Morphometric study of cervical spinal canal and transverse foramen diameter using computed tomography: Sex difference...

Accurate and detailed spinal canal diameter transverse foraminal morphometry measurements are essential for understanding spinal column-related diseases and surgical planning, especially for transpedicular screw fixation. This is especially because lateral cervical radiographs do not provide accurate measurements. This retrospective study was conducted to measure the dimensions of the transverse foramen sagittal and transverse diameter (TFD), spinal canal diameter, the distance of the spinal canal from the transverse foramina at the C1 to C7 cervical level, and the anteroposterior and TFDs in the Turkish population. A total of 150 patients who underwent cervical spine computed tomographic imaging with a 1:1 gender ratio were enrolled in the study. The sagittal and TFDs of the spinal canal, the distance of the spinal canal from the transverse foramen, and anteroposterior and TFDs in both right and left sides for all cervical levels C1 to C7. Foramina transversal diameters were measured using imaging tools of the imaging software in the radiology unit. The mean age of the study group was 47.99 ± 18.65 (range, 18-80) years. The majority of the distances of the spinal canal from the transverse foramen and antero-posterior (AP) & transverse (T) diameters for cervical vertebrae were significantly higher in male patients (P < .05). However, between age groups, a few measurements were found significantly different. Some of the distances of the spinal canal from the transverse foramen were significantly higher on the right side whereas all AP & T diameters were significantly higher on the left side in both male and female patients (P < .05). Almost all measurements were significantly higher on the left side for younger patients (<65 years) whereas only AP & T diameters were significantly higher on the left side for older patients (>65 years) (P < .05). Computed tomographic imaging is better than conventional radiographs for the preoperative evaluation of the cervical spine and for a better understanding of cervical spine morphometry. Care must be taken during transpedicular screw fixation, especially in female subjects, more so at the C2, C4, and C6 levels due to decreased distance of the spinal canal from the transverse foramina.