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Klippel Feil syndrome

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Other Names:
Cervical vertebral fusion
Categories:
Klippel Feil syndrome (KFS) is a condition affecting the development of the bones in the spine. People with KFS are born with abnormal fusion of at least two spinal bones (vertebrae) in the neck. Common features may include a short neck, low hairline at the back of the head, and restricted movement of the upper spine. Some people with KFS have no symptoms. Others may have frequent headaches, back and neck pain, and other nerve issues.  People with KFS are at risk for severe spinal injury. KFS can occur along with other types of birth defects, and sometimes KFS occurs as a feature of another disorder or syndrome. The cause of most cases of KFS is unknown, but sometimes it is caused by genetic alterations (mutations) in one of several different genes. This condition is diagnosed based on a clinical examination, the symptoms, and imaging studies. Treatment is symptomatic and may include medications, surgery, and/or physical therapy.[1][2][3]
Last updated: 4/30/2020
The following list includes the most common signs and symptoms in people with Klippel-Feil syndrome (KFS). These features may be different from person to person. Some people may have more symptoms than others and symptoms can range from mild to severe. This list also does not include every symptom or feature that has been described in this condition.

Symptoms of KFS may include:[3][4]
  • Fusion of 2 or more spinal bones in the neck (cervical vertebrae).
  • Low hairline at the back of the head
  • Short neck
  • Limited neck range of motion
  • Scoliosis (curvature of the spine)
  • Sprengel deformity (abnormality of the shoulder blade)
  • Central nervous system abnormalities (including Chiari malformation, spina bifida, or syringomyelia), and/or neurological symptoms
  • Other skeletal abnormalities (including those of the ribs, limbs and/or fingers)
People with KFS may have headaches, muscle and nerve pain, or other neurological problems. There is an increased risk for narrowing of the spine (spinal stenosis) and serious spinal injury after mild trauma. Some people with KFS have few or no symptoms.[2][5]
Last updated: 4/30/2020

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

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Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Abnormal vertebral segmentation and fusion 0005640
Cervical C2/C3 vertebral fusion 0004602
Facial asymmetry
Unsymmetrical face
Crooked face
Asymmetry of face
[ more ] 		0000324
Limited neck range of motion 0000466
Low posterior hairline
Low hairline at back of neck
0002162
Short neck
Decreased length of neck
0000470
Webbed neck
Neck webbing
0000465
30%-79% of people have these symptoms
Abnormality of the ribs
Rib abnormalities
0000772
Abnormality of the shoulder 0003043
Congenital muscular torticollis 0005988
Hearing impairment
Deafness
Hearing defect
[ more ] 		0000365
Scoliosis 0002650
Sprengel anomaly
High shoulder blade
0000912
5%-29% of people have these symptoms
Abnormal cranial nerve morphology 0001291
Abnormal sacrum morphology 0005107
Abnormality of limb bone morphology
Abnormal shape of limb bone
Arm and/or leg bone differences
Limb abnormality
[ more ] 		0002813
Anal atresia
Absent anus
0002023
Cleft palate
Cleft roof of mouth
0000175
Cognitive impairment
Abnormality of cognition
Cognitive abnormality
Cognitive defects
Cognitive deficits
Intellectual impairment
Mental impairment
[ more ] 		0100543
Ectopic anus
Abnormal anus position
0004397
Hemiplegia/hemiparesis
Paralysis or weakness of one side of body
0004374
Posterior fossa cyst 0007291
Renal hypoplasia/aplasia
Absent/small kidney
Absent/underdeveloped kidney
[ more ] 		0008678
Spina bifida 0002414
Ventricular septal defect
Hole in heart wall separating two lower heart chambers
0001629
1%-4% of people have these symptoms
Abnormality of cardiovascular system morphology 0030680
Bimanual synkinesia
Hand mirror movements
Mirror hand movements
Mirror movements
[ more ] 		0001335
Mixed hearing impairment
Hearing loss, mixed
Mixed hearing loss
[ more ] 		0000410
Unilateral renal agenesis
Absent kidney on one side
Missing one kidney
Single kidney
[ more ] 		0000122
Percent of people who have these symptoms is not available through HPO
Abnormality of the pinna
Abnormally shaped ears
Auricular malformation
Deformed ears
Malformed ears
[ more ] 		0000377
Autosomal dominant inheritance 0000006
Autosomal recessive inheritance 0000007
Cervicomedullary schisis 0030325
Cleft upper lip
Harelip
0000204
Conductive hearing impairment
Conductive deafness
Conductive hearing loss
[ more ] 		0000405
Fused cervical vertebrae
Fused neck
0002949
Sensorineural hearing impairment 0000407
Variable expressivity 0003828
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Last updated: 7/1/2020
The exact underlying causes and mechanisms of Klippel Feil syndrome (KFS) are not well understood. Most cases of isolated KFS (meaning not associated with another syndrome) are sporadic, meaning there is no known family history or obvious genetic cause.[4] It is thought that KFS is likely caused by a combination of genetic and environmental factors.

