ObjectiveThis study aimed to investigate the impact of helmet therapy on changes in cranial asymmetry of infants with positional cranial deformities and to identify clinical and morphometric factors associated with treatment outcome.DesignThis retrospective monocentric cohort study included 455 infants treated between 2011 and 2021.SettingData were collected using manual measurements in a tertiary care setting within the outpatient clinic of a maxillofacial surgery department in Germany.PatientsInfants with positional cranial deformities, including plagiocephaly, brachycephaly, and combined types, were included.InterventionAll patients were treated with a helmet orthosis, and data were analyzed to assess changes in cranial measurements and associated factors.Main Outcome MeasuresPredefined outcome thresholds based on cranial asymmetry reduction and prognostic factors.ResultsPlagiocephaly was the most common deformity in 332 infants. Increased ear shift (Exp(B) = 0.199; 95% CI: 0.087-0.451; p ≤ .001) and large initial diagonal difference (Exp(B) = 0.518; 95% CI: 0.334-0.802; p = .003) were correlated to unfavorable outcome. Delayed treatment was associated with lower reduction in diagonal difference (rs = -0.229; p ≤ .001), and recognized as a negative prognostic factor (Exp(B) = 0.993; 95% CI: 0.989-0.997; p ≤ .001). In contrast, a higher baseline cranial index increased the probability of success (Exp(B) = 1.057; 95% CI: 1.030-1.084; p ≤ .001).ConclusionEarly diagnosis and intervention are crucial for effective treatment of cranial deformities with helmet orthosis, especially in cases with ear shift or severe initial deformation.
Keywords: anthropometry; brachycephaly; cranial deformities; cranial orthoses; nonsynostotic; plagiocephaly.