Distribution and incidence of degenerative spine changes in patients with a lumbo-sacral transitional vertebra

Abstract

The purpose of this prospective study was to determine the overall incidence and distribution of lumbo-sacral degenerative changes (i.e. disc protrusion or extrusion, facet degeneration, disc degeneration, nerve root canal stenosis and spinal stenosis) in patients with and without a lumbo-sacral transitional vertebra (LSTV). The study population consisted of 350 sequential patients with low back pain and/or sciatica, referred for medical imaging. In all cases CT scans of the lumbosacral region were obtained. In 53 subjects (15%) an LSTV was found. There was no difference in overall incidence of degenerative spine changes between the two groups. We did find, however, a different distribution pattern of degenerative changes between patients with and those without an LSTV. Disc protrusion and/or extrusion occurred more often at the level suprajacent to the LSTV than at the same level in patients without LSTV (45.3% vs 30.3%). This was also the case for disc degeneration (52.8% vs 28%), facet degeneration (60.4% vs 42.6%) and nerve root canal stenosis (52.8% vs 27.9%). For spinal canal stenosis there was no statistically significant difference between the two categories. In conclusion, our findings indicate that an LSTV does not in itself constitute a risk factor for degenerative spine changes, but when degeneration occurs, it is more likely to be found at the disc level above the LSTV.

Measurement of spinal canal diameters in young subjects with lumbosacral transitional vertebra

“…In a previous study, Elster [4] demonstrated that central and lateral spinal stenosis is much more common at or near the interspace above the transitional vertebra. In contrast, a recent study conducted by Vergauwen et al [18], in which they measured the spinal canal diameters in adult patients with LBP and with or without LSTV on computed tomographic (CT) scan, found no significant difference in the distribution of spinal stenosis between the two groups.…”

“…However, the role of these radiographic abnormalities in the etiology of LBP is unclear [1,3,4,15,18,19].…”

“…A review of the literature revealed two studies [4,18] dealing with the association between spinal stenosis and LSTV. These studies differ considerably from the current study with regard to design and study population.…”

“…Second, an intervertebral disc space, even vestigial, must be presented caudal to the transitional vertebra. The terms "lumbarization" and "sacralization" were avoided [18].…”

“…The results of the few studies published on this subject showed no higher incidence of structural problems in patients with LSTV than in those without such vertebrae [1,4,19]. However, it has been suggested that there is an increase in degenerative changes such as disc protrusion, facet degeneration, nerve root canal stenosis and degenerative spondylolisthesis just above transitional lumbosacral segments [4,11,18].…”