Vestibular Morphological Alterations in Adolescent Idiopathic Scoliosis: A Systematic Review of Observational Studies

Abstract

Adolescent idiopathic scoliosis (AIS) is the most frequent pediatric spinal deformity. Its treatment still shows limited results due to the existent lack of knowledge regarding etiopathogenesis. Thus, the purpose of the study is to check the existence of vestibular morphological alterations among idiopathic scoliosis patients. To meet the objective, we performed this systematic review searching studies in PubMed Medline, SCOPUS, Web of Science, CINAHL Complete and SciELO until 15 September 2022. Articles that analyzed the morphology of the vestibular apparatus were selected, comparing subjects with AIS versus healthy subjects. Variables were selected that measured the orientation of the channels as well as the general conformation of the vestibular apparatus. One hundred and eighty-five records were retrieved in the preliminary searches, of which five studies were finally included, providing data from 154 participants (83 cases and 71 healthy controls) with a mean age 16.07 ± 2.48 years old. Two studies conclude that the superior and lateral semicircular canals are longer and thinner in patients with AIS. One study concluded that the measure between centers of superior and lateral canals and the angle whose vertex is placed the center of posterior canal were significantly shorter in subjects with AIS than in healthy controls in the left-side of vestibular apparatus. Two studies found an asymmetry in the verticality of the lateral canals on both sides in subjects with AIS, although it is not clear whether the left canal is in a more horizontal or vertical position. Patients with AIS seem to present morphological asymmetries of the vestibular apparatus, fundamentally on the left side. These anomalies seem to correlate with the location of the curve but not with its laterality or severity.

Idiopathic scoliosis in subjects with eye diseases: A systematic review with meta‐analysis

“…Recently, a review found that IS subjects appear to show structural abnormalities of the vestibular apparatus. 8 This could compromise the perception of the subject's gravitational verticality 44 and cause an alteration of self-image. 51 These works have speculated that spinal curvature could develop in response to an inappropriate postural pattern.…”

“…1 A better understanding of what causes this spinal malformation would facilitate improvement of the approaches to reduce sequelae. 8 To date, authors have found relationships between IS and several conditions: structural alterations during growth, 9…”

“…There is no consensus concerning its etiology; hence, treatment is focused on stopping the progression of the curvature by the use of braces and/or therapeutic exercises, although sometimes when the curve passes 40°, surgery is required for aesthetic and functional reasons 1 . A better understanding of what causes this spinal malformation would facilitate improvement of the approaches to reduce sequelae 8 . To date, authors have found relationships between IS and several conditions: structural alterations during growth, 9 geographical latitude and its influence in menarche, 10,11 plagiocephaly, 12 melatonin receptor polymorphism, 13 alterations in calcium–phosphorus balance, 14 morphological 8 or functional alterations in the vestibular system, 15 neurological findings (presumably harmless), 16 and orthodontic abnormalities 17 .…”

“…A better understanding of what causes this spinal malformation would facilitate improvement of the approaches to reduce sequelae 8 . To date, authors have found relationships between IS and several conditions: structural alterations during growth, 9 geographical latitude and its influence in menarche, 10,11 plagiocephaly, 12 melatonin receptor polymorphism, 13 alterations in calcium–phosphorus balance, 14 morphological 8 or functional alterations in the vestibular system, 15 neurological findings (presumably harmless), 16 and orthodontic abnormalities 17 . Most authors consider IS to be multifactorial, involving genetic, tissular, hormonal, biomechanical, and neurosensorial factors 18 …”

Is there a link between scoliosis and headache disorders-related symptoms?

“…As regards other types of headache that may be present in patients with scoliosis and be correlated with the same deformity, the study by Uneri brings into focus vestibular migraine (27). Vestibular disorders and migraines are characterized by a high prevalence in general population; there are some studies and in particular Cortes-Perez (28) which highlight the association between scoliosis and alterated vestibular morphology (29).…”