Isolated Klippel-Feil Syndrome

Klippel-Feil Syndrome is characterised by improper segmentation of cervical segments resulting in congenitally fused cervical vertebrae.

Epidemiology

The prevalence has been estimated at 1 in 50,000.

Clinical description

The syndrome was first reported in 1912 by Maurice Klippel and André Feil and is often associated with the classic clinical triad of manifestations consisting of a low posterior hairline, short neck, and limited neck range of motion. However, subsequent studies have shown that only 34% to 74% of patients present with such findings. The phenotypic expression of Klippel-Feil syndrome is variable, occurring with or without extraskeletal manifestations or any additional spinal abnormalities.

Etiology

The syndrome is caused by failure of cervical segmentation in the early stages of pregnancy but the exact aetiology and mode of inheritance remain unknown.

Diagnostic methods

Lateral neutral and flexion-extension as well as anteroposterior plain cervical radiographs demonstrating congenitally fused vertebrae are diagnostic. Magnetic resonance imaging and computed tomography can assist in the diagnosis and be used to evaluate for associated abnormalities.

Differential diagnosis

Differential diagnosis should include a surgical history of spinal fusion, ankylosing spondylitis, juvenile rheumatoid arthritis, fibrodysplasia ossificans progressiva (see these terms), and active or "burned out'' osteomyelitis.

Management and treatment

Treatment is based on the management of commonly associated symptoms, which include neck pain, radiculopathy, and/or myelopathy. The mainstay of treatment for patients with predominantly neck pain is conservative, non-operative measures. Radiculopathy secondary to nerve root impingement is also managed initially with conservative interventions and in selected cases may include spinal injections. Myelopathy due to spinal cord compression is typically attributed to congenital cervical stenosis, but may be exacerbated secondary to spinal cord compression from a combination of vertebral osteophyte and/or soft tissue compression. Patients with extensive congenital cervical fusion and/or excessive motion at a non-fused motion segment are regarded as being at high-risk for spinal cord injury and should alter daily activities to limit such potential injury. Surgical intervention may be warranted for specific cases where excessive cervical or craniovertebral motion is deemed potentially unstable and is associated with an increased risk of spinal cord injury.

Prognosis

The prognosis is variable.