Butterfly vertebra is a type of vertebral anomaly that results from the failure of fusion of the lateral halves of the vertebral body because of persistent notochordal tissue between them.
May be associated with lipomyelomeningocele.
An anterior spina bifida, with or without an anterior meningocele can be part of the Alagille syndrome
Jarcho-Levin syndrome
Radiograph
There is widening of the affected vertebral body. The bodies above and below the butterfly vertebra adapt to the altered intervertebral discs on either side by showing concavities along the adjacent endplates.
Some bone bridging may occur across the defect which usually happens in the thoracic or lumbar segments of the spine.