William and Tuye Collins are coming up on an anniversary—though it's one they'd probably rather not have. On the evening of May 10, 2000, Tuye (pronounced TOO-yee) came home from a church gathering to find her husband sprawled on the bedroom floor. He had had a major stroke that severely impaired his ability to speak and swallow.
As if being paralyzed on the right side weren't hard enough, his right arm and leg were bent and his right foot frozen in a contracted position. In addition to the discomfort of his limbs frozen in such an unnatural position, William developed muscle cramps and the stiffness that comes with being unable to move around.
What William experienced is known as “post-stroke spasticity,” a persistent and involuntary spasm of the muscles that locks limbs, hands or feet into an uncomfortable and disabling contraction. Common examples are a clenched fist or a flexed elbow, or an ankle that doesn't bend well or a foot that turns in. In addition to loss of range of motion or ability to use the affected body part, these spasms may hurt—like a really bad Charley horse.
“Spasticity is increased muscle tension that occurs after a stroke or other injury to the brain,” explains Allison Brashear, M.D., chairman of neurology at Wake Forest University Baptist Medical Center in Winston-Salem, North Carolina. She adds that spasticity develops as people are recovering from a stroke and can develop anywhere from three months to a year after the stroke.
Doctors estimate that the condition occurs in roughly 20 percent to 50 percent of patients, typically those who experience severe numbness or paralysis right after their stroke.
EARLY SIGNS ARE SUBTLE
Early signals may be easy to miss, Brashear warns. “It comes on gradually, and often patients and caregivers are so concerned about the other devastating effects of the stroke, such as problems with walking or talking, that the more subtle things may get overlooked. I tell my patients to look for excessive tightness, such as difficulty opening your hand or putting on your shirt.”
A stroke occurs when there is a loss of blood flow that nourishes brain tissue, due to an obstructed blood vessel (ischemic stroke), or due to a rupture of a blood vessel within the brain causing leakage from the vessel into brain tissue (hemorrhagic stroke). Either way, the resulting disability depends on the part of the brain affected. A stroke that damages the upper portion of the brain known as the motor cortex impairs the brain's ability to properly calibrate and coordinate nerve impulses that control muscular activity, explains David Alexander, M.D., professor of neurology at the University of California, Los Angeles.
Doctors treating post-stroke spasticity focus on relieving contractions and any pain, maintaining as much range of motion as possible and relaxing the muscles in the affected areas. Treatment usually starts with physical or occupational therapy, then progresses to oral medications, and in the most stubborn cases, to injections or a pump that delivers medication directly to the spinal column.
Often several types of treatment are combined, such as physical therapy and one or more medications. There's no one-size-fits-all therapy; a patient's healthcare providers will consider his or her symptoms and overall health status to develop an appropriate treatment plan.
Proper management also includes treating any painful medical condition that might indirectly make the spasticity worse, for instance, urinary tract infection, gout or even ingrown toenails. The connection between pain and spasticity is not clear, but it's thought that pain signals to the spinal cord may add to the heightened level of nerve stimulation that produces spasticity to begin with.
KEEPING THINGS MOVING
Physical therapy usually involves exercises such as stretching or walking on a treadmill, which are designed to maintain range of motion and prevent permanent muscle shortening and damage to the joints. Some people benefit from special braces or splints that hold the muscle in a normal position and keep it from contracting. Others find that hot or cold packs help their muscles relax to make moving easier. William, now 63, benefits from a water aerobics class at his local YMCA three to four days a week. Tuye, 56, usually joins him.
Of the four oral medications commonly prescribed for spasticity, three block nerve signals that tell the muscles to contract (see “How muscles relax and contract”). These are: baclofen (Lioresal, Kemstro), tizanidine (Zanaflex, Sirdalud) and diazepam (Valium). Side effects of these drugs include sleepiness, confusion and possible impairment of liver function. The fourth drug, dantrolene (Dantrium), works directly on the muscle, essentially making it unresponsive to messages coming from the nerve. Dantrolene also may cause drowsiness, as well as muscle weakness, nausea or diarrhea.
“We tend to avoid diazepam because of its sedating and addictive properties, and I avoid dantrolene because it does not work on the source of the spasticity, which is the nerve,” says Alexander, who directs UCLA's neurological rehabilitation and research unit.
