Lumbosacral Transitional Vertebra-Related Low Back Pain: Resolving the Controversy

STUDY DESIGN: Case control study. PURPOSE: The association of lumbosacral transitional vertebra (LSTV) with low back pain (LBP) is controversial, as is the role of occupational physical activity and radiological spinal abnormalities suggestive of other spinal disorders (OSDs) such as spinal degeneration and instability. This study aimed to determine if any association of LSTV with LBP exists. If so, the association of the level of physical activity and presence of OSD with LSTV-related LBP was determined. OVERVIEW OF LITERATURE: The cause of LBP has been linked to proximal level disc degeneration, arthritic pseudoarticulation between LSTV and the sacral ala, facet joint degeneration, and nerve root compression due to a broadened transverse process. LSTV associated with LBP is present among individuals who are involved in high-level physical activity, including military recruits and athletes. METHODS: This was an unmatched study comprising 372 cases and 224 controls consecutively recruited with clinical and radiographic documentation. The relationship between LSTV and LBP was analyzed, and the effects of LSTV and OSD on this relationship were also assessed and statistically controlled. RESULTS: The presence of LSTV (p =0.039) was significantly associated with LBP, and the presence of OSD was associated with LTSV-related LBP, after statistically controlling for the level of physical activity (p =0.024). The level of physical activity was not associated with LBP. Demographic analysis revealed female predominance with an advanced age (>45 years) among those with LSTV-related LBP who have OSD. CONCLUSIONS: The presence of LSTV was associated with an increased prevalence of LBP. This association was probably due to the confounding effect of OSD. The level of occupational physical activity was not associated with LSTV-related LBP. We speculate that advanced age and female sex caused the spurious association of LSTV with LBP in our study, rendering LSTV-related LBP controversial in published literature.