Chronology of disc degeneration and facet joint arthritis in lumbar spine is variable- A CT based cross-sectional study

Background: The notion that disc degeneration (DD) always precedes facet joint arthritis (FJA) has held sway for many decades. However, it is not always the case. We hypothesized that DD is not always the first offender studied the prevalence of isolated DD and isolated FJA in the lumbar spine.Methods: Inter-vertebral discs and bilateral facet joints of lumbar spines of 135 participants were graded. The participants were divided into one of the four categories. 'No degeneration,' 'Isolated disc degen-eration without facet joint arthritis,' 'Combined disc degeneration and facet joint arthritis,' and 'Isolated facet joint arthritis without disc degeneration.' Multivariate logistic regression analysis was done to evaluate the predictive factors for spinal degeneration using FJA as a dependent variable while age, sex, BMI, smoking history, and DD as predictor variables.Results: The majority of participants had isolated FJA 64 (47.4%). Combined DD and FJA were noted in 32 (23.7%), isolated DD in 8 (5.9%), while 31(23%) had no degeneration. Only age was found to be signifi-cantly contributing to the prediction model in multivariate analysis.Conclusion: Our study shows that spinal degeneration may begin either in the disc or in the facet joints depending upon the aetiological factors. It is a vicious circle that may be entered at any point, FJA or DD.(c) 2021 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.