Klippel-Feil syndrome

Congenital abnormality of spine with failure of normal segmentation, resulting in mass of spine with no recognizable vertebrae; may affect any vertebra, although most common in cervical spine. Condition can range from lethal to asymptomatic and is associated with short neck, low posterior hairline, reduced lateral range of motion of neck, scoliosis (50%), hearing deficits (30%), renal abnormalities, and congenital heart defects. In children, bimanual synkinesias (mirror movements) may occur.