An autosomal recessive form of craniotubular hyperostosis due to loss-of-function mutation(s) in the SOST gene, encoding sclerostin. Clinical features include tall stature, enlarged jaw and facial bones, and cranial nerve compression leading to hearing loss and facial palsy. About two-thirds of patients have syndactyly and/or nail malformations. Increased intracranial pressure due to the thickened calvaria and skull base can occur. [ ]