# Lumbosacral Transitional Disorder as a Missing Link in Symptomatic Scoliosis
## 4 Discussion
Prevalence of LSTVs:  
Patients classified as Castellvi I were not included in this study because the delineation with the 19 mm width of the processus transversus was found to be too blurred. The radiological appearance of the width of the processus transversus in the radiograph depends on the pelvic tilt and the radiographic focus. In MRI examination, the imaging quality of 1.5-Tesla devices is insufficient for measurements. Even with 3.5-Tesla devices, the sectioning does not always provide clear results. Scoliosis inevitably leads to unclear results due to its curvature and rotation. A reliable classification would only be possible with a differentiated examination focused on this issue. This does not mean that patients with LSTV Castellvi I may not also have complaints due to this change. Under these conditions, the data presented cannot be compared with the prevalence of other studies. The central message of this study is that if scoliosis is present, the possibility  
Figure 4: LSTV-classification/Lenke-classification. of LSTVs should also be considered. This is especially true when scoliosis is combined with lumbar symptoms. [PERSON] et al. (2015) focus on the clinical significance of LSTVs in their review. The problem of diagnosis is also addressed as follows: \"LSTV are often inaccurately detected and classified on standard AP radiographs and MRI\" [25]. [PERSON] et al. (2021) also address the frequency distribution, noting that the complaints particularly affect Castellvi II, III, and IV [26]. [PERSON] et al. (2011) also describes the frequency distribution problem and the related high differences in individual studies [21]. The study by [PERSON] et al. describes the lumbosacral ligamentous apparatus and thus goes one step further in differentiation. However, the result requires a very high quality of MRI examination. This quality difference problem between individual radiological institutes became apparent from the beginning of their first examinations and was solved by the fact that all examinations were performed by one institute according to the agreed focus [27]. Under these conditions, the frequency distribution of LSTVs may not be directly compared with individual studies from the literature. This is certainly the main reason for the high differences in frequency distribution between individual studies. The literature: Scoliosis and LSTVs:  
The topic of scoliosis and LSTVs is the focus of the PubMed (18 April 2022) search with 13 entries. Among them, nine papers deal with the relationship of the surgical approach to scoliosis and LSTVs. In particular, they focus on the question of surgical fusion distance and adjacent disc degeneration [28; 29; 30; 31; 32; 33; 34; 35]. There are only four contributions for clinical issues related to scoliosis and LSTVs. In one paper, the incidence of LSTVs in young men in military school in Turkey is surveyed. In another paper, the number of thoracic and lumbar vertebral bodies in adolescent idiopathic scoliosis is shown. There is a paper that is also devoted to the degeneration of the adjacent vertebral segment. A final paper deals with the clinical significance of LSTVs in patients with idiopathic scoliosis [18; 19; 36; 37]. Limitation:  
In MRI examinations, there are imaging inaccuracies that depend on the angulation of the device setting to the vertebral bodies. Thus, in any lumbar scoliosis, orthograde imaging of each vertebral body is not guaranteed. Thus, blurring cannot be avoided. A CT scan would image the bony structures more accurately. For reasons of radiation hygiene, this is prohibited as a routine examination. A comparison of the frequency with other studies is not permissible since only Castellvi II-IV is considered. Another problem becomes apparent in the present work on scoliosis:  
How can LSTV Castellvi IIA be differentiated from a decompensated lumbar curve with a contact zone of the processus transversus with the os sacrum?