Dr MJ Bazos MD,
Patient Handout
Cerebral
Palsy
In the 1860s, an English surgeon named William
Little wrote the first medical descriptions of a puzzling disorder that struck
children in the first years of life, causing stiff, spastic muscles in their
legs and, to a lesser degree, their arms. These children had difficulty grasping
objects, crawling, and walking. They did not get better as they grew up nor did
they become worse. Their condition, which was called Little's disease for many
years, is now known as spastic diplegia. It is just one of several disorders
that affect control of movement and are grouped together under the term cerebral
palsy.
Because it seemed that many of
these children were born following complicated deliveries, Little suggested
their condition resulted from a lack of oxygen during birth. This oxygen
shortage damaged sensitive brain tissues controlling movement, he proposed. But
in 1897, the famous psychiatrist Sigmund Freud disagreed. Noting that children
with cerebral palsy often had other problems such as mental retardation, visual
disturbances, and seizures, Freud suggested that the disorder might sometimes
have roots earlier in life, during the brain's development in the womb.
"Difficult birth, in certain cases," he wrote, "is merely a symptom of deeper
effects that influence the development of the fetus."
Despite Freud's observation, the
belief that birth complications cause most cases of cerebral palsy was
widespread among physicians, families, and even medical researchers until very
recently. In the 1980s, however, scientists analyzed extensive data from a
government study of more than 35,000 births and were surprised to discover that
such complications account for only a fraction of cases—probably less than
10 percent. In most cases of cerebral palsy, no cause could be found. These
findings from the NINDS perinatal study have profoundly altered medical theories
about cerebral palsy and have spurred today's researchers to explore alternative
causes.
At the same time, biomedical
research has also led to significant changes in understanding, diagnosing, and
treating persons with cerebral palsy. Identification of infants with cerebral
palsy very early in life gives youngsters the best opportunity for developing to
their full capacity. Biomedical research has led to improved diagnostic
techniques—such as advanced brain imaging and modern gait
analysis—that are making this easier. Certain conditions known to cause
cerebral palsy, such as rubella (German measles) and jaundice, can now be
prevented or treated. Physical, psychological, and behavioral therapy that
assist with such skills as movement and speech and foster social and emotional
development can help children who have cerebral palsy to achieve and succeed.
Medications, surgery, and braces can often improve nerve and muscle
coordination, help treat associated medical problems, and either prevent or
correct deformities.
Much of the
research to improve medical understanding of cerebral palsy has been supported
by the National Institute of Neurological Disorders and Stroke (NINDS), one of
the federal government's National Institutes of Health. The NINDS is America's
leading supporter of biomedical research into cerebral palsy and other
neurological disorders. Through this publication, the NINDS hopes to help the
more than 4,500 American babies and infants diagnosed each year, their families,
and others concerned about cerebral palsy benefit from these research results.
What is Cerebral Palsy?
Cerebral palsy is an umbrella-like
term used to describe a group of chronic disorders impairing control of movement
that appear in the first few years of life and generally do not worsen over
time. The term cerebral refers to the brain's two halves, or hemispheres, and
palsy describes any disorder that impairs control of body movement. Thus, these
disorders are not caused by problems in the muscles or nerves. Instead, faulty
development or damage to motor areas in the brain disrupts the brain's ability
to adequately control movement and posture.
Symptoms of cerebral palsy lie along a
spectrum of varying severity. An individual with cerebral palsy may have
difficulty with fine motor tasks, such as writing or cutting with scissors;
experience trouble with maintaining balance and walking; or be affected by
involuntary movements, such as uncontrollable writhing motion of the hands or
drooling. The symptoms differ from one person to the next, and may even change
over time in the individual. Some people with cerebral palsy are also affected
by other medical disorders, including seizures or mental impairment. Contrary to
common belief, however, cerebral palsy does not always cause profound handicap.
While a child with severe cerebral palsy might be unable to walk and need
extensive, lifelong care, a child with mild cerebral palsy might only be
slightly awkward and require no special assistance. Cerebral palsy is not
contagious nor is it usually inherited from one generation to the next. At this
time, it cannot be cured, although scientific research continues to yield
improved treatments and methods of prevention.
How Many People Have This Disorder?
The United Cerebral Palsy Associations
estimate that more than 500,000 Americans have cerebral palsy. Despite advances
in preventing and treating certain causes of cerebral palsy, the number of
children and adults it affects has remained essentially unchanged or perhaps
risen slightly over the past 30 years. This is partly because more critically
premature and frail infants are surviving through improved intensive care.
