VARIATIONS OF FORAMEN TRANSVERSARIUM IN ATLAS VERTEBRAE : A MORPHOLOGICAL STUDY WITH ITS CLINICAL SIGNIFICANCE

Abstract

Abstract Introduction: The second part of the vertebral artery along with vertebral venous plexus and sympathetic plexus traverses through vicinity of foramen transversarium of atlas. Derangement of these structures in their course may be seen due to deformities, narrowing and presence of osteophytes in foramen transversarium. Methods: Two hundred foramen transversarium of 100 atlas vertebrae were grossly studied for their variations. Results: Out of hundred atlas vertebrae examined, we found that all the vertebrae had foramina transversaria. Absence of costal element was noticed in five atlas vertebrae. 2 of the vertebrae showed incomplete unilateral foramen transversarium, 3 vertebrae showed bilateral incomplete foramen, In 1 vertebra along with normal foramen transversarium, complete retroarticular foramen was observed on the left side and incomplete retroarticular foramen observed on the right side of the posterior arch.4 vertebrae showed incomplete retroarticular foramen. Conclusion: The increasing incidence of neck injuries and related syndromes necessitates the study of bony variations of the atlas vertebra and its transverse foramina. Due to the incomplete formation of the foramen transversarium the second part of vertebral artery is prone to be damaged easily during posterior cervical injuries and Surgeries. The bony bridges embracing the vertebral artery may be responsible for vertigo and cerebrovascular accidents hence the knowledge of such variations is important for Physicians, Otirhinolaryngologists, neurologists ,Orthopaedicians and Radiologists.