Unilateral Versus Bilateral Fronto-Orbital Advancement in Non-Syndromic Unicoronal Craniosynostosis: A Systematic Review and Pooled Data Analysis.

Abstract

Nonsyndromic unicoronal craniosynostosis (NS-UCS) is characterized by asymmetric craniofacial deformity and remains one of the most challenging entities in craniofacial surgery. Fronto-orbital advancement (FOAR) may be performed either unilaterally or bilaterally, yet the optimal approach remains controversial. The present study aims to compare surgical outcomes, complication profiles, and long-term stability between unilateral and bilateral FOAR to clarify selection criteria for surgical technique. A systematic review was conducted using the PubMed, Web of Science, and Cochrane databases, following PRISMA guidelines. Studies involving nonsyndromic anterior plagiocephaly treated by unilateral or bilateral FOAR with ≥12 months of follow-up were included. Twenty studies encompassing 511 patients met the inclusion criteria. Data were pooled, and statistical analyses were performed using (IBM SPSS Statistics version 29.0; IBM Corp., Armonk, NY) and Python-based analytical tools. Of the included patients, 315 (61.6%) underwent bilateral FOAR and 196 (38.4%) underwent unilateral FOAR. Contour deformity was significantly more frequent after unilateral FOAR (75.0% vs. 27.5%, P<0.05). Due to heterogeneous reporting across studies, postoperative strabismus outcomes could not be reliably compared using pooled analysis. Bilateral procedures required longer operative times (213 vs. 162 min, P<0.05), though no significant differences were found in overall complication rate, hospital stay, or relapse incidence between the 2 groups. Both unilateral and bilateral FOARs provide effective correction of craniofacial asymmetry in NS-UCS, but they differ in their complication profiles. Unilateral FOAR offers reduced surgical exposure and shorter operative duration but has a higher rate of contour irregularities. Bilateral FOAR achieves more comprehensive orbital and forehead correction, albeit with longer operative times and broader surgical exposure. These results suggest that the choice of technique should be guided by deformity severity, contralateral asymmetry, and surgeon experience. The analysis identifies critical data gaps in reporting relapse and revision rates, underscoring the need for prospective studies with standardized outcome measures to refine surgical algorithms for anterior plagiocephaly.