ABSTRACT
Background: Pedicle screw fixation for mid- and lower cervical spine reconstruction has a potential risk of injuryto surrounding structures. To achieve optimal surgical outcomes, it is therefore necessary that pertinentanatomical data, especially with regard to pedicles and vertebral bodies be considered prior to surgery.Methods: 63 patients were scanned using axial CT parallel to the upper endplate of the vertebral body (C3–C6)with a helical CT scanner. Foramen width (FW), Foramen height (FH), Pedicle width (PW), Foramen angle (FA),Pedicle transverse angle (PTA), Lateral mass angle (LMA) were measured. Mean value and standard deviation ofeach parameter were calculated.Results: Mean FW ranged from 5.8 to 6.1 mm with non-significant difference from C3 to C6.The mean FH rangedfrom 4.9 to 5.1 mm, with non-significant differences between each vertebra. The mean PW ranged from 5.3 to 5.8mm. There were significant differences between each vertebra, except for the PW between C3 and C4. The FAranged from 17.5 to 18.5. There were significant differences between each vertebra, except for the FA between C3and C6. The mean PTA ranged from 39.8 to 35.8. The mean LMA ranged from 0.9 to 3.1.There were significantdifferences between each vertebra, except for the LMA between C4 and C5. The FW and FH exhibited no correlationswith PW, PTA or LMA. FA was found to be positively correlated with both PTA and LMA. There was also a positivecorrelation between PTA and LMA.Conclusion: Anatomical features of the cervical spine using CT to select safer screw insertion techniques arehighly recommended. In cases in which insertion of pedicle screws is difficult, Lateral Mass Screw (LMS) can beinserted safely. Whereas when insertion of LMS is difficult, insertion of pedicle screws can be performed easily.