Doctors at Duke Children's Hospital are treating the tight muscles caused by cerebral palsy with Botox injections. When given in combination with physical therapy, the shots help patients strengthen their weak muscles and restore normal movement.
The medication is injected into the muscles during an outpatient visit. Although anesthesia is not required for Botox injections, Duke pediatric neurologist Pedro Weisleder, M.D., Ph.D., teamed with Duke pediatric anesthesiologist Allison Ross, M.D., to develop a system for sedating children with inhaled anesthetics similar to the laughing gas used in many dental offices.
"Children don't take well to needles or painful procedures, and several parents asked if we could perform the injections under anesthesia to eliminate their child's pain," said Weisleder, an assistant professor of pediatric neurology at Duke University Medical Center. "The end result is that the procedure is painless and post-anesthesia recovery is rapid. It also allows me to give more accurate injections," he said. To identify the correct muscles for injection, Weisleder uses a special needle through which he can both electrically stimulate the muscles and deliver the medication.
The effects generally last about three months. During that time, patients work with a physical therapist to stretch and strengthen their weaker muscles. "Our goal is not to paralyze the muscles, it is to rebalance them around the joints," Weisleder said.
In cerebral palsy, the brain loses the ability to moderate the activity of contracting muscles. Muscles that produce contraction are stronger than those that produce extension, Weisleder said. Partially paralyzing the stronger muscles with botulinum toxin gives patients an opportunity to stretch and strengthen the weak muscles, he said. The long-term goal of the two components of the treatment – injections and physical therapy – is to achieve better muscle strength balance which may lead to restoring normal function, Weisleder said.
Cerebral palsy encompasses a group of physical and movement disorders that appear in the first few years of life. The muscle spasticity and tightness caused by the disorder make it difficult for people to perform fine motor tasks, such as writing, and causes problems with balance and walking. Though the disorder itself is not progressive, the consequences of the muscle spasms worsen over time, Weisleder said. Spasticity can interfere with daily activities and, in more severe cases, cause significant pain and snap joints out of alignment.
