Abstract #1955

Congenital Malformations of Occipital Vertebrae as Cause of Instability and Degeneration of Atlanto-Axial Joints

Carolina Medeiros Rimkus^1,2, Vernica Arajo Zanardi³, Alberto Cliquet Jr²

¹Radiology and Diagnostic Imaging, State University of Campinas, Sao Paulo, SP, Brazil; ²Orthopaedics Department, State University of Campinas, Campinas, SP, Brazil; ³Radiology and Diagnostic Imaging, State University of Campinas, Campinas, SP, Brazil

Some aspects of the craniocervical junction malformations are trully congenital. But the chronical instability and the articular overload imposed by the skeletal deformities add biomechanical disturbances that can be correlated to acquired disorders. 20.7% of the patients presented atlanto-axial subluxation, correlated to morphological abnormalities classified as manifestations of the occipital vertebrae. Signals of degeneration of the atlanto-axial joints were shown in 42.6%, correlated to atlanto-occipital assimilation.