Vascular structures are in greater danger during lumbar surgery. The purpose of this study is to describe the morphology of the inferior vena cava (IVC) related to the lumbar vertebra and aortic bifurcation (AB) and assessing the role of demographic values in these relations to decrease the risk of complications in the surgical interventions. The study was performed on Multidetector Computed Tomography (MDCT) images of 100 male and 100 female cases with an age range from 50 to 84 years. The morphometric values of the IVC obtained from the coronal, sagittal and the axial reformatted images were measured and compared with the demographic values. The distance from the IVC to the 1st lumbar vertebra (L1) and 2nd lumbar vertebra (L2) were measured as (26.5 mm and 18.1 mm) in males and (21.1 mm and 14.2 mm) in females with a high level of significance between genders; the distance from the IVC to the iliocaval confluence (IC), 3rd lumbar vertebra (L3) and 4rd lumbar vertebra (L4) were measured as (6.5 mm, 10.5 mm and 6.9 mm) in males and (4.9 mm, 9.1 mm and 5.5 mm) in females with significance between genders. The level of the IC was detected 46 % of males, 39 % of females at the level of lower third of L4. The vertical distance between the IC and the AB was measured and negative correlation between genders based on age was detected. Demographic values are important to consider the relationship of the IVC, the lumbar vertebra and the AB. The IVC was located further from the lumbar vertebra in males compared to females. Age increase played role in the approaching of the AB and the IC to each other in both gender and the IC to the promontory level in males.