Departments of Neurology and Neurosurgery
Spasticity - Intrathecal Baclofen Pump Therapy
What is Spasticity?
Spasticity is a chronic neurological disorder characterized by muscle stiffness. Spasticity causes muscle tone to become exaggerated, which makes the normal stretching and flexing of everyday movement impossible.
Spasticity can be an extremely debilitating disorder because spastic muscles can become so tight and contracted that it becomes difficult to move them. Spasticity can interfere with walking, speaking clearly or clenching your fists.
Spasticity usually occurs when the part of the nervous system that controls voluntary movement becomes damaged. When this happens, the brain can send false signals to the muscles, which then tense up when they should relax.
Numerous disorders and injuries can bring on spasticity. These include cerebral palsy, stroke, traumatic brain injury, infection, multiple sclerosis, spinal cord injury and metabolic diseases such as phenylketonuria and adrenoleukodystrophy.
How is Spasticity Treated?
Most spasticity improves with regular stretching of the affected muscles. Range-of-motion exercises, if begun in the early stages, can prevent permanent shortening and shrinkage of the muscles.
Stretching alone doesn't work for all patients, however, and some must take muscle-relaxing medications such as baclofen, diazepam or clonazapem. In some severe cases, surgery may be necessary.
What is Baclofen Pump Therapy?
For patients who don't respond well to oral spasticity drugs, there is intrathecal baclofen therapy, known as ITB. This involves the injection of the muscle-relaxing drug baclofen into the intrathecal space that surrounds the spinal cord.
Baclofen is delivered through a pump, which is surgically implanted into the abdomen of the patient. The baclofen is pumped directly into the surrounding spinal cord fluid.
When the medicine in the pump runs low -- as it will every couple of months -- the machine beeps and can be refilled easily by injection. The pump itself generally lasts about four years before it has to be replaced.
What are the benefits of Baclofen Pump Therapy?
The direct delivery method of ITB therapy is very effective. Since baclofen doesn't have to circulate throughout the body to get to the spinal cord, smaller amounts of the drug are needed. This reduces side effects such as drowsiness. It also ensures that more of the drug actually reaches the affected nerve cells.
What are the Risks of Baclofen Pump Therapy?
As with all surgery, there is a possibility of an adverse reaction to the anesthesia. There is also a risk of infection or bleeding. In some cases, bowel function, bladder control or sexual function can be impaired.
Patients may experience insomnia, double vision, diarrhea, vomiting, weakness, constipation, seizures, nausea, dry mouth, dizziness, difficulty breathing, coma or drowsiness if the pump malfunctions and delivers too much medication at once.
Patients should go to the emergency department immediately in such an instance, where doctors can administer medication to counter the effects of the baclofen.
Who are Good Candidates for Baclofen Pump Therapy?
The baclofen pump is used to treat severe spasticity. It is particularly useful in treating cerebral palsy patients, who have spasticity of the lower limbs. Patients who have extremely painful muscle spasms, which affect the arms or legs or both, are usually considered for the pump.
The pump is rarely implanted in children under the age of 4, since small children lack the body mass to support a pump. Before implanting the pump in anyone, doctors administer a trial dose of baclofen to see how well a patient's muscles relax.
Why Should Spasticity Patients Come to the University of Maryland for Their Care?
We offer a comprehensive Spasticity Program run by medical specialists with extensive training and interest in spasticity. This specialized program is located at University of Maryland Rehabilitation & Orthopaedics Institute, formally Kernan Hospital, Maryland's leading Rehabilitation Hospital. The specialists use all of the resources available throughout the University of Maryland Medical System to help patients struggling with this complex problem achieve the best possible outcome.
For more information, call 1-800-492-5583.