A medieval example of a sagittal cleft or ‘butterfly’ vertebra

A mature adult medieval male with a rare congenital anomaly, a sagittal‐cleft or butterfly vertebra, is presented. Clinical cases are frequently associated with axial as well as soft‐tissue defects. The present case, based only on skeletal evidence, appears to be an isolated finding. The aetiology of the clefting is outlined and palaeopathological evidence for the condition is included. Copyright © 2003 John Wiley & Sons, Ltd.