Klippel-Feil syndrome is a rare disorder that affects the skeletal system. The most distinguished characteristics are bones in the vertebrae (the spinal column), which are fused together abnormally. This is a congenital condition, which means that if affects people from birth.
What exactly is a Klippel-Feil syndrome?
Klippel-Feil syndrome is a rare congenital disorder that arises when the bones in the spinal column do not separate normally. The most common physical characteristics are a short neck, an abnormally low hair line and a limited range of movement in the upper back. Any of the cervical vertebrae may be implicated, but most commonly the disorder affects the discs C2-C3.
There are three variations of Klippel-Feil syndrome and they are classified according to the defective gene. The 3 types are as follows:
- KFS1: in this case, the syndrome is autosomal dominant and is linked to the defective GDF6 gene on the 8q22 chromosome
- KFS2: this type is autosomal recessive and relates to a mutated MEOX1 gene on the 17q21 chromosome
- KFS3: this form of the disorder is autosomal dominant and is associated with the defective GDF3 gene on chromosome 12p13
There are also different classifications for Klippel-Feil syndrome and these relate to the type of vertebral fusion:
Type 1- relates to fusion of the cervical bones (the vertebrae in the neck)
Type 2 - is linked to both cervical and thoracic vertebrae
Type 3 - involves cervical and mid-lower back vertebrae (thoracic and lumbar vertebrae)
Klippel-Feil syndrome is named after the doctors who first described the condition, Maurice Klippel and Andre Feil.
Causes of Klippel-Feil syndrome
In most cases, the cause is unknown due to sporadic mutation. However, there are cases linked to family history and both autosomal dominant and autosomal recessive inheritance patterns. In dominant case, there is a 50 percent chance of a parent passing a defective gene onto their offspring. In recessive cases, there is a 25 percent chance of two carrier parents having a child with Klippel-Feil syndrome and a 50 percent chance of the child being a carrier of the gene. The risk of inheriting the gene is the same for both males and females.
Who is affected?
Klippel-Feil syndrome affects both males and females, but females are most commonly diagnosed with the syndrome. This is a rare disorder and affects between 1 in 40,000 and 1 in 50,000 births. Most cases are classed as type 2 KFS.
How is Klippel-Feil syndrome diagnosed?
Klippel-Feil syndrome is often diagnosed at or shortly after birth based on symptoms and physical presentation. Often, imaging scans, such as an MRI (magnetic resonance imaging) are ordered to determine the type of fusion and the severity of the condition.
Symptoms of Klippel-Feil syndrome
The symptoms are varied and the syndrome tends to affect people in different ways, especially as there are different types and different patterns of inheritance. Some cases may be mild, while others may be much more serious and have life-limiting complications. Possible symptoms include:
- limited range of movement in the neck and upper back
- low hair line
- scoliosis (curvature of the spine)
- inability to carry out movements with one hand without repeating the same movement with the other hand (synkinesia)
- kidney problems
- lack of symmetry in the facial features
- impaired hearing
Other conditions can also be associated with Klippel-Feil syndrome, including an increased risk of heart problems, spina bifida, cleft palate and kidney disease.
Treating for Klippel-Feil syndrome
There are various treatments and therapies that can be used to manage symptoms and reduce the risk of complications. Treatment options include:
- Managing complications and abnormalities such as cleft palate, kidney disease and heart problems. This may involve medication and surgery
- Physiotherapy and occupational therapy
- Regular hearing checks and treatment where required, e.g. hearing aids
- Surgical treatment to treat abnormal fusion, stabilise the spinal column and treat chronic or severe pain
- Treatment for stenosis
- Genetic counselling
If there are treatment options available to you, they will be discussed in detail so that you understand what options are out there, how they could benefit you and what risks they carry.
What is the prognosis?
The prognosis varies according to the type of KFS and the severity of symptoms. Some people only have mild symptoms and they will be able to live a largely healthy life, while in other cases symptoms may be much more severe and this will have a major bearing on day to day life and sometimes life expectancy.