Variation in Cervical Pedicle Morphology: Important Considerations for Posterior Cervical Procedures

Area of Science:

• Neurosurgery
• Anatomy
• Radiology

Background:

• Safe posterior cervical spine surgery demands a thorough understanding of surgical anatomy and variations.
• The attachment site of the cervical pedicle to the vertebral body (VB) is critical for locating exiting nerve roots and requires preoperative assessment.
• The relative attachment site of the cervical pedicle has not been previously detailed.

Purpose of the Study:

• To characterize the pedicle attachment site to the vertebral body in the subaxial cervical spine.
• To quantify the prevalence and pattern of cervical pedicle attachment variations.

Main Methods:

• Review of cervical spine computed tomography (CT) scans from 2021.
• Creation of multiplanar reconstructions and cross-registration of images.
• Measurement of pedicle attachment relative to VB height using a novel calculation system.

Main Results:

• Analysis of 600 pedicles (C3-T1) from 50 CT scans.
• 78% of pedicles attached to the cranial third of the VB, 22% to the middle third; none attached to the caudal third.
• The highest prevalence of anatomical variation was observed at C3 (36%), decreasing linearly towards T1.

Conclusions:

• Cervical pedicles predominantly attach to the superior aspect of the VB, but considerable variation exists.
• Anatomical variation in pedicle attachment is most frequent at C3 and diminishes caudally in the subaxial spine.
• This study provides the first report on this specific morphological phenomenon in the cervical spine.