In some people, genetic alterations (mutations) in at least three genes have been linked to KFS: GDF6, GDF3 and MEOX1.[1][4]
Last updated: 4/30/2020
In most cases, Klippel Feil syndrome (KFS) is not inherited in families and the cause is unknown. In some families, KFS is due to a genetic alteration in the GDF6, GDF3 or MEOX1 gene and can be inherited.[4] 

When KFS is caused by mutations in the GDF6 or GDF3 genes, it is inherited in an autosomal dominant manner.[1] All individuals inherit two copies of each gene.  Autosomal means the gene is found on one of the numbered chromosomes found in both sexes. Dominant means that only one altered copy of a gene is necessary to have the condition. The alteration can be inherited from either parent. Sometimes an autosomal dominant condition occurs because of a new genetic alteration (de novo) and there is no history of this condition in the family.

Each child of an individual with an autosomal dominant condition has a 50% or 1 in 2 chance of inheriting the alteration and the condition. Typically, children who inherit a dominant alteration will have the condition, but they may be more or less severely affected than their parent. Sometimes a person may have a gene alteration for an autosomal dominant condition and show no signs or symptoms of the condition.  

When KFS is caused by mutations in the MEOX1 gene, it is inherited in an autosomal recessive manner.[1] All individuals inherit two copies of each gene. Autosomal means the gene is found on one of the numbered chromosomes found in both sexes.  Recessive means that both copies of the responsible gene must be altered to have the condition.

People with autosomal recessive conditions inherit one alteration from each of their parents. The parents, who each have one gene alteration, are known as carriers. Carriers of an autosomal recessive condition typically do not have any signs or symptoms (they are unaffected). When two carriers of an autosomal recessive condition have children, there is a 25% (1 in 4) chance to have a child with the condition. 
Last updated: 4/30/2020
Klippel Feil syndrome (KFS) is typically diagnosed based on a clinical examination, symptoms and imaging studies (X-rays, MRI or CT scan). Additional studies may be necessary to look at other parts of the skeleton and other body systems. Some people with KFS have few or no symptoms, and are diagnosed by chance after having imaging studies for some other reason.[1][2]

Last updated: 4/30/2020

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.
Treatment for Klippel-Feil syndrome (KFS) is generally based on the symptoms. Management depends on the features and severity in each person, and may be lifelong. Some people with KFS require activity restriction, while others may require surgery. 

Some of specialists involved in the care of someone with KFS may include:[1][2][3]
  • Neurologist
  • Neurosurgeon
  • Orthopedic surgeon
  • Pain management specialist
  • Physical therapist
Last updated: 4/30/2020

Management Guidelines

  • Project OrphanAnesthesia is a project whose aim is to create peer-reviewed, readily accessible guidelines for patients with rare diseases and for the anesthesiologists caring for them. The project is a collaborative effort of the German Society of Anesthesiology and Intensive Care, Orphanet, the European Society of Pediatric Anesthesia, anesthetists and rare disease experts with the aim to contribute to patient safety.
Most estimates suggest that 1 in 40,000 to 1 in 42,000 people have Klippel Feil syndrome (KFS).[3][5] One study suggested a higher incidence of about 1 in 21,000 people[3] based on clinical examinations of people with and without symptoms. The exact incidence of KFS is unknown. 
Last updated: 4/30/2020

If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.

Healthcare Resources

Related diseases are conditions that have similar signs and symptoms. A health care provider may consider these conditions in the table below when making a diagnosis. Please note that the table may not include all the possible conditions related to this disease.

Conditions with similar signs and symptoms from Orphanet
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.
Visit the Orphanet disease page for more information.

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • The Centers for Mendelian Genomics program is working to discover the causes of rare genetic disorders. For more information about applying to the research study, please visit their website.

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

Social Networking Websites

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

In-Depth Information

  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
    Klippel Feil syndrome, Autosomal dominant
    Klippel Feil syndrome, Autosomal recessive
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Klippel Feil syndrome. Click on the link to view a sample search on this topic.

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know.

  1. Frikha R. Klippel-Feil syndrome: a review of the literature. Clin Dysmorphol. 2020; 29(1):35-37. https://pubmed.ncbi.nlm.nih.gov/31577545.
  2. Menger RP, Notarianni C. Klippel Feil Syndrome. In: StatPearls. Treasure Island (FL): StatPearls Publishing. 2020; https://pubmed.ncbi.nlm.nih.gov/29630209.
  3. Zhou PL, Poorman GW, Wang C, Pierce KE, Bortz CA et al.. Klippel-Feil: A constellation of diagnoses, a contemporary presentation, and recent national trends.. J Craniovertebr Junction Spine. 2019; 10(3):133-138. https://pubmed.ncbi.nlm.nih.gov/31772424.
  4. Klippel-Feil Syndrome. National Organization for Rare Disorders (NORD). Updated 2019; http://rarediseases.org/rare-diseases/klippel-feil-syndrome/.
  5. Gruber J, Saleh A, Bakhsh W, Rubery PT, Mesfin A. The Prevalence of Klippel-Feil Syndrome: A Computed Tomography-Based Analysis of 2,917 Patients. Spine Deform. 2018; 6(4):448-453. https://pubmed.ncbi.nlm.nih.gov/29886918.