Bilateral coronal and sagittal synostosis in X-linked hypophosphatemic rickets: a case report

Craniosynostosis can be gene-linked, or caused by metabolic diseases, such as rickets, which results from a deficiency or impaired metabolism of vitamin D, magnesium, phosphorus or calcium leading to hypomineralization of the bone. X-linked dominant hypophosphatemic rickets (XLHR) is the most prevalent genetic type of hypophosphatemic rickets and is caused by germ line mutations in the PHEX-gene. In XLHR, only few case reports of craniosynostosis were described. Here, we present a clinical report of an 18 months old child with XLHR and bilateral coronal and sagittal synostosis who was treated by subtotal cranial vault remodelling with fronto-orbital advancement and right-angled Z-osteotomies. As a consequence of the child's diminished bone regeneration capacity, surgery that is performed after the age of 1 year requires more extensive craniectomy, multiple osteotomies and rigid fixation for calvarial vault remodelling to prevent extensive bone defects.