Congenital scoliosis is scoliosis that occurs in children whose vertebrae are abnormally formed during their development in the womb. This abnormality develops in the fetus at 4 to 6 weeks of gestation. Congenital scoliosis is related to hemivertebra, a rare congenital spinal deformity where a section of a vertebra fails to develop, typically resulting in a wedge shape.
The exact cause of congenital scoliosis is unknown, but given that the condition runs in families, the cause is most likely genetic. Congenital scoliosis is related to the following congenital spinal anomalies:
Combination of Bars and Hemivertebra
- In some cases, a spine may develop with an unsegmented bar on one side and a hemivertebra on the other, resulting in an increased curvature of the spine.
- A spine with a scoliosis curve will sometimes develop other curves in the opposite direction above or below the affected area to compensate for and balance out the scoliosis curve.
Failure of Separation of Vertebrae
- During development, the spine initially forms as a single tissue which later divides into segments that develop into the vertebrae. If the segments fail to separate it results in partial or complete fusion of two or more vertebrae. The unsegmented bar prevents the spine from growing straight and results in a spinal curve.
- A section of a vertebra fails to develop, typically resulting in a wedge shape. The wedge-shaped hemivertebra creates a sharp angle in the spine which causes the spine to curve as the child grows.
- Disorders that affect the nerves and muscles (e.g. cerebral palsy, muscular dystrophy, spina bifida, etc.) and cause muscle weakness, poor muscle control, or paralysis can result in or occur in association with scoliosis.