RESUMO
The determination of the lumbosacral angle is one parameter that is of importance in evaluating the possible etiology of low back pain syndromes, therefore the purpose of this study is to define the normal range of intervertebral disc angulation at L5 and S1 and, to evaluate the tube angle used in practice to demonstrate the disk space in the anteroposterior projection. Two hundred and twenty lateral scout CT scans were examined in patients who were 110 male and 110 female, with an average age ranged between 30 to 90 years old. The intervertebral angles for L5 and S1 were measured using CT soft ware. A set of coefficient was used in an arrangement to formulate the necessary x-ray angle for males and female of a known age and intervertebral L/S angle. The results of this study found that the range of normal inter vertebral lumbosacral angulations is approximately 60 [degree sign] and 53 [degree sign] in male and female in respectively, and at antero-posterior projection, 30[degree sign] cranial tube angulations for males and 37[degree sign] cranial angulations for females should be used for inter vertebral lumbosacral visualization