Touching Lives - September 2003
Helping children with the world's deadliest toxin
Dr Peter Moore is Senior Lecturer and Consultant Neurologist at the Walton Centre for Neurology and Neurosurgery in Liverpool and has been using botulinum toxin to help children with cerebral palsy.
Yes, that’s botulinum toxin — the same stuff that people inject into their faces to reduce wrinkles! Although it is best known as a cosmetic treatment, botulinum toxin is used for all sorts of medical conditions. It is effective in relieving some kinds of pain, as well as easing different sorts of muscle spasms, and stopping excess sweating and salivation!
Supporting children with cerebral palsy
Up to 100,000 children in the UK have cerebral palsy, and Action Medical Research has a proud record of funding projects to help them. Cerebral palsy is neither an illness nor a disease but is a description of a physical impairment that affects movement.
It mostly occurs as a result of failure of part of the brain to develop either before birth or in early childhood. This can be due to a blocked blood vessel, complications in labour, extreme prematurity or illness after birth. Infections during pregnancy and early childhood can also cause cerebral palsy.
Children with cerebral palsy often have powerfully and uncontrollably overactive muscles. Dr Moore’s project helps such children by making their leg muscles become temporarily weaker and thinner when they are injected with the botulinum toxin. Having the treatment means the children experience less pain, discomfort and deformity, and they can control their muscles more easily.
Depending on the severity of their problems, the children received injections in up to five leg muscles. The large calf muscle was often treated, because when this muscle is stiff it forces the child to teeter on tiptoe. Other muscles commonly treated included the hamstrings, which can make the children walk with bent knees, and the inner thigh muscles that pull the knees together and make the feet cross over each other.
Earlier trials tested the effect of just a single set of botulinum injections, and results showed the therapeutic effect tended to wear off after three or four months. However, no one knew whether repeated sets of injections might give a longer lasting or even permanent benefit and it was not known if they were safe.
While undergoing the treatment some children were able to walk, or at least walk better. For others, physiotherapy was improved or they were able to manage without ankle splints. And simple everyday things like getting dressed were easier.
Dr Moore, who worked closely with Alder Hey Children’s Hospital in Liverpool, told Touching Lives: “We are really pleased with our results. No trial has looked so thoroughly at whether it was safe to treat children with botulinum toxin over long periods. It was very reassuring that we detected no long-term side effects after so many treatments, especially in such young children who are still growing, as safety is of paramount importance in any treatment.
“Now that we know that single sets of injections are helpful we are looking at our results to see if extra sets continue to help although any benefit derived is limited to the usual duration of the injection cycle. Our future work will aim to show the best ways to use the botulinum toxin and identify the children who will benefit most.
“We are thrilled with our findings but the results really belong to the children and parents who took part in the study. They were wonderful throughout and we are most grateful to them and to the paediatricians and orthopaedic surgeons in the North West who all supported us enthusiastically. We hope that many more children with cerebral palsy can benefit from this groundbreaking Action Medical Research project.”
How it works
Botulinum toxin works by stopping the nerve endings from sending chemical signals to the muscles to make them pull. Doctors select those muscles that are overactive, and carefully inject them with the toxin. It takes a week or two to start working, by temporarily poisoning the nerve endings within those muscles.
Botulinum is one of the world’s most powerful toxins, and these injections administer only a few millionths of a gram. At time of writing there is a limited service using botulinum toxin in some NHS centres in the UK. The Government has yet to decide whether, and by how much, to expand capacity, but it is hoped that the treatment will be made widely available in due course.