Morphometric studies on sexual dimorphism, variations and dimension of foramen transversarium in a KwaZulu-Natal population, South Africa.

Abstract

The foramen transversarium (FT) of the cervical vertebrae serves as an essential landmark in medical imaging procedure and surgery, owing to their anatomical structure in relation to the associated neurovascular bundles. The aim of this study was to analyse the morphometric parameters and variations of the FT with regards to sexual dimorphism, laterality and age within the KwaZulu-Natal (KZN) population, South Africa. One hundred and thirty (130) dried human typical cervical bones from KZN population of known sex and age (67 males and 63 females with age ranges from 12 to 89) without any degeneration or deformity were sourced from the bone collection at the Discipline of Clinical Anatomy, Nelson Mandela School of Medicine, University of KwaZulu-Natal (UKZN). The morphometric analyses were performed using Markus Bader (MB) Ruler, the digital screen ruler and subjected to RStudio statistical analysis. The results indicated that the morphometric parameters of the FT were greater in males compared to females (p< 0.05). The values of the right sides were higher than that on the left sides except, for the transverse diameter where higher values were observed on the left side of male specimens. Based on the shape of normal FT inspection, the type 1 was predominant (43.85%) shapes, followed by type 3 (23.08%) and least common were type 2 and type 7 (0.77%) on the left side. Type 1 had the higher value (46.16%) on the right side, followed by type 3 (20%) and, type 2 was the least in this study. The variation in number of FT in relation to sex revealed the presence of normal foramen (62.31%, male with 30.77% and female with 31.54%) and double foramen (36.92%, male with 20% and female with 16.92%). More so, it was also observed that, the frequency of bilateral double foramen was common in males (11.54%) compared to females (6.92%). The result of this study has demonstrated that risk of injury to neurovascular structures associated with FT may be common on the left side, in female and especially in age groups less than < 20 and ≥ 60 years of age. Keywords: Foramen Transversarium, Cervical vertebrae, Variations, Sexual Dimorphism, Morphometric.