Congenital Muscular Torticollis as a Potential Neonatal Marker of Autism Spectrum Disorder and Other Neurodevelopmental Conditions.

Abstract

Background: Early intervention consistently improves developmental outcomes in children with autism spectrum disorder (ASD) and related conditions, underscoring the importance for timely recognition. Identifying early markers of atypical neurodevelopment is therefore critical. Congenital muscular torticollis (CMT), unilateral shortening of the sternocleidomastoid muscle causing infant head tilt, shares prenatal and perinatal risk factors with ASD and other developmental abnormalities. This overlap suggests that CMT may signal early disruption in neural development, potentially enabling earlier surveillance and intervention. However, large-scale evidence is scarce.

Methods: We used electronic records (live births 2005-2018; follow-up through 2024) from a large Israeli Health Maintenance Organization (HMO) to match 14,150 infants diagnosed with CMT by six months of age with unexposed peers. ASD and related conditions were ascertained via validated algorithms. Upper-respiratory and gastroenteritis infections served as negative control outcomes. Early physical therapy was examined as a potential effect modifier.

Results: Children with CMT had increased odds of ASD (odds ratio [OR]=1.25, 95% CI: 1.08-1.45) and developmental language disorder (1.25, 1.16-1.34), relative to unexposed peers. These associations persisted after accounting for maternal and perinatal factors, were absent for the negative control outcomes, and were stronger, though less precise, in infants who received physical therapy.

Conclusion: CMT is associated with elevated risks for later atypical neurodevelopment. The results suggest a possible etiological link between abnormal neural circuit maturation and musculoskeletal development. Although CMT is often considered benign in infancy, it may represent an early clinical marker of neurodevelopmental vulnerability, highlighting an opportunity for earlier recognition and intervention.