It has been previously suggested in the literature that with aging, degenerative changes as well as disc herniation start at the lower lumbar segments, with higher disc involvement observed in an ascending fashion in older age groups. We conducted a study to investigate this correlation between age and level of disc herniation, and to associate it with the magnitude of the Lumbar Lordotic Angle (LLA), as measured by Cobb’s method. We followed retrospectively lumbosacral spine MRI’s of 1419 patients with symptomatic disc herniation. Pearson’s correlation was used in order to investigate the relationship between LLA, age, and level of disc herniation. Student’s -test was applied to assess gender differences. Young patients were found to have higher LLA ( , ) and lower levels of disc herniation ( , ), whereas older patients had higher level herniation in lower LLA group (mean LLA？28.6° and 25.4°) and lower level herniation in high LLA group (mean LLA？33.2°). We concluded that Lumbar lordotic Cobb’s angle and age can be predictors of the level of lumbar disc herniation. This did not differ among men and women ( , ). 1. Introduction The mechanical properties of the intervertebral discs, as well as the interplay between the vertebral spine curvature and the ligaments and musculature that maintain it, not only impart a resilience that is important in protecting the vertebral column against compressive forces encountered in various postures [1], but largely determine the changes induced by aging, which are subsequently associated with degeneration [2], tropism [3, 4], disc herniation [5], and lordosis [6]. These variations are level [7] as well as gender specific [8]. Published morphometric studies suggest that lumbar disc herniation is more cranially localized with age [5], and this finding is as well a mirror spread of degenerative changes [9] which start earlier at the lower lumbar levels [10]. The vertebral spine presents regional curves on sagittal plane, designed to absorb impact, reduce its longitudinal stiffness, and intensify muscular function; nevertheless, it has been noted that some cases of low back pain and sciatica are attributable to abnormal alterations of the curve [11]. Lumbar lordosis is defined as the curvature assumed by the intact lumbar spine to compensate for the inclination of the sacrum, restore an upward spinal orientation, and consequently avoid a forward inclination. Its measure, as proven by multiple investigators, is influenced by various parameters, including age, gender, pelvic bend, and thoracic curvature, among others [7, 8].
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