HEMIVERTEBRAE

· Half of the vertebral body develops resulting in a scoliosis or kyphoscoliosis.

· Hemivertebrae result from “hemimetameric displacement of the somites during the recombination of sclerotoms to form primordial vertebrae”.

· They are wedge shaped vertebrae and the apex may point dorsally, ventrally or medially.

· A defect in the development of the vascular supply can result in failure of ossification of half of the vertebral body and may cause unilateral hemivertebrae or dorsal or ventral hemivertebrae.

• Sporadic or as part of a syndrome.

ULTRASOUND

• Absence of half of the vertebral body.
• Scoliosis at the site of the defect.
• Associated anomalies include:
• Anomalies of the ribs, limbs or elsewhere in the spinal cord.
• Gastrointestinal, genitourinary or central nervous system anomalies.

REFERENCES

1. Benacerraf BR, Greene MF, Brass VA. Prenatal diagnosis of congenital hemivertebra. J Ultrasound Med 1986;5:257.
2. Abrams SL, Filly RA. Congenital vertebral malformations: prenatal diagnosis using ultrasonography. J Ultrasound Med 1986;5:257.