Prevalence of Lumbosacral Transitional Vertebra in Individuals with Low Back Pain: Evaluation Using Plain Radiography and Magnetic Resonance Imaging

Abstract

Study DesignDescriptive cross-sectional study.PurposeTo determine the frequency of lumbosacral transitional vertebrae (LSTV) in patients with low back pain (LBP) and the role of iliolumbar ligament (ILL) origin from L5 in LSTV cases.Overview of LiteratureTransitional vertebrae are developmental variants of the spine. LSTV is a common congenital abnormality, and failure to recognize this anomaly may result in serious consequences during surgery.MethodsAll patients aged 11–90 years of either gender with LBP for any duration, who presented for X-ray and magnetic resonance imaging (MRI) of the lumbosacral spine, were included. X-rays of the lumbosacral spine in anteroposterior and lateral views were acquired. In addition, T1- and T2-weighted sagittal and axial MRI was performed. Images were evaluated on a workstation.ResultsOf 504 patients, transitional vertebrae were observed in 75 patients (15%). Among them, 39 (52%) patients had Castellvi type III and 36 (48%) patients had Castellvi type II. However, on MRI, 42 (56%) patients had O'Driscoll type II, 18 (24%) patients had O'Driscoll type IV, and 15 patients (20%) had O'Driscoll type III. ILL origin from L5 was significantly higher (n=429, 100%) among patients with a normal lumbosacral junction than among patients with a transitional lumbosacral junction (n=22, 29.3%) (p<0.001).ConclusionsLSTV occurs at a high frequency in patients with LBP. Furthermore, in the presence of LSTV, the ILL is not a reliable marker for the identification of L5.

Evaluation of spinal-paraspinal parameters to determine segmentation of the vertebrae

“…According to the results of our study, LSTV is quite common (9%). Previous studies have found higher percentages of LSTV (10.6-18.6%) [11][12][13][14][15][16][17]. Sacralisation was more common than lumbarisation, which is consistent with other studies (4.8% vs. 4.1%, respectively) [11,14].…”

“…Similar to previous studies, the most common morphology of S1-2 intervertebral disc in the normal group was type 2 [17,19]. However, in some studies, the type 3 disc is most common in normal cases [20].…”

“…type 3 morphology) [20]. Some studies differentiate the LSTV according to the O'Driscoll classification without separating LSTV into sacralisation and lumbarisation [17]. According to the results of our study, this distinction is critical in the O'Driscoll classification.…”

“…Although it was not statistically significant, LSTV was slightly more common in women in our study (54% vs. 46%). However, in the literature, LSTV is more common in men [17]. Lumbarisation was seen equally in women and men (n = 3).…”

“…There are studies suggesting that ILL extends from L5 vertebrae in all normal cases [20]. It was observed that ILL may extend from other vertebrae than L5 in patients with LSTV [17,20,22]. In the literature, the origin of ILL from the L5 vertebra is significantly higher in normal cases than in patients with LSTV [16,17,20,24].…”