Find in Library

During the routine osteology demonstration for the first year MBBS students, the authors came across the presence of incomplete posterior arch in one of the atlas. Congenital clefts and other developmental anomalies of the atlas are rarely encountered. They are incidental findings discovered while investigating the cervical spine following trauma. Differentiation of developmental variants of the atlas from the Burst fracture of Jefferson is essential to prevent unnecessary medical intervention. Posterior midline cleft of atlas/ rachischisis/spinabifida occulta are well recognized and attributed to the defect /absent development of cartilaginous preformation of the arch and not to the disturbance of the ossification.