Craniofacial Asymmetric Patterns in Congenital Muscular Torticollis: A Computed Tomography-Based Visual Classification and Cluster Analysis With Clinical Implications.

Congenital muscular torticollis (CMT) is a common postural disorder in infants, frequently accompanied by craniofacial asymmetry. Despite its prevalence, detailed characterization of the 3-dimensional (3D) craniofacial morphology in CMT remains limited. This study aimed to explore the craniofacial patterns in children with CMT using 3D computed tomography scan reconstruction and assess their relationship with clinical classifications. Forty-four children aged 5 to 92 months were included in this study. Ten craniofacial parameters were visually assessed by multiple raters, including medical and nonmedical professionals, and frontline and specialized clinicians. High reproducibility was observed for features such as mandibular tip deviation and parietal bone measurements. The sternocleidomastoid tumor and torticollis subgroups of CMT show similar craniofacial asymmetry profiles, and molded baby syndrome to a lesser extent. The postural torticollis subgroups showed different profiles. Multiple factor analysis followed by hierarchical clustering revealed 6 distinct morphologic groups that did not correspond to the clinical, sex, or age subgroups, highlighting the significant variability in craniofacial morphology in CMT. These results emphasize that imaging assessment provides complementary information but cannot replace a thorough clinical evaluation. Our study confirmed that CMT-associated craniofacial asymmetry is a 3D asymmetry that remains difficult to understand.