Atlanto-axial segmentation defects and os odontoideum in two male siblings with opsismodysplasia

We report two siblings aged 11 and 7 years, respectively, who presented with the clinical and radiographic features of opsismodysplasia (non-lethal type). 3D computed tomography scans of the craniocervical region revealed a split atlas and os odontoideum in both siblings. To the best of our knowledge, this is the first clinical report detailing craniocervical malformations in two siblings with opsismodysplasia. © 2008 ISS.