Sclerosing bone dysplasias: neurologic assessment and management.

PURPOSE OF REVIEW: Sclerosing bone dysplasias are rare genetic disorders of bone remodeling in which excessive bone formation takes place, resulting in encroachment on neural structures. The infant usually appears normal at birth, and the first sign of a problem only comes when a neurologic deficit develops, usually in the form of an acute facial palsy. Although less than 300 cases have been published, these conditions should always be considered in the differential diagnosis of facial nerve palsy, especially in children.

RECENT FINDINGS: This review highlights the neurologic presentation and assessment as well as the management of sclerosing bone dysplasias. An exciting development is the recent discovery of the sclerosteosis (SOST) gene, which is involved with excessive bone formation in sclerosteosis and Van Buchem disease. Researchers in bone metabolism and pharmaceutical companies are now utilizing this knowledge to develop a medicine for osteoporosis.

SUMMARY: In children and young adults an acute facial palsy, especially if it is recurrent, as well as a conductive hearing loss may be the first sign of a sclerosing bone dysplasia.