A Japanese Patient With Craniosynostosis Due to X-Linked Hypophosphatemic Rickets Who Underwent Fronto-Orbital Distraction.

X-linked hypophosphatemic rickets (XLHR) is caused by loss-of-function mutations in the phosphate-regulating endopeptidase homolog X-linked gene (PHEX). Secondary craniosynostosis is one of the complications of XLHR. Early fusion of the coronal, frontal, and sagittal sutures was noted at 11 months of age in an infant diagnosed with XLHR. A fronto-orbital distraction was performed at 14 months of age to increase cranial morphology and intracranial volume. Although the surgical approach utilized distraction osteogenesis, a fronto-orbital fragment was first removed, reshaped, and then a fronto-orbital distraction was performed due to the extensive fusion of the cranial sutures and significant deformity. Postoperatively, new bone formation took somewhat longer than expected due to the nature of the disease. However, bone formed without major issues, the cranial cavity expanded significantly, and a favorable cranial morphology was achieved. Distraction osteogenesis is a more reliable technique because tissue is progressively stretched with a gradual extension of soft tissue as well. Distraction osteogenesis remains an effective treatment option even for craniosynostosis caused by bone disorders like XLHR.