Lumbosacral Transitional Disorder as a Missing Link in Symptomatic Scoliosis

Abstract

Back pain in the presence of LSTVs (lumbosacral transitional vertebrae) was originally noted by Mario Bertolotti in 1917. The Lenke classification for scoliosis forms the current international standard. However, the connection between LSTVs and scoliosis is still poorly understood. The aim of this study is to show the connection between scoliosis and LSTVs in terms of their frequency and impact on further development. Our scoliosis outpatient clinic has an examination period that covers the years from 2014 to 2021. If LSTVs are radiologically suspected (AP and lateral X-ray of the spine) according to the Castellvi classification (II–IV), a further MRI investigation is initiated. Scoliosis shape is assigned according to the Lenke classification. Sagittal segmental differences are observed according to the vertical mean vertebral angle (VMVA) and its difference (Diff-VMVA). Assignment to the lumbar pain group is made in cases of a history of chronic or recurrent pain of more than 6 months. Differentiation is made at the initial presentation according to gender (male–female) and age (children and adults). Other associated diagnoses such as family correlations and the question of brace fitting are cited. Finally, the literature is reviewed from a scoliosis perspective and compared with the findings of the authors of this paper. A total of 1332 patients were evaluated, and LSTV Castellvi II–IV was confirmed in 72 of them (58 female and 14 male). The curvature extent of scoliosis in children and adults had a mean Cobb angle of 24.3° with a range from 11° to 55° (n-42) and 32.4° with a range from 12° to 66° (n-30), respectively. This indicates that 75% of n-54 patients were mostly classified as Castellvi II (pseudarthrosis) (IIA, 54.2%; IIB, 20.8%) in the total data. There were few patients classified with Castellvi III (22.2%) and IV (2.8%). A proportion of 87.5% of 72 patients were mostly classified as Lenke 1 (25.0% n-18) and Lenke 5 (62.5% n-45). According to the literature, the Diff-VMVA shows Cobb angles of 9.3° for Castellvi III and 5.3° for Castellvi IV. Half of the patients complain of chronic low back pain for at least 6 months or have recurrent complaints (48.6%). The complaints are mostly classified as Castellvi IIA (27.8%) and B (9.7%). The association of scoliosis and LSTVs yields only 13 studies (PubMed 04/18/2022) that focus on spine surgery issues and not on diagnostics. Attention should be given to the lumbosacral junction in Lenke 1 and Lenke 5. Nearly half of the patients in each category complain of chronic lumbar symptoms. This is notable in individual cases due to its rounding and thus its increased Diff-VMVA. Since only Castellvi II–IV is considered, a comparison of the frequency with other studies is not permissible. In conclusion, for scoliosis Lenke 5 and Lenke 1, the lumbosacral junction should be examined.