Hyperostosis corticalis generalisata, also known as van Buchem disease, is a rare craniotubular hyperostosis characterized by hyperostosis of the skull, mandible, clavicles, ribs and diaphyses of the long bones, as well as the tubular bones of the hands and feet. Clinical manifestations include increased skull thickness with cranial nerve entrapment causing inconsistent cranial nerve palsies. The disease is hyperostosis corticalis generalisata (MONDO_0009395). Also known as: Van Buchem disease, endosteal hyperostosis, hyperphosphatasemia tarda, van Buchem disease, van Buchem disease type 1.