What is athetoid cerebral palsy?
Athetoid cerebral palsy (also known as "dyskinetic cerebral palsy") is a movement disorder caused by damage to the developing brain.
This type of cerebral palsy is characterized by abnormal, involuntary movement.
Children with athetoid CP fluctuate between hypertonia and hypotonia. Hypertonia is used to describe unusually high muscle tone, which creates stiffness and tension in the muscles. Hypotonia is used to describe unusually low muscle tone, which causes “floppiness” in the muscles. This inability to regulate muscle tone is what causes CP symptoms.
Athetoid CP can also result in issues surrounding voluntary movement in the hands, arms, feet and legs — making it hard to walk or grasp objects. Treatment for this type of cerebral palsy is centered on various therapies, medications and surgeries that can help to manage symptoms and prevent any future complications.
Types of athetoid CP
Athetoid cerebral palsy may be given other distinctions to further classify the condition based on the specific type of involuntary movement.
The various types of athetoid CP include:
- Dystonia - Slow, rotational movement of the torso, arm or leg.
- Chorea - Sudden involuntary movements, especially in fingers and toes.
- Athetosis - Sluggish, writhing movements, mainly in fingers and face.
- Choreoathetoid - A combination of chorea and athetosis.
- Ataxia - Loss of balance and coordination.
- Rigidity - High muscle tone due to hypertonia causes restricted movement.
- Dyskinesia - General term to describe involuntary movements. Athetoid CP is often interchangeably referred to as dyskinetic CP for this reason.
Causes and risk factors
Athetoid cerebral palsy is one of several types of movement disorders caused by a brain injury. Each type of cerebral palsy differs based on which part of the brain is damaged.
Athetoid cerebral palsy is caused by damage to the basal ganglia and/or the cerebellum.
Basal ganglia damage
The basal ganglia are a group of nuclei in the brain responsible for coordinating voluntary movement. The basal ganglia are located within the cerebral cortex, a part of the brain that helps control motor function. The basal ganglia also help regulate thinking and learning. Damage to the basal ganglia affects motor function development and causes involuntary movements.
The cerebellum is responsible for regulating coordination and precision of movements — both of which are essential to fine motor skills and balance. When the cerebellum is damaged, balance and coordination become more challenging. The cerebellum is also an important part of cognitive functions, such as communication and attention. A damaged cerebellum can cause co-occurring disorders, such as autism or epilepsy.
Damage to the cerebellum and/or basal ganglia can be caused by:
- Infections, such as meningitis
- Trauma to the developing brain
- Lack of oxygen to the developing brain
Certain risk factors increase the chances of brain injuries that cause athetoid cerebral palsy. In general, the risk factors for all types of CP are the same, including: premature birth, severe infantile jaundice and blood clotting in the placenta.
Symptoms of athetoid cerebral palsy
The signs and symptoms of athetoid CP vary based on the severity of the condition and location of movement issues. The symptoms of athetoid cerebral palsy are a result of problems with both high and low muscle tone, which can vary on a daily basis. High muscle tone causes stiffness and jerky movement. Low muscle tone causes floppiness in the muscles, characterized by issues such as trouble sitting up.
The most common symptoms associated with athetoid CP are:
- Involuntary movement
- Poor posture
- Twisting of the torso
- Slow, writhing movements
- Abrupt movements
- Grimacing or drooling
The symptoms of athetoid CP depend on whether the damage was solely to the basal ganglia, or if both the cerebellum and basal ganglia were damaged. If both areas are damaged, this will likely cause problems with balance and coordination.
Parents and caregivers usually begin noticing signs of involuntary or jerky movements when their child is around 9 months or older. In many young children, irregular movement may be indicative of a developmental delay, but not necessarily a sign of cerebral palsy.
Athetoid cerebral palsy may be present in a child who:
- Doesn’t kick legs
- Seems stiff or rigid
- Seems limp
- Doesn’t hold up head at three months old
- Doesn’t reach for objects
- Doesn’t smile by three months old
- Doesn’t roll over
Treatment for athetoid CP
Treatment for cerebral palsy helps children with this disorder become more independent and confident in their abilities. Treatment methods such as physical therapy and speech therapy help improve existing symptoms, while also preventing any future complications later in life.
Physical therapy typically incorporates a series of strength training exercises, resistance bands and machines to help improve low muscle tone. Physical therapists work with children and adults with CP to overcome any sensory impairments, such as touch and depth perception, that make movement more difficult.
Therapy for this type of CP is typically based on improving overall mobility. This includes exercising the face and tongue muscles, as grimacing and drooling is common in children with this type of CP. Athetoid CP can also cause difficulties holding posture or keeping the body in a steady, upright position. Physical therapists will use various exercises to increase the strength in these muscles and prevent any further complications.
Occupational therapy is used to enhance a child's ability to independently play and learn. An occupational therapist will help to make everyday tasks, such as grasping objects, writing or using assistive mobility devices, easier on a child with this type of CP.
Specific exercises used in occupational therapy for athetoid CP include stretching with weights and resistive equipment, as well as incorporating functional and playful activities to keep children interested. Occupational therapy will allow children to form relationships and respond to the demands of daily life with increased mobility and confidence.
For those diagnosed with CP, speaking, eating or breathing can be a challenge. Speech therapy is used to alleviate these problems, as well as increasing language and vocabulary development, articulation and breathing control.
After working with a speech therapist for a series of sessions, people with CP often begin to have more control over their face and tongue muscles. Speech therapy can also make daily tasks easier on a child with athetoid CP, allowing for increased independence.
Most of the medications prescribed for athetoid cerebral palsy are used to treat secondary conditions that result from developmental brain damage. For example, anticonvulsants are used to reduce seizures and over-the-counter acid reflux medications, such as Zantac, are prescribed for children with weak gastroesophageal muscles.
Ritalin and other medications treat attention deficit hyperactivity disorder (ADHD), which is diagnosed in up to 20 percent of children with CP. Medications to control drooling and incontinence are also useful for those with athetoid cerebral palsy.
Surgery for children with cerebral palsy is used to correct and prevent issues with the joints, muscles and tendons by correctly aligning parts of the body to foster healthy growth. Although it is not common in athetoid CP, surgery can be used to correct joint deformities and dislocations due to high muscle tone.
Embracing a life with CP
While a cerebral palsy diagnosis may come as a surprise to many families, this is a condition that can be managed effectively through proper treatment and continued care. There are bound to be some challenges along the way, however, maintaining a positive outlook can allow children and adults to embrace life with CP.
To learn more about athetoid cerebral palsy, try downloading our free Cerebral Palsy Guide. This guide includes 12 pages of in-depth information for families affected by cerebral palsy.