Klippel-Feil Syndrome

In 1912 Maurice Klippel and André Feil described a syndrome that is now called Klippel-Feil syndrome. It is caused by a failure in the normal segmentation of the cervical vertebrae during the early weeks of fetal development. Features include a short neck, restricted mobility of the upper spine and a low hairline. Any of the cervical vertebrae can be involved but the commonest fusion is of C2,3.

There are 3 types of cervical vertebral fusion:¹

• Type I is massive fusion of many cervical and upper thoracic vertebrae into bony blocks.
• Type II is fusion at only one or two interspaces although hemivertebrae, occipito-atlantal fusion and other anomalies might also occur.
• Type III is both cervical fusion and lower thoracic or lumbar fusion.

An alternative classification has ben proposed that is said to give a better reflection of prognosis:²

• Type I patients have a single congenitally fused cervical segment.
• Type II patients have multiple noncontiguous, congenitally fused segments.
• Type III patients have multiple contiguous, congenitally fused cervical segments.

In the review, 36% of patients had cervical spine-related symptoms and the majority had axial symptoms. Axial neck symptoms were highly associated with Type I patients, whereas predominant radicular and myelopathic symptoms occurred in Type II and Type III patients.

It is impossible to give figures for the incidence of the condition as it is highly variable in presentation and not all cases are recognised. The form of inheritance is also variable.

• Klippel-Feil syndrome is due to mutation on the long arm of chromosome 8 at 8q22.2 and is inherited as an autosomal dominant with limited penetrance³
• Klippel-Feil malformation is an autosomal recessive with mutation on 5q11.2.⁴

C5,6 fusion is more likely to be recessive.

Clinical presentation is varied because of the many associated syndromes and anomalies that can occur.⁵ It may occur with fetal alcohol syndrome⁶ and with vascular disruption. Associated abnormalities may include scoliosis, spina bifida, anomalies of the kidneys and the ribs, cleft palate, respiratory problems and heart malformations. There may also be abnormalities of the head and face, skeleton, genitals, muscles, brain and spinal cord, arms, legs and fingers.

• Presentation may occur at any time in life, often as an incidental finding.
• Upper cervical spine involvement tends to present at an earlier age than involvement of the lower cervical spine. Decreased range of movement of the neck is the most consistent finding with loss of rotation being more pronounced than is the loss of flexion and extension.
• A low hairline occurs in 40 to 50%.
• About 20% have neurological problems. These may be produced by hypermobility. Some patients present with pain. Scoliosis may be congenital or acquired and affects around 60%. Sometimes there is a compensatory scoliosis. High cervical abnormalities can cause acute spinal cord compression following comparatively minor trauma.
• Synkinesia is mirror movement of the upper extremity in which patients are unable to perform a movement of the right hand without performing the same movement of the left hand.⁷ This is disabling in everyday activities. It may be improved with therapy and usually improves with age.
• Many and varied abnormalities of the renal system have been reported in as many as a third of cases.
• Torticollis and facial asymmetry with possible craniofacial anomalies affect between a quarter and a half of all sufferers.
• The hearing loss can be sensorineural, conductive or mixed as there are many possible defects in the ear.⁸ One study found deafness in 35 of 44 or 80%.⁹
• Cardiovascular anomalies occur in 15 to 30% of cases. The commonest problem is ventricular septal defect.

The extent of investigation will depend upon the age of presentation, the nature of the problem and other confounding issues. It may be part of assessing the need for surgery to stabilise the neck. Such surgery carries risks and intubation for anaesthesia can be dangerous.

• Anteroposterior (AP) and lateral views of the cervical spine are basic. If abnormalities are present, carefully assessment of the atlano-occipital joint is required. Various other views may be required.
• CXR may show cardiac abnormalities or fusion of ribs.
• CT scan can be very useful at the base of the skull, especially if abnormalities are unilateral.
• MRI scan is useful to assess the spinal canal and any abnormalities of the spinal column such as syringomyelia.
• Ultrasound is used for imaging of the urinary tract. IVP may also be required.
• All children should have an assessment of hearing.
• If there are features of fetal alcohol syndrome but the mother is not known to be an alcohol abuser then tactful enquiry and investigation as outlined in articles on alcoholism, is required.

• Abnormalities of the heart or renal system may require surgical correction.
• Where hearing is impaired, appropriate intervention is required.
• Surgery is indicated in a number of situations. Fusion anomalies and the difference in growth potential between the two sides of the spine can make deformity progressive. Instability of the cervical spine requires fixation. Instability of the cervical spine can develop between two sets of fusion anomalies separated by a normal segment. Neurological deficits or persistent pain require surgery. Development of a compensatory curve in the thoracic spine may require surgical intervention or bracing. Symptomatic spinal stenosis may require decompression and fusion.
• Avoidance of trauma is important. A person with no neck may seem an ideal candidate for the front row of a scrum but this would be extremely dangerous.
• Genetic counselling may be required.

Maurice Klippel was a French neurologist and psychiatrist who was born in 1858 and died in 1942. He was a prolific writer, best known for his publications on neurology and psychiatry.¹⁰ André Feil was a French neurologist who was born in Paris in 1884.¹¹ They published together in 1912.¹²