RT Journal Article SR Electronic T1 Decade-Wise Computed Tomography–Based Morphometric Measurements of a Single Lumbar Spinal Motion Segment L4-5 JF International Journal of Spine Surgery JO Int J Spine Surg FD International Society for the Advancement of Spine Surgery SP 795 OP 803 DO 10.14444/7113 VO 14 IS 5 A1 ARVIND G. KULKARNI A1 SAMEER RUPAREL A1 SUNILA JAGGI A1 NIHKIL MURKEY YR 2020 UL http://ijssurgery.com//content/14/5/795.abstract AB Background: A spinal motion segment comprises facet joints and intervertebral disc. A complex interplay of biomechanical factors occurs between them with degeneration giving rise to numerous pathological conditions. We conducted a study to find a correlation between facet joint orientation and intervertebral discs with age.Methods: A cross-sectional study of 203 consecutive subjects undergoing a computed tomography scan of abdomen and pelvis were included. Subjects were divided into 5 groups based on age (group I: 18–30 years; group II: 31–40 years; group III: 41–50 years; group IV: 51–60 years; group V: 61–70 years). Using 3-dimensional reconstruction images, orientation of lumbar facet joints at the L4-5 level was measured. Similarly, adjacent disc heights at L3-4 and L4-5 were measured and their ratio was documented.Results: The study included 106 males and 97 females. A positive correlation was noted between age and sagittal facet orientation until age 60 years. However, after age 60 years, a negative correlation with age was seen, which was statistically significant. Similarly, the disc height ratios show a progressive decline in their values with age. However, this decline was statistically significant only after age 60 years.Conclusion: The gradual change of facet joint orientation from sagittal to coronal as the age crosses from 30 to 60, to beyond 60, with a simultaneous and parallel diminishing in the disc height probably is one of the attributes of the phenomenon of autostabilization of a motion segment.