Prevalence of lumbosacral transitional vertebra in patients with chronic low back pain: a descriptive cross-sectional study.

Am J Neurodegener Dis 2023;12(3):89-96 www.AJND.us /ISSN:2165-591X/AJND0150535 Original Article Prevalence of lumbosacral transitional vertebra in patients with chronic low back pain: a descriptive cross-sectional study Surendra Kumar Jat, Amit Srivastava, Raskesh Malhotra, Manish Chadha, Anupama Tandon, Anil K Jain Department of Orthopaedics, University College of Medical Sciences and Guru Teg Bahadur Hospital, Delhi, India Received April 4, 2023; Accepted June 9, 2023; Epub June 15, 2023; Published June 30, 2023 Abstract: Background: Numerous causes of low back pain have been identified like spondylosis, spondylolysis, spondylolisthesis, facet lesions, discal abnormalities, vertebral instability, degenerative osteoarthritis, etc., These causes of low back pain are seen commonly in >50 years of age. Lumbosacral transitional vertebra (LSTV) is a common congenital anomaly with multitude of intermediate morphologic manifestations between the typical sacral and lumbar vertebra reported by some authors as a cause of low back pain. There are racial differences reported in the literature on the prevalence of LSTV. There is no common consensus in literature about the association between LSTV and low back pain. There is a paucity of literature on the subject in the Indian population, hence the current study was conducted. Material and methods: 60 cases of low back pain and 60 controls were included in the study. Patients between 18-50 years of age with low back pain of >12 weeks duration who were fulfilling the inclusion criteria were included in the study. The plain radiographs were screened by two observers (one Orthopaedician and one Radiologist) for the presence or absence of lumbosacral transitional vertebra (LSTV) and classification was determined by consensus. The incidence of LSTV was calculated in both the groups (cases and controls) and evaluated for statistical significance. Results: Prevalence of lumbosacral transitional vertebra (LSTV) was found to be 38.33% in cases group as compared to control group (21.66%) and was statistically significant (p value <0.05). Prevalence of lumbarisation was higher in case group (10%) in comparison to control group (5.0%) but not found to be statistically significant. Prevalence of sacralisation was also found to be higher in case group (28.33%) as compared to control group (16.67%). This was not found to be statistically significant. Conclusion: The present study showed a higher prevalence of lumbosacral transitional vertebra (LSTV) in case group (38.33%) as compared to control group (21.66%) which was found to be statistically significant. Prevalence of lumbarisation and sacralisation were both found to be higher in the case group in comparison to control group, but the difference was not statistically significant. However, further studies with larger sample would be needed to conclusively determine any association between low back pain and subtypes of LSTV. Keywords: Back pain, sacralisation, lumbarisation, plain radiographs, transitional vertebra, prevalence Introduction Low back pain is a very common problem that most people experience in their lifetime [1-4]. Numerous causes of back pain have been identified in >50 yrs. of age, like spondylosis, spondylolysis, spondylolisthesis, facet lesions, discal abnormalities, vertebral instability, degenerative osteoarthritis, etc., but in young patients the exact cause of low back pain is often unclear [5, 6]. Lumbosacral transitional vertebra [LSTV] is a common congenital anomaly. In this either the fifth lumbar vertebra may show assimilation with the sacrum (sacralization), or the first sacral vertebra may show transition to a lumbar configuration (lumbarisation) [7]. Castellvi et al. [8] classified LSTV into 4 type (Figure 1) based on their morphologic and clinical characteristics concerning herniated nucleus pulposus. TYPE 1 - Dysplastic transverse process; unilateral [a] or bilateral [b]. Large triangular transverse process, measuring at least 19 mm in width, in this type location of herniated nucleus Lumbosacral transitional vertebra in chronic low back ache to type 2 except that instead of the di-arthrodial joint between the transverse process and the sacrum, there is true bony union. TYPE 4 - Mixed; type 2 on one side and type 3 on the other side. In type 3 and type 4, there are similar distributions of herniation as shown in the normal population. And also, there is no herniation at the level of transition. It has been reported that people with LSTV are more prone to develop back pain [9-11]. The various etiologies of low back pain in LSTV can be; degeneration of anomalous articulation between an LSTV and the sacrum [12], disc, spinal canal, and posterior element pathology at the level above a transition [13], extraforaminal stenosis secondary to the presence of broadened transverse process of the transitional vertebra [14], decrease paraspinal muscle volume and increased lumbar lordosis [15], facet joint arthrosis contralateral to a unilateral fused or articulating LSTV [12]. There are racial differences reported in the literature on the prevalence of LSTV. The prevalence in the Western population is reported between 12% to 30% [7, 9, 10, 16-20], in Chinese population it is reported to be 4% [21] and 4-19% in few Indian studies [22-25]. In general population the prevalence of lumbarisation reported is 3.4-7.2% whereas sacralization is 1.7-14% [26]. The incidence of LSTV is found to be more in males than females [18]. Figure 1. Diagrammatic representation of LSTV classification according to Castellvi et al. [8]. pulposus was not different from that seen in the normal population. TYPE 2 - Incomplete lumbarisation/sacralisation; unilateral [a] or bilateral [b]. In this type, enlarged transverse process, which appears to follow the contour of the sacral ala. They are considered incomplete because there appears to be a di-arthrodial joint between the transverse process and the sacrum. In this type incidence of herniation just above transition was 83.4%. TYPE 3 - Complete lumbarisation/sacralisation; with unilateral [a] or bilateral [b], this is similar 90 There is no common consensus in literature about the association between LSTV and low back pain. There is a paucity of literature on the subject in the Indian population, hence the current study was conducted to find out prevalence of lumbosacral transitional vertebra in Am J Neurodegener Dis 2023;12(3):89-96 Lumbosacral transitional vertebra in chronic low back ache Table 1. Inclusion and exclusion criteria Inclusion criteria ● Cases; Patients between 18-50 years with a complaint of chronic lower back pain of >12 weeks duration. ● Controls: Patients between 18 yrs. - 50 yrs. of age, who underwent X-ray KUB (Kidney and Urinary Bladder) for complaints other than low back pain. patients with chronic low back pain in the Indian population. Material and methods Patient enrollment criteria After approval by the Institutio (...truncated)