Lumbosacral transitional vertebrae are associated with lumbar degeneration:retrospective evaluation of 3855 consecutive abdominal CT scans

Abstract Objectives: To assess the prevalence of lumbosacral transitional vertebra (LSTV) and associated spinal degenerative changes on abdominal CT scans in Caucasian population. Material and methods: A total of 3855 abdominal CT scans of the year 2017 from a single hospital were retrospectively assessed for LSTV, disc degeneration (DD), and facet joint degeneration (FD). An age- and sex-matched 150-subject control group without LSTV was picked at random. Multivariable logistic regression was used for the analysis. Results: LSTV was found in 1101 (29%) scans: Castellvi type I in 68%, type II in 16%, type III in 13%, and type IV in 3% of scans. Age- and sex-adjusted prevalence of DD was significantly higher in Castellvi type II and III groups at multiple lumbar levels, and in IV group at L4/5 than in control group (p < 0.001–0.034). At L5/S1, the prevalence of DD was significantly higher in the control group than in type II, III, or IV groups (p < 0.001–0.017). After combining Castellvi types II, III, and IV into one group, significant differences were found at all lumbar levels except L2/3 (p < 0.001–0.016). Prevalence of FD was significantly higher at L4/5 in Castellvi groups I, II, and III than in the control group (p < 0.001–0.002). When Castellvi types II, III, and IV were combined into one group, significant differences were found at lumbar levels L2/3, L3/4, and L4/5 (p < 0.001–0.021). Conclusion: Lumbosacral vertebrae of Castellvi types II, III, and IV are associated with greater lumbar degeneration, warranting meticulous evaluation of spinal anatomy, even on CT