Block vertebra: fusion of axis with the third cervical vertebra – a case report

Skeletal abnormalities at the craniocervical junction or cervical region may result in severe neck pain and sudden unexpected death. During the osteology demonstration of cervical vertebrae for the MBBS Phase I students at M. S. Ramaiah Medical College, it was observed that the axis vertebra is fused with the 3rd cervical vertebra. In this case, the vertebral bodies, vertebral arches and spines were completely fused. This is a condition of block vertebra which has embryological importance and clinical implications.