title: Os odontoideum in identical twins: perspectives on etiology.
abstract: Most authorities favor the hypothesis of an acquired etiology of os odontoideum. We present the cases of identical twin sisters with os odontoideum in association with a congenital partial fusion of the posterior elements of the second and third cervical vertebrae, and discuss the implications. We believe that this is the first report of familial os odontoideum in a context which suggests a genetic etiology.
authors.affiliation: Department of Radiological Sciences, UCLA School of Medicine 90024-1721.
authors.forename: K A
authors.initials: KA
authors.lastname: Kirlew
authors.forename: G M
authors.initials: GM
authors.lastname: Hathout
authors.forename: S D
authors.initials: SD
authors.lastname: Reiter
authors.forename: R H
authors.initials: RH
authors.lastname: Gold
mesh_terms: D000328:Adult; D001268:Atlanto-Axial Joint / Q000002:abnormalities*; D002574:Cervical Vertebrae / Q000002:abnormalities; D004200:Diseases in Twins; D005260:Female; D006801:Humans; D009809:Odontoid Process / Q000002:abnormalities*