A cone beam computed tomographic analysis of cervical vertebral nonsegmentation

Using cone beam computed tomography (CBCT), this study aimed to investigate the radiologic features of cervical vertebral nonsegmentation (CVN) in patients with no known syndromes or pathoses.

In this retrospective study, we examined CBCT scans of patients with CVN for the following parameters: type of nonsegmentation (partial or complete); laterality of partial nonsegmentation; level of vertebrae affected in nonsegmentation; anatomic parts of the vertebrae involved; and the presence or absence of degenerative joint disease (DJD).

From the structured reports of 13,458 CBCT scans, we found 110 CBCT scans (0.82%) with CVN. Of this total, 77.3% were partial and 22.7% were complete. Most were located at the level of the C2 and C3 vertebrae. The transverse process alone and the transverse process and body were most frequently involved in partial CVN, whereas most complete types occurred in the transverse process and body. Degenerative joint disease was present in 45.9% of partial CVN (clearly distinguishable from nonsegmentation in 36.5%) and 20% of complete CVN, with all cases clearly distinguishable.

Cervical vertebral nonsegmentation has a low prevalence. It is mostly partial, occurs most commonly in C2-C3, and usually involves the transverse process and body. Identification of CVN on CBCT images is important because this condition can lead to DJD in older age and may increase the risk for muscle weakness, head and neck pain, limited movement, and neurologic complications.