Unfortunately, many of these infants have developmental problems of the nervous
system or suffer neurological damage. Research is under way to improve care for
these infants, as in ongoing studies of technology to alleviate troubled
breathing and trials of drugs to prevent bleeding in the brain before or soon
after birth.
What Are the Different
Forms?
Spastic diplegia, the disorder
first described by Dr. Little in the 1860s, is only one of several disorders
called cerebral palsy. Today doctors classify cerebral palsy into four broad
categories—spastic, athetoid, ataxic, and mixed forms—according to
the type of movement disturbance.
Spastic Cerebral Palsy: In this
form of cerebral palsy, which affects 70 to 80 percent of patients, the muscles
are stiffly and permanently contracted. Doctors will often describe which type
of spastic cerebral palsy a patient has based on which limbs are affected. The
names given to these types combine a Latin description of affected limbs with
the term plegia or paresis, meaning paralyzed or weak.
When both legs are affected by spasticity,
they may turn in and cross at the knees. As these individuals walk, their legs
move awkwardly and stiffly and nearly touch at the knees. This causes a
characteristic walking rhythm, known as the scissors gait.
Individuals with spastic hemiparesis may
also experience hemiparetic tremors, in which uncontrollable shaking affects the
limbs on one side of the body. If these tremors are severe, they can seriously
impair movement.
Athetoid, Or
Dyskinetic, Cerebral Palsy: This form of cerebral palsy is characterized by
uncontrolled, slow, writhing movements. These abnormal movements usually affect
the hands, feet, arms, or legs and, in some cases, the muscles of the face and
tongue, causing grimacing or drooling. The movements often increase during
periods of emotional stress and disappear during sleep. Patients may also have
problems coordinating the muscle movements needed for speech, a condition known
as dysarthria. Athetoid cerebral palsy affects about 10 to 20 percent of
patients.
Ataxic Cerebral
Palsy: This rare form affects the sense of balance and depth perception.
Affected persons often have poor coordination; walk unsteadily with a wide-based
gait, placing their feet unusually far apart; and experience difficulty when
attempting quick or precise movements, such as writing or buttoning a shirt.
They may also have intention tremor. In this form of tremor, beginning a
voluntary movement, such as reaching for a book, causes a trembling that affects
the body part being used and that worsens as the individual gets nearer to the
desired object. The ataxic form affects an estimated 5 to 10 percent of cerebral
palsy patients.
Mixed Forms: It
is common for patients to have symptoms of more than one of the previous three
forms. The most common mixed form includes spasticity and athetoid movements but
other combinations are also possible.
What Other Medical Disorders Are
Associated With Cerebral Palsy?
Many
individuals who have cerebral palsy have no associated medical disorders.
However, disorders that involve the brain and impair its motor function can also
cause seizures and impair an individual's intellectual development,
attentiveness to the outside world, activity and behavior, and vision and
hearing. Medical disorders associated with cerebral palsy include:
Mental impairment. About one-third
of children who have cerebral palsy are mildly intellectually impaired,
one-third are moderately or severely impaired, and the remaining third are
intellectually normal. Mental impairment is even more common among children with
spastic quadriplegia.
Seizures or
epilepsy. As many as half of all children with cerebral palsy have
seizures. During a seizure, the normal, orderly pattern of electrical activity
in the brain is disrupted by uncontrolled bursts of electricity. When seizures
recur without a direct trigger, such as fever, the condition is called epilepsy.
In the person who has cerebral palsy and epilepsy, this disruption may be spread
throughout the brain and cause varied symptoms all over the body—as in
tonic-clonic seizures—or may be confined to just one part of the brain and
cause more specific symptoms—as in partial seizures.
Tonic-clonic seizures generally cause
patients to cry out and are followed by loss of consciousness, twitching of both
legs and arms, convulsive body movements, and loss of bladder control.
Partial seizures are classified as simple
or complex. In simple partial seizures, the individual has localized symptoms,
such as muscle twitches, chewing movements, and numbness or tingling. In complex
partial seizures, the individual may hallucinate, stagger, perform automatic and
purposeless movements, or experience impaired consciousness or confusion.
