What are the main symptoms of Klippel-Feil syndrome?
Specific health problems present in Klippel-Feil Syndrome (KFS) often are different from one individual to another and all of the symptoms may not occur in one person. However, all forms of KFS share the main feature which is fusion of at least two of the seven neck bones in the spine (cervical vertebral fusion) that happens before birth. In the most recent classification system by Clarke, individuals with KFS are divided into groups based on the way the condition runs in the family (or not), the lowest level of cervical vertebrae that are fused, and health issues seen in addition of the fused cervical vertebrae.
Class 1 KFS is defined as individuals with fusion at the highest of the C1-2 cervical vertebrae, a very short neck, and recessive inheritance of KFS through the family.
Class 2 KFS is defined as having the highest level of fusion of the C2-3 cervical vertebrae and an autosomal dominant pattern of inheritance of KFS through the family.
Class 3 KFS, has fusion between any of the cervical vertebrae except C1-2, no other medical issues related to KFS, and finding of recessive inheritance of KFS through the family.
Class 4 KFS includes mainly females who have fusion of any cervical vertebrae, Duane syndrome (unusual eye (ocular) movements including limited or absent horizontal eye movements, retraction or "moving back" of the eyeball into the eye cavity (orbit) upon attempting to look inward, and, in some cases, crossed eyes), and/or hearing impairment that is present at birth.
Overall, signs and symptoms of any class of KFS may include:
- fusion of at least two of the seven neck bones in the spine (cervical vertebral fusion)
- very short neck
- low hairline at the nape of the neck
- chronic head pain and headaches
- kidney malformations
- heart malformations
- webbing between some fingers and toes
- missing or fused ribs including cervical ribs
- unusually formed bones in the head, neck,face, and joints and limbs including arms, hands, legs, knees, hips, feet.
- cleft palate
- underdeveloped shoulder blades
- one shoulder blade higher than the other (Sprengel's deformity)
- scoliosis (abnormal spinal curvature sideways)
- kyphosis (abnormal spinal curvature of the back)
- inability of the spinal column (vertebrae) to maintain its standard shape and function during daily activities (vertebral instability) leading to other symptoms such as chronic head and back pain, unusual load and stress on the spine and parts of the body compensating for the weight, and/or nerve compression.
- chronic musculoskeletal pain related to nerves, bones, joints, muscles.
- torticollis (tightened neck muscles on one side that leads the neck to twist to one side, causing the head to tilt.
- cervical dystonia (painful condition in which your neck muscles contract involuntarily, causing the head to twist or turn to one side.)
- generalized dystonia (involuntary muscle contractions that are not limited to a single muscle group or half the body, but may affect all four limbs, as well as the face, neck and spine. However, certain areas may be spared.)
- laryngeal dystonia (a chronic voice disorder characterized by momentary periods of uncontrolled spasms of the muscles of the voice box (larynx).
- hearing loss
- limited neck range of motion
- incomplete closure of some vertebrae (spina bifida occulta) with or without Tethered Cord Syndrome (a neurological disorder caused by tissue attachments that limit the movement of the spinal cord within the spinal column. )
- leg weakness
- unusual formation of internal female reproductive organs in girls such as Müllerian agenesis (also known as Mayer-Rokitansky-Küster-Hauser syndrome) or duplicate reproductive organs (uterus).
- inability to control urination (urinary incontinence)
- underdeveloped vertebrae (hemivertebrae)
- limited or absent horizontal eye movements,
- retraction or "moving back" of the eyeball into the eye cavity (orbit) upon attempting to look inward
- misalignment of the eyes or "crossed eyes" (strabismus)
- Duane syndrome (an eye movement disorder present at birth characterized by horizontal eye movement limitation [a limited ability to move the eye inward toward the nose , outward toward the ear, or in both directions)
- facial asymmetry
- mirror movements (a disorder of motor control in which purposeful movements started in one arm or leg are copied by the other)
- internal organs such as the heart located on the other side of the body (Situs inversus)
- an intentation or dip in the middle of the chest (pectus excavatum)
- syringomelia (the development of one or more fluid-filled cysts in the spinal cord)
SOURCE: Emory University - Department of Human Genetics in collaboration with ThinkGenetic • https://www.thinkgenetic.com/diseases/klippel-feil-syndrome-109938/symptoms/66925 • DATE UPDATED: 2019-07-26
Klippel-Feil Syndrome, NORD, https://rarediseases.org/rare-diseases/klippel-feil-syndrome/
"Isolated Klippel-Feil syndrome" Orphanet, https://www.orpha.net/consor/cg,i-bin/OC_Exp.php?Lng=GB&Expert=2345
"Wildervanck syndrome", NORD, https://rarediseases.org/rare-diseases/wildervanck-syndrome/
Klippel-Feil syndrome 1, autosomal dominant; KFS1, OMIM, https://omim.org/clinicalSynopsis/11810