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.