For her part, Brashear tends to avoid oral drugs because “when you swallow a pill the drug travels throughout the body, so there is a greater risk of side effects.” She adds that oral baclofen “helps people who have a more generalized spasticity, such as difficulty walking” but is not effective when the spasticity is isolated just to the fingers or the hand.
In such cases, baclofen may be administered into the spinal column through a catheter connected to a small pump implanted under the skin. While the potential for side effects is reduced and the drug is delivered directly to the neurons that are making muscles contract, the pump does have its drawbacks, Brashear says.
“[The pump] requires patients and family members [to be diligent about] refills and monitoring the dose, as well as repeated visits to the doctor.” She adds that since the pump is implanted surgically, the patient risks infection and heart or lung problems that are rare side effects of anesthesia—problems associated with any operation. And if the pump malfunctions, a repeat procedure will be needed to replace it.
A NEW WRINKLE FOR BOTOX
In March 2010, the Food and Drug Administration (FDA) approved the use of botulinum toxin (also known as Botox) injections to treat spasticity in the muscles of the elbow, wrist and fingers. Botox is a muscle relaxant—just as it smoothes wrinkles by relaxing the muscles of the face, it soothes spasticity by relaxing muscles in the upper extremities.
In 1996, Alexander coauthored the first study demonstrating that botulinum toxin could treat post-stroke spasticity. Six years later, Brashear and her colleagues published one of the clinical trials that persuaded the FDA to approve it for this use. “We showed that [Botox] improved patients' ability to clean their hands, dress themselves and engage in other activities that were important to them.”
“We've seen significant benefits in patients who come in with, for example, a clenched fist so they can't open their fingers to [wash] their palm, or people who can't get their arm through a sleeve because their elbow is bent,” says Brashear.
The injections are administered every three to six months, depending on how quickly the muscle tightness returns. Side effects are related mostly to the amount of drug injected into the muscle: High doses can loosen them up too much.
LIVING WITH SPASTICITY
Left untreated, spasticity can be painful and uncomfortable. It can disrupt a patient's sleep and make it difficult if not impossible to perform everyday tasks, such as bathing and dressing.
“One of my patients was thrilled because we helped relax her arm so she could pull her pants up by herself when she went to the bathroom,” says Brashear.
Botox injections have also helped William. Every three months, Brashear administers injections into his right arm. While the therapy “didn't restore the full range of motion,” says Tuye, the injections coupled with physical therapy “did help him move better.”
“I could see him getting stronger,” she adds. The muscle stiffness and cramps William suffered were also significantly relieved.
Because spasticity may affect walking and balance, and even the ability to wear shoes, the condition can hamper post-stroke rehab. “Patients often are discharged from the hospital with a splint, and by the time they come back for their follow-up appointment the splint no longer fits well, due to the changes in muscle tone,” Brashear explains.
“I've had patients come to me who have actually had their skin break down because they can't get their knees apart,” says Brashear.
And it's not just patients who suffer. “I think we've underestimated the impact on caregivers,” adds Brashear. “Treatments benefit caregivers too, because relieving the contractions makes caring for the patients so much easier. We not only improve a patient's ability to do things for themselves, but we also make it easier for caregivers to perform tasks such as dressing the patient.”
Still, the challenges presented by spasticity and other lingering effects of a stroke can be daunting. “I know what patients and caregivers are going through—the anger, the stress, the depression,” says Tuye. “I tell my husband every day, ‘you have to fight. You have to say, I can do it. I will do it.’ And I tell other people, ‘you can do this. Make up your mind to make a certain amount of progress every day. You can have a happy life. Don't give up.’”
How muscles relax and contract
There is a yin and a yang to how muscles work. A neuron that originates in the brain (known as the “upper motor neuron”) and travels to the spinal cord sends a signal to a second neuron that is connected to a muscle (known as the “lower motor neuron”) to coordinate the contraction and relaxation of muscles.
When the upper motor neuron sends a signal that makes the lower motor neuron to stop contracting the muscle, it relaxes. Without that signal from the upper motor neuron, the lower motor neuron can only make the muscle contract.
When loss of blood supply caused by an ischemic stroke damages upper motor neurons in the brain, the corresponding lower motor neurons never get the signal to allow a muscle to relax. As a result, the muscle no longer has full range of motion. As the muscle remains in this contracted position, tendons and soft tissues surrounding it tighten and shorten, making stretching painful. So the patient stops trying to stretch the muscle, which causes even more tightening. Without treatment, the muscle can eventually freeze into a painful and abnormal position.
© 2012 American Heart Association, Inc.