Abstract:

Objective　To measure the angle between the pedicle axis of lumbar vertebrae and the lateral border of vertebral plate and discuss its' clinical significance.　Methods　100 adult volunteers and 15 human lumbar spine specimens were chose to measure the angle between the pedicle axis of lumbar vertebrae and the lateral border of vertebral plate by the computer and the protractor, and then the collected data were compared and analyzed.　Results　 The angles obtained from X-ray images of volunteers were respectively, from L1 to L5, 90.7°±3.0°, 92.8°±3.0°, 94.6°±2.3°, 96.6°±2.6°, and 100.5°±3.2°. Significant differences appeared among different groups (P<0.05), but no gender difference appeared (P>0.05). The angles obtained from lumbar spine specimens were respectively 89.8°±3.3°, 91.9°±2.7°, 93.8°±2.4°, 95.1°±2.4°, and 99.2°±3.6°. As the results of X-ray data, there were significant differences among different groups(P<0.05), and no gender difference. Compared the data from X-ray images and specimens, there was no significant difference in L1, L2 and L3 (P>0.05), despite of the significant differences among L4 and L5 (P<0.05).　Conclusions　The insertion accuracy may be improved if the angle between the pedicle axis of lumbar vertebrae and the lateral border of vertebral plate can be used as the reference for the insertion of the pedicle screw.

Key words: Pedicle axis, Lateral border of vertebral plate, Angle, Lateral lumbar computed radiology, pedicle screw