The
heterogeneity of KFS has made it difficult to outline the
diagnosis as well as the
prognosis for this disease.
Classification In 1912,
Maurice Klippel and Andre Feil independently provided the first descriptions of KFS. They described patients who had a short,
webbed neck; decreased range of motion (ROM) in the cervical spine; and a low hairline. Feil subsequently classified the syndrome into three categories: • Type I—Fusion of C2 and C3 with occipitalization of the
atlas. In 1953, further complications were later reported by Donald L. McRae;
flexion and
extension is concentrated within the C1 and C2 vertebrae. As with aging, the
odontoid process can become hypermobile, narrowing the space where the
spinal cord and
brain stem travel (
spinal stenosis). • Type II—Long fusion below C2 with an abnormal occipital-cervical junction. Similar to the C2-C3 fusion of McRae and could be viewed as a more elaborate variation.
Flexion, extension, and rotation are all concentrated in the area of an abnormal odontoid process or poorly developed ring of C1 which cannot withstand the effects of aging. • Type III—A single open interspace between two fused segments. Cervical spine motion is concentrated at single open articulation. This
hypermobility may lead to instability or degenerative
osteoarthritis. This pattern can be recognized as the cervical spine is often seen to be at an angle or hinge at this open segment. A classification scheme for KFS was proposed in 1919 by Andre Feil, which accounted for
cervical,
thoracic, and
lumbar spine
malformations. However, in 2006, Dino Samartzis and colleagues proposed three classification-types that specifically addressed the cervical spine anomalies and their associated cervical spine-related symptoms, with additional elaboration on various time-dependent factors regarding this syndrome. ==Treatment==