Anatomical Study On The Height Of The Transverse Process Root Of C3-C7 And Its Clinical Application In Cervical Pedicle Screw Placement

Objective: Through measuring the anatomical height of the C3-C7 transverse process root H, calculating the number of H/2, to find whether there is a mean or other regularity in each cervical vertebra. If so, we just need probe the superior margin of the transverse process root during operation, then move down H/2 as the the horizontal line of the transverse process root, and the procedure will provide the theoretical basis for placement of C3-C7 pedicle screws.Methods: A total of 40 cervical vertebra specimens(excluding severe hyperplasia, bone fracture, deformities, or pathological damage) were prepared by the Department of Anatomy of the School of Basic Medical Sciences of Jilin University, regardless of their gender, age, height, weight and so on. The 200 segments from C3 to C7 vertebrae were obtained. After observing the anatomical character of C3-C7 transverse process, we measured the height of the C3-C7 transverse process root under direct vision. Analyzed the data with SPSS software.Results:(1) In C3~C7 segment, there is a increasing trend in the height of the C3-C7 transverse process root.(2) In the same segment, there is no statistical significance between the bilateral height of the C3-C7 transverse process root(P>0.05). So we combined the bilateral data, concluded that the half of the height of C3-C7 transverse process root(H/2) were 2.60±0.05 mm,2.82±0.08 mm,3.35±0.17 mm,4.00±0.12 mm,5.40±0.15 mm.(3) Additionally, we moved down H/2 distance from the superior margin of the transverse process root as the midline of the transverse process root, the intersection of this midline with the vertical line through the mediolateral third of the superior articular process is accurate on the projection of the axis of the pedicle on the dorsal lateral mass, which indicates that this intersection can be entry point of cervical pedicle screw safely.Conclusion: After the anatomical study about the C3-C7 transverse process, we observed a increasing trend in the height of the C3-C7 transverse process root and obtained a mean height(H/2) of each segment. It will provide a reliable theoretical basis and simplify the way of placement of C3-C7 pedicle screws.