Health A to Z

Neurological Conditions

Athetosis - Overview

A child may have spastic cerebral palsy in his or her legs as well as a degree of athetosis elsewhere. The characteristics of each of these syndromes are not mutually exclusive. With athetosis, the muscles are subjected to excessive and uncontrollable movement. These movements also increase with a child’s excitement and in response to surrounding environmental stimulation. Likewise, the more relaxed a child is, the less often these abnormal movements occur. When a child is sleeping, the movements stop altogether.


The movements of a stimulated child form what is called an extensor thrust. When this happens, the arms rapidly extend outward and back, the palms turn toward the floor, the fingers spread and overextend, the knees come together, and the feet turn inward with the toes up. The child’s neck flexes, pulling the head back and to the side, and the mouth opens with the tongue sticking out. These movements can present extreme difficulty for a child when eating and drinking. The child may also have shallow and irregular respiration, which affects oxygen flow to the brain and increases the chance for respiratory infections. Patients with athetotic cerebral palsy also have difficulty with balance and walking.


Some of the known causes or contributors to cerebral palsy include:


  • 1) An infection, such as rubella (German measles) or toxoplasmosis (a tissue infection), during pregnancy
  • 2) Jaundice in the baby's brain after birth
  • 3) A viral infection that affects the brain
  • 4) Hydrocephalus
  • 5) Meningitis of the membranes surrounding the brain and spinal cord
  • 6) A severe head injury in the baby
  • 7) Severe convulsions in the baby
  • 8) Drugs and/or alcohol abuse during pregnancy
  • 9) Blood type differences between mother and fetus
  • 10) Anemia (has too few red blood cells) during pregnancy
  • 11) Premature birth with internal bleeding in the baby's head
  • 12) Lack of oxygen to the baby during development or delivery
  • 13) Early separation of the placenta or damage to the umbilical cord

While some of the causes of cerebral palsy are still unknown, there are many known factors that can cause or contribute to brain damage before or after birth. Preventive methods, such as proper prenatal care, can eliminate some causes, while others are as yet unpreventable.

Cerebral Palsy - Overview

Cerebral palsy is an umbrella term for describing a group of persistent disorders that damage a person’s ability to control body movement and posture. These disorders result from injury to the motor areas of the brain. Cerebral palsy affects two to six infants out of every 1,000 births, and is the most common disability among children in the U.S. The problem causing cerebral palsy may occur while the infant is still in the womb or after birth, and the problem is not always detectable during a child’s first year of life.


Cerebral palsy may affect one arm or leg, an arm and leg on the same side, only the legs, all four limbs, or any combination of arms and legs. Whatever the affected areas may be, the muscle types involved are often the same. Muscles that enable people to bend their arms and legs are called flexor muscles. Extensors muscles are the opposite of flexors and enable a person to straighten these limbs back out. It is the inability to control these and other muscles that defines the most common cerebral palsy syndromes


Patients with cerebral palsy can have a range of symptoms. These symptoms usually do not worsen over time and include:


  • 1) Difficulty with fine motor skills
  • 2)_ Instinctive muscle movements
  • 3) Difficulty maintaining balance and walking
  • 4) Learning problems
  • 5) Vision defects
  • 6) Speech difficulty
  • 7) Sucking and swallowing problems

Spastic cerebral palsy is the most common form and is the type seen in close 80 percent of cases. Patients with this form are unable to relax their muscles, which respond by contracting further if the patient or someone else tries to stretch them. This spasticity affects the function of individual muscles, especially flexor muscles.

When spasticity occurs in the arms, the flexors tighten, pulling the elbows toward the body, and hands and wrists toward the chin. The hands themselves form tight fists. This constant tightened state may in turn weaken the extensor muscles, stretching them to the point where some of their functionality is lost. When spasticity occurs in the legs, the flexor muscles in the calves are affected. When this happens, the heels become raised, pushing the toes downward and often causing a child to walk on their toes.

Spasticity in the legs also affects the adductor muscles (the inner thigh muscles). Adductor muscles pull a body part toward its midline, such as those that pull the arms to a person’s side or close a person’s legs. In patients with cerebral palsy, the inward pull of the adductor muscles is so strong that the legs cross over each other or scissor. This motion also rotates the legs inward at the hips, pulling them away from the hip sockets, which can lead to abnormal socket development and hip dislocation.

Other conditions associated with spastic cerebral palsy may include an overstated response to startle stimulation, a degree of mental impairment, and weak respiration. Some children with spastic cerebral palsy develop a curvature of the spine. This results from remaining in a constant upright position, which prevents the trunk muscles needed for supporting the spine from developing properly.

Children with mild cerebral palsy may only have a minor limp or an awkward walk, while patients with severe cases will require care and supervision throughout their lives. Many of the infants born with cerebral palsy also experience some degree of mental retardation and/or have seizures.

Diagnosis & Treatment

Cerebral palsy may be difficult to diagnose in a child’s first year of life. Because much of the development in this first year is based on motor functions, observation of these developing functions is often needed to make an accurate diagnosis. Actions such as reaching for toys, rolling over, sitting, standing, and walking develop during this time, and a delay in this development will prompt a physician to look for other physical symptoms if cerebral palsy is suspected. These signs may include abnormalities in muscle tone, movements, and reflexes. A doctor may also look at an infant’s hand preference. During their first year, babies normally do not show hand preference. But infants with cerebral palsy in only one side of the body may develop a hand preference early on, using their unaffected side to reach and grab for toys even if they are closer to their opposite, affected hand.


Once cerebral palsy has been diagnosed, predicting how or when a child will develop their motor milestones is often intricate. It is known that once an activity has been learned, it does not regress. For example, walking can be a very difficult and complex task for children with cerebral palsy. Once the child has learned to walk, they will always be able to walk unless something other than cerebral palsy affects the child. If this sort of degeneration should occur, it is important for parents to call the doctor immediately.


While physical observation of motor functions is the best method for diagnosing cerebral palsy, a physician may order other tests to rule out other neurological disorders. For example, computed tomography (CT) scans, magnetic resonance imaging (MRI), and head ultrasounds all take images of the brain and surrounding areas and may be useful in detecting serious conditions such as hydrocephalus (abnormal accumulation of fluid in the brain). While these tests are not used to confirm or rule out cerebral palsy, these scans may reveal the presence of brain cysts, scars, or other abnormalities that may have caused the cerebral palsy.


Although cerebral palsy cannot be cured, in many instances it can be effectively treated and managed. Treatment often involves a combination of approaches and varies with each individual. Physical therapy can teach patients how to train and exercise their muscles, speech therapy can help improve speaking and other tasks involving the mouth, and eye surgery or prescription lenses can repair or compensate for vision problems. Some patients benefit from antispasticity medicines, while others require orthopedic surgery or neurosurgery to change the position of an arm or leg, so assistance devices such as crutches or braces can be used. Newer techniques include Botox injections directly into involved muscles to decrease muscle rigidity and Baclofen infusion pumps that provide a constant stream of muscle relaxant into the spinal fluid.


Many people with cerebral palsy live productive and relatively normal lives. In fact, in the last 40 years, the number of people with cerebral palsy who are active in the workforce has almost doubled. Like many other conditions, education about cerebral palsy and local support groups can be the greatest tools for managing the disorder and preventing complications.