Growth problems. A syndrome called
failure to thrive is common in children with moderate-to-severe cerebral palsy,
especially those with spastic quadriparesis. Failure to thrive is a general term
physicians use to describe children who seem to lag behind in growth and
development despite having enough food. In babies, this lag usually takes the
form of too little weight gain; in young children, it can appear as abnormal
shortness; in teenagers, it may appear as a combination of shortness and lack of
sexual development. Failure to thrive probably has several causes, including, in
particular, poor nutrition and damage to the brain centers controlling growth
and development.
In addition, the muscles
and limbs affected by cerebral palsy tend to be smaller than normal. This is
especially noticeable in some patients with spastic hemiplegia, because limbs on
the affected side of the body may not grow as quickly or as large as those on
the more normal side. This condition usually affects the hand and foot most
severely. Since the involved foot in hemiplegia is often smaller than the
unaffected foot even among patients who walk, this size difference is probably
not due to lack of use. Scientists believe the problem is more likely to result
from disruption of the complex process responsible for normal body growth.
Impaired vision or hearing. A large
number of children with cerebral palsy have strabismus, a condition in which the
eyes are not aligned because of differences in the left and right eye muscles.
In an adult, this condition causes double vision. In children, however, the
brain often adapts to the condition by ignoring signals from one of the
misaligned eyes. Untreated, this can lead to very poor vision in one eye and can
interfere with certain visual skills, such as judging distance. In some cases,
physicians may recommend surgery to correct strabismus.
Children with hemiparesis may have
hemianopia, which is defective vision or blindness that impairs the normal field
of vision of one eye. For example, when hemianopia affects the right eye, a
child looking straight ahead might have perfect vision except on the far right.
In homonymous hemianopia, the impairment affects the same part of the visual
field of both eyes.
Impaired hearing is
also more frequent among those with cerebral palsy than in the general
population.
Abnormal sensation and
perception. Some children with cerebral palsy have impaired ability to feel
simple sensations like touch and pain. They may also have stereognosia, or
difficulty perceiving and identifying objects using the sense of touch. A child
with stereognosia, for example, would have trouble identifying a hard ball,
sponge, or other object placed in his hand without looking at the object.
What Causes Cerebral Palsy?
Cerebral palsy is not one disease with
a single cause, like chicken pox or measles. It is a group of disorders that are
related but probably have different causes. When physicians try to uncover the
cause of cerebral palsy in an individual child, they look at the form of
cerebral palsy, the mother's and child's medical history, and onset of the
disorder.
About 10 to 20 percent of
children who have cerebral palsy acquire the disorder after birth. Acquired
cerebral palsy results from brain damage in the first few months or years of
life and often follows brain infections, such as bacterial meningitis or viral
encephalitis, or results from head injury—most often from a motor vehicle
accident, a fall, or child abuse.
Congenital cerebral palsy, on the
other hand, is present at birth, although it may not be detected for several
months. In most cases, the cause of congenital cerebral palsy is unknown. Thanks
to research, however, scientists have pinpointed some specific events during
pregnancy or around the time of birth that can damage motor centers in the
developing brain. Some of these causes of congenital cerebral palsy include:
Infections during pregnancy. German
measles, or rubella, is caused by a virus that can infect pregnant women and,
therefore, the fetus in the uterus, to cause damage to the developing nervous
system. Other infections that can cause brain injury in the developing fetus
include cytomegalovirus and toxoplasmosis.
Jaundice in the infant. Bile
pigments, compounds that are normally found in small amounts in the bloodstream,
are produced when blood cells are destroyed. When many blood cells are destroyed
in a short time, as in the condition called Rh incompatibility (see below), the
yellow-colored pigments can build up and cause jaundice. Severe, untreated
jaundice can damage brain cells.
Rh
incompatibility. In this blood condition, the mother's body produces immune
cells called antibodies that destroy the fetus's blood cells, leading to a form
of jaundice in the newborn.
Severe
oxygen shortage in the brain or trauma to the head during labor and
delivery. The newborn infant's blood is specially equipped to compensate for low
levels of oxygen, and asphyxia (lack of oxygen caused by interruption in
breathing or poor oxygen supply) is common in babies during the stresses of
labor and delivery. But if asphyxia severely lowers the supply of oxygen to the
infant's brain for lengthy periods, the child may develop brain damage called
hypoxic-ischemic encephalopathy. A significant proportion of babies with this
type of brain damage die, and others may develop cerebral palsy, which is then
often accompanied by mental impairment and seizures.
