Abstract:

BACKGROUND: Because of small perimeter, different heights, complex anatomic structures of pedicle of cervical vertebra, the pedicular implantation may damage spinal cord, vertebral artery or nerve root. Correct understanding of pedicle and surrounding anatomic structures facilitate improvement of safety of transpedicular screw fixation.
OBJECTIVE: To evaluate clinical significances of CT measurement of cervical vertebra pedicle in transpedicular screw fixation.
METHODS: The cervical segments of 81 health adult vertebrae were measured by CT. The measured indexes included 13 items: pedicle height, pedicle width, lateral, internal, inferior and superior cortical thicknesses, spongy bone height and width, total pedicular length, pedicular length1, pedicular length2, pedicular transect angle and pedicular sagittal angle.
RESULTS AND CONCLUSION: The pedicle width was smaller than corresponding height, and pedicle size was the smallest at C₃ and C₄ levels; the spongy bone diameter was small and cortical bone was high. The lateral cortical thickness was the thinnest among the internal, inferior and superior cortical thicknesses. The total pedicular length, the pedicular length1 and the pedicular length2 remained unchanged in C₃ to C₇, but there were some differences with the pedicular transect angel and the pedicular sagittal angle. CT can display internal morphology of lower cervical pedicle clearly and provide radiology data for transpedicular screw fixation.