VARIATIONS IN FORAMEN TRANSVERSARIUM

There are seven cervical vertebrae forming the skeletal framework of the back of neck. They are easily distinguishable from the other group of vertebrae by the presence of foramen in the transverse process namely foramen transversarium, which forms the characteristic feature of cervical vertebrae. The foramen transmits the second part of vertebral artery with the accompanying vein and the sympathetic plexus. The right and left vertebral arteries fuse at the level of Pons forming the Basilar artery which forms the main source of blood supply of the hindbrain. Therefore, any variation in the foramen transversarium has important clinical implications due to possible effects on the vertebral artery thereby causing hindbrain symptoms. In this study, 257 adult human cervical vertebrae were studied. The shape of foramina transversaria, symmetry of foramina on both sides and presence of accessory foramina were studied. It was found that the foramen was round in shape in 87.2 percentage, elliptical in 9.7 percentage and irregular in 3.11 percentage of the total vertebrae. Incidence of accessory foramen transversarium was found to be 8.56 percentage. Asymmetrical foramen was noted in 3.89 percentage of the total 257 cervical vertebrae studied.