Familial vertebral segmentation defects, Sprengel anomaly, and omovertebral bone with variable expressivity.

A 10-year-old boy was found to have an unusual presentation of the Sprengel anomaly, omovertebral bones, and segmentation defects of the vertebral column at the cervical, thoracic, and sacral level. In addition, he showed hypertelorism, downslanting palpebral fissures, ptosis, webbing, and hypoplasia of the thenar and hypothenar areas. He had moderate mental delay. In addition to the segmentation defects and omovertebral bones, radiological studies showed a small pelvis and 11 pairs of ribs. Some of the features were present in the mother, and minimal symptoms were present in the father. The parents were consanguineous. A paternal cousin had segmentation defects, omovertebral bones, and a Sprengel deformity as well, although with milder presentation than the proband. We were unable to find a similar combination of manifestations in literature. The familial occurrence is best compatible with autosomal dominant inheritance, showing wide variability of expression. It is possible that the more notable signs in the proband can be explained by homozygosity for the disorder.