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.
|Medical Terms||Other Names||
|80%-99% of people have these symptoms|
|Abnormal vertebral segmentation and fusion||0005640|
|Cervical C2/C3 vertebral fusion||0004602|
Asymmetry of face
Unsymmetrical face[ more ]
|Limited neck range of motion||0000466|
|Low posterior hairline||
Low hairline at back of neck
Decreased length of neck
|30%-79% of people have these symptoms|
|Abnormality of the ribs||
|Abnormality of the shoulder||0003043|
|Congenital muscular torticollis||0005988|
Hearing defect[ more ]
Abnormal curving of the spine
High shoulder blade
|5%-29% of people have these symptoms|
|Abnormality of limb bone morphology||
Abnormal shape of limb bone
Arm and/or leg bone differences
Limb abnormality[ more ]
|Abnormality of the cranial nerves||0001291|
|Abnormality of the sacrum||0005107|
Abnormality of cognition
Mental impairment[ more ]
Abnormal anus position
|Posterior fossa cyst||0007291|
Absent/underdeveloped kidney[ more ]
|Ventricular septal defect||0001629|
|1%-4% of people have these symptoms|
|Abnormality of cardiovascular system morphology||0030680|
Hand mirror movements
Mirror hand movements
Mirror movements[ more ]
|Mixed hearing impairment||
Hearing loss, mixed
Mixed hearing loss[ more ]
|Unilateral renal agenesis||
Absent kidney on one side
Missing one kidney
Single kidney[ more ]
|Percent of people who have these symptoms is not available through HPO|
|Abnormality of the pinna||
Abnormally shaped ears
Simple ears[ more ]
|Cleft upper lip||
|Conductive hearing impairment||
Conductive hearing loss[ more ]
|Fused cervical vertebrae||
|Sensorineural hearing impairment||0000407|
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.
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.
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.
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.
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. Submit a new question
My daughter was diagnosed with Chiari 1 malformation during childhood. Several years ago she was diagnosed with acute scoliosis and a fusion of 2 cervical vertebrae. Could it be possible that the Chiari is causing the scoliosis, even if there is no tethered cord or syringomyelia? Should she be checked for Klippel Feil syndrome? See answer
Is it possible for one identical twin to be born with Klippel Feil syndrome and not the other? See answer
Is there any relationship between Klippel Feil syndrome and low birth weight? See answer
As a young adult I was diagnosed with a fusion of C4 and C5. My question is whether this condition is automatically considered Klippel Feil Syndrome or whether there could be such a fusion without being diagnosed as KFS. See answer
Can Klippel Feil syndrome become life threatening? See answer
I am severely affected with Klippel Feil syndrome and my symptoms are worsening with time. Are there any research studies that I could participate in? I am also concerned about the risk to my future offspring. How can I learn more about this risk? See answer