Klippel-Feil syndrome associated with congenital cervical dislocation: report of an autopsy case.

Klippel-Feil syndrome is an uncommon congenital anomaly that is characterized by abnormal fusion of the cervical vertebrae and occasionally accompanied by various anomalies of other bones and internal organs. We report the autopsy case of a 5-year-old girl with this syndrome ssociated with congenital cervical dislocation, with special reference to the pathological findings of the vertebral column and spinal cord. Principal anomalies of the cranio-spinal axis were as follows: partial defect of the clivus, scoliosis, hypoplasia of the whole cervical vertebrae, anterior dislocation of C7 with S-shaped deformity of the spinal canal, fusion of the spinous processes of the cervical and thoracic vertebrae, fusion of the vertebral bodies of C6 and C7 with collapse of C7, and spina bifida occulta of L5 and S1. In addition to these skeletal anomalies, subarachnoid vascular malformation in the medulla oblongata, a bronchogenic cyst in the posterior mediastinum, anomalous lobation of the lungs, and the mobile cecum were found at autopsy. The cervical cord showed an increase of the antero-posterior diameter, multifocal spongy changes of the white matter, and partial branching or duplication of the central canal. The brain showed features of anoxic encephalopathy. The partial defect of the clivus, C7 dislocation, and various lesions of the medulla oblongata and cervical cord were interpreted as integral components of, or lesions closely associated with, Klippel-Feil syndrome.