Hemivertebra¶

Definition¶

A hemivertebra is a congenital anomaly of vertebral formation that results from unilateral failure of half of the vertebral body to form. This results in a wedge-shaped vertebral body that produces lateral curvature (congenital scoliosis) or kyphosis depending on its location and whether it is segmented or unsegmented.

Classification¶

By Segmentation¶

• Fully segmented — Normal disc spaces above and below the hemivertebra. This type has the highest growth potential and is most likely to cause progressive deformity.
• Semi-segmented — A disc space on one side but fusion to an adjacent vertebra on the other side. Moderate growth potential.
• Non-segmented (incarcerated) — Fused to the vertebrae above and below on both sides. Limited growth potential — least likely to cause progressive deformity.

By Location¶

• Lateral — Produces congenital scoliosis
• Posterior — Produces congenital kyphosis (more dangerous because of potential for cord compression)
• Posterolateral — Produces kyphoscoliosis

Imaging Findings¶

Radiography/CT¶

• Wedge-shaped vertebral body with a contralateral body deficiency
• Associated curvature (scoliosis or kyphosis)
• Evaluate the disc spaces above and below to classify segmentation status
• May be associated with contralateral bar (unsegmented bar + hemivertebra is the worst combination for progressive deformity)

MRI¶

• Evaluates the spinal cord for associated anomalies (diastematomyelia, tethered cord, syringomyelia)
• Cord compression from kyphotic hemivertebra
• All patients with congenital scoliosis should have MRI to exclude intraspinal anomalies before surgical correction

Key Points¶

• Congenital anomaly of vertebral formation — only one half develops
• Fully segmented hemivertebrae have the highest growth potential
• Associated spinal cord anomalies in up to 25% — MRI is mandatory
• Contralateral bar + hemivertebra is the worst combination for progressive deformity
• Posterior hemivertebra causing kyphosis is more dangerous than lateral (scoliosis)

References¶

1. Johal J, Loukas M, Fisahn C, Chapman JR, Oskouian RJ, Tubbs RS. Hemivertebrae: a comprehensive review of embryology, imaging, classification, and management. Childs Nerv Syst. 2016;32(11):2105-2109. doi:10.1007/s00381-016-3195-y. PMID: 27449768.
2. McMaster MJ, Ohtsuka K. The natural history of congenital scoliosis. A study of two hundred and fifty-one patients. J Bone Joint Surg Am. 1982;64(8):1128-1147. PMID: 7130226.
3. Belmont PJ Jr, Kuklo TR, Taylor KF, Freedman BA, Prahinski JR, Kruse RW. Intraspinal anomalies associated with isolated congenital hemivertebra: the role of routine magnetic resonance imaging. J Bone Joint Surg Am. 2004;86(8):1704-1710. PMID: 15292418.
4. Aboughalia H, Noda S, Chapman T, Revzin MV, Deutsch GH, Browd SR, Katz DS, Moshiri M. Multimodality Imaging Evaluation of Fetal Spine Anomalies with Postnatal Correlation. RadioGraphics. 2021;41(7):2176-2192. doi:10.1148/rg.2021210066. PMID: 34723699.
5. Rong T, Jiao Y, Huang Y, Feng E, Sun H, Zhao J, Shen J. Morphological analysis of isolated hemivertebra: radiographic manifestations related to the severity of congenital scoliosis. BMC Musculoskelet Disord. 2024;25(1):112. doi:10.1186/s12891-024-07193-8. PMID: 38317143; PMCID: PMC10840169.
6. Solomon BD, Baker LA, Bear KA, et al. An approach to the identification of anomalies and etiologies in neonates with identified or suspected VACTERL (vertebral defects, anal atresia, tracheo-esophageal fistula with esophageal atresia, cardiac defects, renal and limb anomalies) association. J Pediatr. 2014;164(3):451-457.e1. doi:10.1016/j.jpeds.2013.10.086. PMID: 24332453; PMCID: PMC3943871.
7. Hemivertebra. Radiopaedia.org. https://radiopaedia.org/articles/hemivertebra. Accessed May 13, 2026.

Related Articles¶

• Butterfly Vertebra
• Block Vertebra
• Diastematomyelia