Klippel-Feil sequence: Short neck, low hairline at the nape of the neck and limited movement of the head. Klippel-Feil sequence is due to a defect in the early development of the spinal column in the neck, resulting in fusion of the cervical vertebrae. The condition is named for the French neurologists Maurice Klippel and Andre Feil who in 1912 reported "A case of absence of the cervical vertebrae with the thoracic cage going up to the base of the skull."
Klippel-Feil sequence is now the preferred name for the condition. It has gone by many other names including congenital brevicollis, congenital cervicothoracic vertebrae synostosis, congenital osseus-torticollis syndrome, congenital webbed neck syndrome, congenital synostosis of cervicothoracic vertebrae syndrome, congenital osseous-torticollis syndrome, dystrophia brevicollis congenita, Klippel-Feil anomalad, Klippel-Feil anomaly, Klippel-Feil deformity, Klippel-Feil phenotype, and Klippel-Feil syndrome.