Increased vertebral body area, disc and facet joint degeneration throughout the lumbar spine in patients with lumbosacral transitional vertebrae.

ABSTRACT

OBJECTIVES: Lumbosacral transitional vertebrae (LSTV), developmental spinal canal stenosis, lumbar disc and facet joint degeneration are all common lumbar spine conditions. This study explores the relationship between these entities. METHODS: Five hundred and five patients (254 females, 251 males), mean age 57 ± 13 years, who underwent abdominopelvic CT examinations were studied. Vertebral body cross-sectional area (CSA), spinal canal CSA, width and depth were measured from L1 to L5. The presence of LSTV was documented and the severity of disc/facet joint degeneration graded. RESULTS: LSTV was present in 155 (31%) of 505 patients, being twice as common in males than in females. After controlling for age, height and weight, vertebral body CSAs from L1 to L5 in male LSTV patients were, on average, 9.8% larger than those in male non-LSTV patients (p < 0.0001 for all) while vertebral body areas at L3 and L4 were 4.5% larger in female LSTV patients than in non-LSTV female patients. Disc degeneration from L2/3 to L5/S1 and facet joint degeneration from L2/3 to L4/5 were more severe in LSTV patients. LSTV Castellvi Type II patients appear to be most prone to disc and facet degeneration. CONCLUSIONS: LSTV patients, and particularly male patients, have an increased vertebral body CSA compared to non-LSTV patients throughout the lumbar spine. LSTV patients also have more severe disc and facet joint degeneration. The increase in vertebral body area may be contributing to the increased lumbar and facet joint degeneration seen in LSTV patients. KEY POINTS • LSTV patients have increased vertebral body cross-sectional area throughout their lumbar spine compared to non-LSTV patients. This vertebral body area increase was more pronounced in male patients and also apparent in younger patients with LSTV. • LSTV patients have increased disc and facet joint degeneration affecting most of the lumbar spine than non-LSTV patients. • Increased vertebral body area may contribute to the increased lumbar disc and facet joint degeneration seen in LSTV patients.