Introduction and objective:
Deformational (non-synostotic positional) plagiocephaly is a frequent craniofacial asymmetry in infants caused by prolonged external pressure on the neonatal skull. It may lead to motor delays, postural asymmetries and neurodevelopmental issues. Osteopathic manipulative treatment (OMT) is used as a gentle, non-invasive approach to improve cranial symmetry and support development. The aim of this systematic review is to evaluate the effectiveness and safety of OMT in infants under 12 months with non-synostotic positional plagiocephaly.

Review methods:
Six clinical studies (two RCTs, one large cohort, one outcome research, one chart review and one pilot study) assessing OMT with validated anthropometric measures (ODDI, CVAI, CVA) were included. Methodological quality was evaluated using the Downs and Black checklist.

Brief description of the state of knowledge:
OMT was typically delivered in 3–6 sessions. Most studies showed significant or clinically relevant reductions in cranial asymmetry. Benefits were observed in both therapeutic and preventive settings. High parental satisfaction and excellent safety (no adverse events) were consistently reported.

Summary:
Available evidence indicates that OMT is a safe and potentially effective complementary intervention for non-synostotic positional plagiocephaly in infants. Early application may improve cranial symmetry and support neurodevelopment. However, due to heterogeneity, small samples and limited long-term data, high-quality multicentre RCTs are required to confirm these findings.