Adolescent Scoliosis in Autism Spectrum Disorder: Is it Idiopathic or Syndromic?

Purpose : Minimal data exists on whether adolescents with both autism spectrum disorder (ASD) and scoliosis exhibit distinct curve types or require varying surgical management compared to neurotypical adolescents. Our study at a high-volume scoliosis center compares patterns of scoliosis in ASD patients with those of neurotypical patients. We hypothesized adolescents with ASD would present with atypical scoliosis curve characteristics compared to neurotypical adolescents. Methods: Using ICD-10 codes, we constructed an electronic database of adolescents aged 10 to 18 with diagnoses of both scoliosis and ASD. To avoid confounding with syndromic conditions, adolescents with a syndrome independently associated with scoliosis were excluded. Additionally, a 1:2 matched cohort analysis was performed to compare adolescents with ASD and scoliosis (ASD-S) to neurotypical individuals diagnosed with adolescent idiopathic scoliosis (AIS). Results: In our study, we describe demographics, radiographic characteristics, and complications experienced by 37 patients with both scoliosis and ASD. Almost half of ASD-S patients (18/37 patients; 48.6%) exhibited sagittal plane abnormalities. In comparison to the matched cohort of neurotypical patients, ASD-S patients had increased T5-12 thoracic kyphosis (31.6 vs. 24.4 degrees, p=0.005), maximum thoracic kyphosis (36.8 vs. 30.9 degrees, p=0.040) and lumbar lordosis (50.9 vs. 46.1 degrees, p=0.043). Sagittal vertical axis ≥ 5 cm was more prevalent in ASD-S patients than patients with AIS (p=0.015). Furthermore, ASD-S patients were more likely to demonstrate an abnormal trunk shift (46% versus 19%) compared to the neurotypical cohort. Social and behavioral barriers prevented three ASD-S patients (8%) and no patients with AIS who were indicated for posterior spinal fusion from undergoing the procedure. Conclusion : ASD-S patients had increased thoracic kyphosis compared to both controls and published AIS norms, suggesting scoliosis in ASD could potentially be considered a form of syndromic scoliosis rather than truly idiopathic. Additionally, the impact of social and behavioral barriers must be considered when treating this patient population. Level of Evidence: III