Spasticity is an
uncontrollable muscle tightness in an arm or leg that can
cause pain and affect movement.
The involuntary muscle contraction of spasticity is a common
physical response to the brain injury caused
by stroke. If the brain injury resolves and voluntary
movement returns, spasticity may diminish, restoring the
usefulness of the limb. However, with stroke the damage is
often permanent, so the spasticity must be treated
independently. Spasticity usually coexists with weakness.
In a stroke
survivor with spasticity, the reflex in the muscle does not
obey the nervous system's order to relax, and remains
contracted. The brain injury from the stroke causes the
reflex arc to lose control of the nervous system, similar to
a parent who has lost control over a hyper excitable child
running wildly around a room. In a healthy brain the reflex
tells the muscles to relax and be still until told to
contract.
Following stroke, spasticity is most common in the arm. It
can cause a characteristic posture of a tight fist, bent
elbow and arm pressed against the chest. This posture can
seriously interfere with a stroke survivor's ability to
perform daily activities such as dressing. Spasticity in the
leg usually causes a stiff knee and
pointed foot. |
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What are Symptoms or
Effects? |
- Stiffness
in the arms, fingers or legs.
- Painful
muscle spasms.
- A series
of involuntary rhythmic contractions and relaxations in a
muscle or group of muscles that lead to uncontrollable
movement or jerking, called clonus.
- Abnormal
posture
- Hyperexcitable reflexes
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What Treatments are
Available? |
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Treatment for
spasticity is often progressive, starting from the lowest
level of risk or side effects; only moving on to other
options if treatment is ineffective and quality of life is
significantly decreased. It's important for patients to
discuss appropriate treatments for their individual cases
with their physicians. |
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A muscle
stretching program performed at least one or two times daily
by moving the affected limb through a full range of motion
is considered basic management for spasticity. |
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Temporary Strategies |
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If stretching is
not sufficient, casts and splints may be helpful in
improving range of motion in spastic limbs. Other short-term
techniques include applying cold or local anesthesia to
reduce spastic tone. |
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Oral Medication |
Because of the
wide range of problems caused by spasticity, it's doubtful
that any one medication will help all effects of spasticity.
In addition, all drugs used in the treatment of spasticity
have the potential for side effects which should be weighed
against their benefit.
Baclofen (Lioresal) decreases muscle
spasticity by inhibiting the stretch reflex, reducing flexor
spasms, and increasing range of motion. It may also improve
bladder control in selected patients. Side effects may
include hallucinations, confusion, sedation, loss of muscle
tone, poor muscular coordination and weakness in
nonaffected muscles.
Dantrolene sodium (Dantrium) weakens spastic
muscles and has little effect on normal muscles. Dantrolene
may cause drowsiness, depression, nausea, vomiting,
dizziness, diarrhea and liver malfunctioning.
Tizanidine hydrochloride (Zanaflex)is a
recently approved treatment for spasticity. Clinical trials
have shown it to be equal to baclofen in reducing
spasticity, but better tolerated. In addition, studies have
demonstrated that Zanaflex, unlike all other oral spasticity
medications, does not cause muscle weakness. Side effects
include low blood pressure, sleepiness and dry mouth. |
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Spinal Medications |
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Intrathecal Baclofen (ITB) Therapy delivers a liquid
form of baclofen directly to the spinal fluid via a small
pump that is surgically placed under the skin. Since the
medication does not circulate throughout the body, only
small doses are required to be effective. This reduces the side
effects common with oral baclofen. ITB Therapy has been
shown to be effective in people with severe spasticity,
including some who have not had good results with oral
medications. The most common device-related complications
are kinks, dislodgments, or breaks in the catheter that
delivers the drug from the device into the spinal fluid. The
most common ITB Therapy drug side effects include loose
muscles, drowsiness, nausea/vomiting headache and dizziness. |
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Botulinum
toxin (Botox) is injected into the affected muscles
to relax their spasticity by blocking the chemical impulses
that cause muscles to contract. While oral medication
affects multiple muscle groups in the body, Botox injections
target only the specific muscles which are injected. A
single injection can relax affected muscles for three to six
months before the effects wear off. Side effects include
soreness or swelling at the injection site, fatigue, excess
muscle weakness and possible antibody formation. Botulinum
toxin is most effective for managing spasticity in specific
limbs or muscle groups. Clinical studies have shown the drug
to be effective in patients with spasticity. However, it has
not yet been approved by the Food and Drug Administration
for the treatment of spasticity.
Phenol is a type of alcohol which chemically
blocks nerves in the affected muscles to reduce the
spasticity. It is similar to botulinum toxin in length of
effectiveness and patient selection. Neither block is
suitable for patients with full-body spasticity because the
treatment is technologically difficult. Phenol injections
may cause pain. |
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Orthopedic Surgery |
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Surgery on
specific affected muscles can improve isolated tasks in
patients with severe spasticity. One of the most dramatic
surgical procedures to improve the ability to walk is the
split anterior tibial transfer (SPLATT). In a SPLATT
operation, the surgeon splits a tendon that makes the foot
turn inward and moves half of the tendon to the outside of
the foot where it can help straighten and balance the foot
as a walking surface. Surgery to cut and transfer tendons is
also performed on other problematic muscles. |
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Neurosurgery |
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Neurosurgery is
reserved as a last resort when other methods fail. Nerves
can be surgically cut to create a more permanent disruption
of nerve function than a block. In a drastic surgery called
rhizotomies, nerves are severed as they leave or enter the
spinal cord, interrupting the spinal reflex arc and ending
spasticity permanently. |
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