These are the main movement disorders seen in children with cerebral palsy. Collectively they now represent 10 to 15% of children with CP, but there is a much higher proportion of adults with athetosis and choreoathetosis. The brain damage in older surviving adults was secondary to kernicterus, a disease now largely eliminated by treatment of Rh-negative mothers: one example of the preventive cure of many cases of CP. Unfortunately, high bilirubin levels in premature infants can still produce this type of damage.
What types of brain Injury or maldevelopment create these problems?
Athetosis and Choreoathetosis: Damage to the deep brain stem nuclei of the brain is caused by sudden total asphyxia. In the full term baby, this is most commonly caused by the placenta separating too soon in the birth process or an umbilical cord prolapses, effectively shutting off the supply of oxygen to the baby. Untreated, these delivery emergencies lead to a stillbirth. However, if the baby can be delivered fast enough, and resuscitated well, they may have damage just to the brain stem nuclei. If the delivery takes longer and the asphyxia more prolonged, the child may have HIE brain injury as well. This results in a mixed form of spastic quadriplegia with a movement disorder. This mixed form CP can also be seen in babies born prematurely.
Athetosis and choreoathetosis are more common in full-term babies.
Damage in this area of the brain leads to generalized difficulty with the control of movement and speech. The child with athetosis has large, slow, writhing whole limb or body movements while the movements of chorea are small rapid tremors. Speech impairments are more common in children with athetosis or the mixed pattern of choreoathetosis. Pure chorea is rare. Many physicians now lump all children with a movement disorder together under the generic term dyskinesia while others may use the term dystonia. Readers familiar to this blog will know my take on the use of generic terms. I do not think it is useful and further, I believe lack of precision in diagnosis leads to less specific treatment. In the dyskinesia group, athetosis and choreoathetosis are caused by damage in the brain stem nuclei and ataxia is caused by damage to the cerebellum.
Ataxia: This may be caused by maldevelopment of the cerebellum, or injury in the preterm or full term infant. With the addition of MRI scans and ultrasound techniques to visualize the cerebellum, more bleeds into this structure are now being diagnosed. I think of ataxia as a generalized problem with balance and coordination. It may exist as a pure form or in what is called mixed cerebral palsy. In the most severe forms of cerebellar damage, intelligence may be compromised.
What improvements are possible with repair, growth and maturation of the brain?
In the data from the best cerebral palsy registers, 23 to 24% of children with athetosis, choreoathetosis or ataxia score at a GMFCS Level of I to III. The rest are at level IV or V. In my long career, I have always been drawn to these children. In the majority, the cortex or thinking part of the brain is spared and their intelligence is unaffected. There are a few astounding people, like Christy Brown, author of My Left Foot, with severe mixed spastic/athetoid quadriplegia, who have demonstrated the hidden talent of people with these types of cerebral palsy. My interest in these problems is the challenge of seeing beyond the early habits formed in the first 4-6 years of life and recognizing that a much higher level of function is possible for the majority of children and a good number of adults as well. It is my belief that in most of these children, their therapy program is not effectively treating the effects of their specific brain injury.
The biggest problem is to sort out how to use the right thing, at the right time and in the right order. There is no magic cure and, as a group, these children are hard to treat. But parents are often driven to desperation by the hope of such a magic intervention. So they try one thing after another and nothing achieves their goals. I think there is a better way, if you are interested in adopting a more long-term plan of action. In my experience, in all with the will to improve, change is possible at any age. I recognize that this is a pretty challenging statement, but look at the 3 videos of children with Level IV to V athetosis in this post… Athetosis, Choreoathetosis & Ataxia – Treat the Common Problem
Muscle weakness in these children is caused by low tone (poor muscle activation) complicated by disuse muscle atrophy because they do not move well. Trunk support is needed and the change is rapid. Once the trunk is held in the correct position, their muscles can be effectively strengthened. The next big problem is poor body awareness (proprioception). Compressive garments support and also improve body awareness. The Wet Vest provides trunk support and allows the child to exercise out-of-gravity. For many, this is their first experience with moving freely. The folowing two posts demonstrate how much change is possible in adults with an integrated therapy program…
What is the risk of other sensory or brain problems?
The only common co-morbidity in children with athetosis and choreoathetosis is a higher incidence of hearing loss. They should all be screened with repeated screening as they mature and are able to participate in the examination. Children with ataxia may have a higher incidence of learning difficulties, but in prematurely born children with ataxia it is hard to separate any LD from the effect of prematurity.
These treatment tips are just the basic things that should be considered as a starting point. Try a supportive garment or go for a jog in a Wet Vest. These techniques should be more widely available and will only be made available when parents demand it. Parents need also to demand a specific brain diagnosis with an MRI. For brain lesion specific treatment, these children and adults should then be seen at a movement disorder clinic that is familiar with both pediatric and adult interventions. There are some very good interventions in the adult world, but you have to know both the location and severity of the brain lesion(s) as well as the condition of the rest of the brain. For example, I was recently told about an adult who had a MRI that showed a localized, specific lesion in the brain that would be treatable with a deep brain stimulator used for patients with Parkinson’s Disease. Because athetosis is a non-progressive, one time lesion, this patient would be expected to do better than most with progressive PD. The pace of discovery and change in all areas of neuroscience is astounding and I think experts in the adult movement disorder field should also assess these children as possible candidates.
As ever, I welcome your questions and comments.
The Full Series – Cerebral Palsy – GMFCS and Topography
Three R’s of Baby Brain Neuroplasticity
What Is Your Child’s Label?
Cerebral Palsy – The Best Possible Outcome and How To Get It
Cerebral Palsy – Diplegia – GMFCS I to III
Cerebral Palsy – Hemiplegia – GMFCS I to III – Part One
Cerebral Palsy – Hemiplegia – GMFCS I to III – Part Two
Cerebral Palsy – Spastic Quadriplegia – GMFCS Level I – III