An Anatomical Study of The Lumbar Epidural Space in Egyptians using Computerized Axial Scans

Background: Racial differences have been proven to exist in different morphometric measurements. Therefore, each population should have its own measurements to provide a complete and accurate data base. The precise dimensions of the lumbar epidural space are critical for many spinal surgeries. However, the existed data-base is limited in accuracy as well as in the parameters recorded. Aim of the Work: This study was performed to provide a large and accurate data base of lumbar epidural spinal morphometric measurements in a segmental manner in normal Egyptian population and to clarify the influence of age and sex on these measurements. Subjects and Methods: Morphometric characteristics of the lumbar epidural space were studied in 160 Egyptians aged 27- 74 years using computerized axial scans. Results: The study revealed sex- and age-dependent differences in some of the measurements of the lumbar epidural space. The ligamenta flava thickness increased significantly with advancing age, while the length decreased significantly. The presence of fat in the antero-lateral recesses was more by age increase. On the other hand, the distance from the skin to the posterior epidural space and the distance from the posterior wall of the spinal canal to the dural sac decreased significantly with age. Moreover, the transverse and the anteroposterior diameters of the spinal canal, the facet joint space and the depth of the lateral recess decreased significantly with advancing age. Regarding gender, the distance from the skin to the posterior epidural space was significantly longer in females than in males. While length and thickness of ligamenta flava, the facet joint space and the depth of the lateral recess were significantly more in males. Conclusion: Computerized axial scan clearly may reveal the anatomy of the epidural space, and this work may be a useful guideline to the anatomy of the lumbar spine among Egyptians. Data obtained should be considered during evaluation of the state of the lumbar epidural space before and during spinal surgery and in the diagnosis of the pathological processes in the lumbar region