Association between plagiocephaly and hemifacial microsomia

Fifteen of 155 patients with hemifacial microsomia were noted to have frontal plagiocephaly. These patients were examined to determine whether the frontal flattening was either secondary to deformation, the result of unilateral coronal synostosis, or part of the spectrum of hemifacial microsomia. The patients were categorized as having deformational versus synostotic frontal plagiocephaly by documenting position of the supraorbital rims, nasal root, ears, malar eminences, chin point, and the palpebral fissure height. Other extracraniofacial anomalies were also noted. Fourteen of 15 (93%) patients had characteristic deformational abnormalities. Only 1/15 (7%) had an elevated orbit, suggestive of unilateral coronal synostosis, but this diagnosis was not radiographically confirmed. Frontal deformational plagiocephaly was ipsilateral to the side predominantly affected by hemifacial microsomia in all but one patient. Patients with hemifacial microsomia-deformational frontal plagiocephaly often had ipsilateral torticollis, cervical spine abnormalities, and anomalies outside the craniofacial region. This was in contrast to patients with deformational frontal plagiocephaly, in the absence of hemifacial microsomia, who frequently had ipsilateral torticollis but no other anomalies. This study also underscores possible confusion in differentiating hemifacial microsomia from deformational hemifacial hypoplasia on physical examination. The association of deformational frontal plagiocephaly and hemifacial microsomia belies a rigid etiologic label of deformational versus malformative anomaly.