Idiopathic scoliosis: a systematic review and meta-analysis of heritability

Abstract

Purpose Idiopathic scoliosis is the most common spinal deformity and affects 1–3% of children and adolescents. Idiopathic scoliosis may run in families and the purpose of this systematic review was to describe the degree of heritability. Methods We searched Medline, Web of Science and EMBASE for family and twin studies reporting heritability estimates for idiopathic scoliosis, or studies from which heritability estimates could be calculated. Reference lists were screened for additional papers. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The protocol was registered at PROSPERO (registration number: CRD42022307329). Results The literature search identified 1134 reports. After full-text screening, nine eligible reports were included for data extraction. Seven were twin studies containing between 5 and 526 pairs, and two were family studies with 1149 and 2732 individuals, respectively. Quality was ‘good’ in four studies and ‘fair’ in five studies. In general, studies with radiograph-confirmed diagnosis reported higher heritability estimates than studies with self-reported diagnosis. Population-based twin studies reported lower heritability estimates than clinic-based twin studies. Family-based studies reported higher heritability estimates than twin studies. Pairwise concordance for scoliosis ranged from 0.11 to 1.00 in monozygotic twins and from 0 to 1.0 in dizygotic twins. A meta-analysis of three studies resulted in a narrow sense heritability estimate of 0.57 (95% CI: 0.29–0.86). Conclusion Twin and family studies indicate a hereditary component in idiopathic scoliosis, but study heterogeneity is large, and the degree of the heritability is uncertain. Nevertheless, known genetic variants associated with idiopathic scoliosis can still only explain a minor part of heritability.

Neuromuscular Scoliosis: A Narrative Review

“…During the initial assessment it is very crucial to distinguish the static pathological conditions and etiologies of neuromuscular scoliosis, such as myelomeningocele or cerebral palsy, from the gradually progressing and worsening pathologies (for example Duchenne dystrophy or spinal muscular atrophy). In addition, the age of the onset of the spinal deformity should be recorded in detail, in order to differentiate neuromuscular scoliosis from adolescent idiopathic scoliosis, which, in the vast majority of cases occurs at an older age 8 .…”