Last Updated on March 17, 2025
The Klippel Feil syndrome is a rare malformation in which there is a congenital fusion of two or more cervical and clinically characterized by shortening of the neck, neck stiffness, and low posterior hairline. Klippel Feil syndrome may also be accompanied by abnormalities of the genitourinary, cardiopulmonary, and nervous systems.
It is also called as congenital synostosis of the cervical vertebrae, or brevicollis.
It was first described by Klippel and Feil in 1912.
The condition is more common in females than
The reported incidence of Klippel Feil syndrome is reported between 0.2 to 0.7 per thousand and is observed to occur more in females.
Classification of Klippel Feil Syndrome
There are three morphologic groups of Klippel Feil Syndrome.
Type I
A massive fusion of the cervical spine [3 or more vertebrae]
Type II
A fusion of 1 or 2 vertebrae
Type III
– Thoracic and lumbar spine anomalies in association with type I or type II
Another classification by Samartzis and colleagues is used for evaluating the prognosis.
- Type I – a single-level fusion
- Type II – Multiple, noncontiguous fused segments
- Type III – Multiple, contiguous fused segments.
Associated Conditions
- Congenital scoliosis
- Sprengel’s deformity
- Kidney abnormalities
- Deafness
- Atlantoaxial instability
- Torticollis or tilted neck
- Webbed neck [Pterygium colli]
- Rib abnormalities
- Cervical ribs
- Congenital fusion of ribs
- Abnormalities of digits
- Syndactyly or joined digits
- Hypoplastic thumb
- Supernumerary digits
- Pectoralis major hypoplasia
- Hemiatrophy of upper or lower limbs
- Synkinesis (mirror motions)
- Degeneration of adjacent segments of the cervical spine due to increased stress
- Reproductive system abnormalities like ovarian agenesis and the absence of vagina
- Lung abnormalities
- Spinal cord compression
- Facial nerve palsy
Pathophysiology of Klippel Feil Syndrome
The cause of Klippel Feil syndrome is not established. The disorder results because there is a failure of normal segmentation of the mesodermal somites [blocks of cells during fetal development] during the third to the eighth weeks of fetal life. Genetic cause and fetal insult have been suggested as possible causes. It is not a familial disease though few genetic associations have been described.
Alteration in genes GDF6, GDF3 can be inherited in an autosomal dominant manner. When the disease is caused by the MEOX1 gene, it is inherited in an autosomal recessive manner.
Clinical Presentation
The patients who have upper cervical spine involvement [C1, C2] tend to present at an earlier than those with lower in the cervical spine.
[Know more about the upper and lower cervical spine.]
The syndrome can often be detected as an incidental finding.
Symptoms and signs vary according to the severity of the deformity.
A stiff neck is the most common presenting complaint. On examination following may be revealed
- Classical riad of following is seen in only half of the cases
- Posterior hairline is low
- Short webbed neck or pterygium colli [causes increase in neck width]
- Decreased range of cervical motion especially rotation
As noted before, all the signs are not seen in all the cases, only in about half.
Other associated features are
- Torticollis and facial asymmetry [Needs to be differentiated from congenital muscular torticollis ]
- Neurologic problems
- Cervical or cervicothoracic scoliosis
- Cervical spinal stenosis [Rare]
- Sprengel anomaly or congenital high scapula
Imaging
X-rays are basic investigations for the diagnosis of Klippel-Feil syndrome. AP and lateral views of the cervical spine are the standard views.
The x-ray may show
- Basilar invagination
- On lateral view
- Marked by elevation of dens elevation above McRae’s line
- McRae line connects the anterior and posterior margins of the foramen magnum
- Atlantoaxial instability is suggested by
- Atlanto-dens interval > 5 mm
- Cervical spinal canal stenosis [Spinal cord canal < 13 mm]
- Degenerative changes
- Calcifications of the intervertebral space
Image credit: Orthobullets
Flexion-extension radiographs are indicated if instability is suspected at the craniocervical junction or if 2 fused segments are separated by an open segment.
A chest x-ray is done for rib fusions.
CT scanning provides a better evaluation of spinal levels involved. It is especially useful for surgical planning.
evaluate the involved spinal levels better especially for surgical planning.
In patients with neurologic deficits, MRI is indicated. MRI would also be useful to reveal central nervous system anomalies, like syringomyelia.
Ultrasound of the abdomen is indicated to screen for finding kidney abnormalities.
ECG and echocardiography are done to rule out heart involvement.
The ears should be evaluated in all cases as the hearing loss is very common in Klippel Feil syndrome.
Treatment of Klippel Feil Syndrome
Klippel Feil syndrome has varied presentation and therefore multiple approaches of treatment depending on the individual involvement and presence of associated conditions.
Nonorthopedic therapy for Klippel Feil syndrome depends on the congenital anomalies present in the syndrome and treated accordingly.
The nonoperative treatment of orthopedic issues Nonoperative observation and is indicated in patients without symptoms with fusion of 1-2 disc spaces below C3. These patients are allowed to participate in contact sports.
The patients where the fusion involves C2 as well should not be allowed to play contact sports though.
Operative treatment consists of surgical decompression and fusion.
Basilar invagination, chronic pain myelopathy associated atlantoaxial instability, and adjacent level disease are common reasons for surgery.
The following points outline the specific nonoperative or operative procedures for specific problems
- Progressive cervical and cervicothoracic deformity
- Fusion
- Compensatory or associated congenital scoliosis
- Fusion
- Symptomatic cervical disc herniation
- Total disc arthroplasty or fusion
- Cervical spine instability
- Fusion
- Neurologic deficits and persistent pain
- Decompression and fusion
- Compensatory curve in the thoracic spine
- Bracing or fusion
- Symptomatic spinal stenosis
- Decompression
- Webbing of the skin
- Plastic surgery
- Contracture of the sternocleidomastoid muscle
- Division or partial excision
- Sprengel’s deformity
- Surgically restoration
