Morphometry of foramen transversarium of sub axial vertebrae and its variations: An osteological assessment

Abstract

Background: The occurrence of vertebrobasilar insufficiency caused by rotation of the head has been reported due to thickened fibroligamentous structures, osteophyte formation, duplication of foramen transversarium, and congenital absence of the foramen transversarium. The size and variations of the foramen transversarium plays an important role in vertebrobasillar insufficiency. Aim: The present study was carried out on the anatomical variations of foramen transversarium of subaxialvertebrae. Materials and Methods: The present study was the conducted in  Department of Anatomy, Nalanda Medical College and Hospital, Patna Bihar, India for 1 year. Total 120 dry sub axial cervical vertebrae (C3-C7) consisting of 240 foramen transversaria were collected for study. Among 120 vertebrae 75 belongs to typical type; 45 belongs to seventh cervical vertebrae.Results: Foramen transversarium of both sides of 120 sub axial vertebrae were studied. The anteroposterior length, transverse length and depth of foramen transversarium of both sides have been measured. The average antero-posterior length of foramen transversarium of typical cervical vertebrae and seventh cervical vertebrae were 5.52 mm ± 0.14 mm and 5.71 mm ± 0.91 mm respectively. The average transverse length of foramen transversarium of typical cervical vertebrae and seventh cervical vertebrae were 6.69mm±0.24 mm and 6.98mm±0.11mm respectively. The depth of foramen transversarium of typical cervical vertebrae and 7th cervical vertebrae were 3.41 mm ±0.12 mm and 2.90 mm ± 0.61 mm respectively. Conclusion: Anatomical knowledge on the dimensions of foramen transversarium of subaxial vertebrae and its variations will be useful for various spinal surgeries like spinal fixation procedures, decompression procedures.

Keywords: Double foramen transversarium, Bubble shaped foramen transversarium, sub axial cervical vertebrae