Morphological Study of Accessory Transverse Foramina in the Cervical Vertebrae

Aim: To study the incidence of accessory transverse foramina in the cervical vertebrae and analyze them morphologically. Material and Method: The study included 675 human cervical vertebrae which were procured from the bone collections of the Department of Anatomy. The transverse foramina were observed macroscopically on both sides of all the vertebrae; the accessory foramina were noted. Results: Out of 675 Cervical vertebrae, only 94 (13.94%) showed accessory transverse foramina. Among them 93 (13.77%) had double foramina and only 1 (0.15%) vertebra (C1) showed three foramina on left side. Out of 94 vertebrae, 46 (6.81%) had double foramen on both sides and 48 (7.11%) had double foramen on one side (28 (4.15%) on the right side and 20 (2.96%) on the left side). No vertebrae showed the absence of transverse foramina. Conclusion: The present study observed the accessory transverse foramina in 13.94% of cases. The unilateral presence was more common than the bilateral. Accessory transverse foramina were more common in vertebrae prominens (C7). The surgical anatomy of these variations is important since the course of the vertebral artery may be distorted in such situations and also for radiologists for interpreting the computed tomogram and magnetic resonance image scans