Pseudo temporomandibular joint ankylosis in a patient with Klippel-Feil syndrome

Abstract

Klippel-Feil syndrome (KFS) is a rare congenital abnormality characterized by shortening of the neck because of fusion of 2 or more cervical vertebrae frequently associated with other congenital abnormalities of the spine with or without neurologic disturbances. In its extreme form, there is a gross restriction of movement of the neck. A slight abnormality may go unrecognized until chance detection (usually in an x-ray of the cervical spine). Maurice Klippel, a French internist, and Andre Feil first recorded the complete picture of the syndrome in a case report of a 46-year-old tailor having an unusually short neck with gross restriction of movement. He had only 4 cervical vertebrae, which were fused in a single mass with posterior spina bifida. The syndrome consists of easily recognizable signs (short neck and posterior hairline lower than normal) and definite limitation of head and neck movements. It may also be associated with anomalies of the genitourinary, musculoskeletal, neurologic, and cardiac systems. However, a patient of this syndrome may otherwise be normal. Three patterns of vertebral abnormalities have been described with KFS: type I: fusion of several cervical and upper thoracic vertebrae. Type II: fusion of 1 or 2 interspaces sometimes accompanied by hemi-vertebrae, occipito-atlantal fusion, and other vertebral abnormalities. Type II has the lowest risk of the scoliosis. Type III: fusion of cervical vertebrae associated with fusion of lower thoracic and lumbar vertebrae. A fourth type (type IV) has been suggested and is associated with sacral agenesis. Abnormal bony masses have been reported in the mandibular ramus region along with congenital duplication of mandibular rami. These masses extend from the zygomatic arch region toward the ascending ramus of the mandible and the maxillary tuberosity area (producing partial to complete trismus). The inferior end either lies free in the buccal soft tissues or may be attached to the rudimentary coronoid process by a fibrous joint.