Vertebral anomalies in monozygotic twins.

In an 8-year-old pair of monozygotic twins a T8 butterfly vertebra was found in one and a coronally cleft T8 vertebra in the other. Differential diagnostic possibilities include trauma, Scheuerman's disease, tuberculosis, and infiltrative disorders, such as Gaucher's disease and malignancies. The literature however, describes them as separate entities. A common congenital origin for both lesions is discussed and the literature reviewed.