ABSTRACT
Objective To develop an anatomically based method of accurate pedicle screw insertion for cervical spine fixation. Methods Forty adult cervical spine were mounted onto a specially designed jig. Parameters including height, width, length, and axis angulation of pedicles,depth of lateral fovea, height of superior posterior border of arcus vertebrae and angles of posterior articular prominance as well were mea sured with vernier calibre or goniometer either directly or radiographically. Results Lateral fovea did exist in all C2-C7 vertebrea. The pedicles of the cervical spine were wide and long enough to accept 28 mm long 3.5 mm screws. The abduction angle of the screw was 20? at the C1 level, 25? superiorly and 44? inferiorly at the C2 level, 45? to 47? from level C3 to C5, and 40? from level C6 to C7. The angle of posterior plane of articular mass was minus 2.30? at C3,it was 2.32? to 2.42? from level C4 to C6, and it was 15.22? at C7. The stability of cervical spine fixation and neurological improvement were satisfactory. Conclusion Transpedic ular screw fixation for the cervical spine is practicable. Anatomical symbol of the superior posterior border of the arcus vertebrae and the posterior plane of articular mass and the lateral fovea is easy to be exposed and identified in the operation. Transpedicular screw can be precisely inserted easily and safely for the cervical spine fixation with limited exposure and without using fluoroscopic guidance.