxial  Digital measurement  3D shape  School-age children

English Abstract:

  【Abstract】 Objectives: To investigate the CT three-dimensional imaging of morphology of atlantoaxial in school-age children(7-12 years old), and to provide a theoretical basis for early diagnosis and prevention of atlantoaxial disease in children of school age. Methods: The cervical CT scan data of school-age children images in Chifeng Hospital and the Affiliated Hospital of Inner Mongolia Medical University from 2013 to 2014 were collected, patients with atlantoaxial fractures and deformity, tuberculosis and other diseases were excluded in this study. The original DICOM data were transferred to 3D reconstruction with Mimics 16.0, the software of 3D measurement tools was used to measure the atlantoaxial lateral mass and pedicle related indexes in the reconstruction of three-dimensional model. In atlas, the parameters included lateral mass diameter(LMD), angle lateral mass block(d), lateral mass before and after(LMB), angle lateral mass on the side(e), atlas pedicle width(AW), atlas pedicle length(AL), atlas pedicle outer angle(b), atlas pedicle height(AH) and atlas pedicle end angle(c). In axis, the parameters included axis pedicle length(APL), axis pedicle width(APW), pivot angle outside vertebral pedicle(f), axis pedicle height(APH) and axis pedicle end angle(g). The subjects were divided into three groups according to their age, group A(7-8 years), group B(9-10 years) and group C(11-12 years old). Results: The LMD increased with age increasing, the LMD of group A was 13.91±1.95mm on the left, 14.11±1.95mm on the right; the LMD of group B was 14.31±2.24mm on the left, 14.36±2.39mm on the right; the LMD of group C was 17.18±2.32mm on the left, 17.10±2.41mm on the right; There were significant differences in left LMD between group C and group A or B(P＜0.05). There were significant differences in LMD between the left and right side of same group(P＜0.05). Other parameters also showed a trend of increasing with age, there was significant difference between group C and group A of same side(P＜0.05), except angle f; there was significant difference between group C and group B of same side(P＜0.05) in AH, APW and APH; there was significant difference between group B and group A of same side(P＜0.05) in AL, AW, APL, APH and angle g; there was significant difference between the left side and right side of same group(P＜0.05) in LMB and angle d. Conclusions: Though the morphology of atlantoaxial pedicle and lateral mass in school-age children is complex and not fully developed, the three-dimensional bony structure development pattern provides reference for clinical and further study of adjacent structures.