In the past, physicians and scientists
attributed most cases of cerebral palsy to asphyxia or other complications
during birth if they could not identify another cause. However, extensive
research by NINDS scientists and others has shown that very few babies who
experience asphyxia during birth develop encephalopathy soon after birth.
Research also shows that a large proportion of babies who experience asphyxia do
not grow up to have cerebral palsy or other neurological disorders. Birth
complications including asphyxia are now estimated to account for about 3 to 13
percent of congenital cerebral palsy cases.
Stroke. Bleeding in the brain has
several causes—including broken blood vessels in the brain, clogged blood
vessels, or abnormal blood cells—and is one form of stroke. Newborn
respiratory distress, a breathing disorder that is particularly common in
premature infants, is one cause. Although strokes are better known for their
effects on older adults, they can also occur in the fetus during pregnancy or
the newborn around the time of birth, damaging brain tissue and causing
neurological problems. Ongoing research is testing potential treatments that may
one day help prevent stroke in fetuses and newborns.
What Are the Risk Factors?
Research scientists have examined
thousands of expectant mothers, followed them through childbirth, and monitored
their children's early neurological development. As a result, they have
uncovered certain characteristics, called risk factors, that increase the
possibility that a child will later be diagnosed with cerebral palsy:
•Breech presentation. Babies with
cerebral palsy are more likely to present feet first, instead of head first, at
the beginning of labor.
•Complicated
labor and delivery. Vascular or respiratory problems of the baby during labor
and delivery may sometimes be the first sign that a baby has suffered brain
damage or that a baby's brain has not developed normally. Such complications can
cause permanent brain damage.
•Inborn malformations outside the
nervous system. Babies with physical birth defects—including faulty
formation of the spinal bones, hernia (a protrusion of organs through an
abnormal opening inside the body) in the groin area, or an abnormally small jaw
bone—are at an increased risk for cerebral palsy.
•Low Apgar score. The Apgar score (named
for anesthesiologist Virginia Apgar) is a numbered rating that reflects a
newborn's condition. To determine an Apgar score, doctors periodically check the
baby's heart rate, breathing, muscle tone, reflexes, and skin color in the first
minutes after birth. They then assign points; the higher the score, the more
normal the baby's condition. A low score at 10–20 minutes after delivery
is often considered an important sign of potential problems.
•Low birthweight and premature birth. The
risk of cerebral palsy is higher among babies who weigh less than 2500 grams (5
lbs., 7 1/2 oz.) at birth and among babies who are born less than 37 weeks into
pregnancy. This risk increases as birthweight falls. •Multiple births.
Twins, triplets, and other multiple births are linked to an increased risk of
cerebral palsy.
•Nervous system malformations. Some babies
born with cerebral palsy have visible signs of nervous system malformation, such
as an abnormally small head (microcephaly). This suggests that problems occurred
in the development of the nervous system while the baby was in the womb.
•Maternal bleeding or severe proteinuria
late in pregnancy. Vaginal bleeding during the sixth to ninth months of
pregnancy and severe proteinuria (the presence of excess proteins in the urine)
are linked to a higher risk of having a baby with cerebral palsy.
•Maternal hyperthyroidism, mental
retardation, or seizures. Mothers with any of these conditions are slightly more
likely to have a child with cerebral palsy.
•Seizures in the newborn. An infant who
has seizures faces a higher risk of being diagnosed, later in childhood, with
cerebral palsy.
Knowing these warning signs helps doctors keep a
close eye on children who face a higher risk for long-term problems in the
nervous system. However, parents should not become too alarmed if their child
has one or more of these factors. Most such children do not have and do not
develop cerebral palsy.
Can
Cerebral Palsy Be Prevented?
Several
of the causes of cerebral palsy that have been identified through research are
preventable or treatable:
•Head injury can be prevented by regular
use of child safety seats when driving in a car and helmets during bicycle
rides, and elimination of child abuse. In addition, common sense measures around
the household—like close supervision during bathing and keeping poisons
out of reach—can reduce the risk of accidental injury.
•Jaundice of newborn infants can be
treated with phototherapy. In phototherapy, babies are exposed to special blue
lights that break down bile pigments, preventing them from building up and
threatening the brain. In the few cases in which this treatment is not enough,
physicians can correct the condition with a special form of blood transfusion.
•Rh incompatibility is easily identified
by a simple blood test routinely performed on expectant mothers and, if
indicated, expectant fathers. This incompatibility in blood types does not
usually cause problems during a woman's first pregnancy, since the mother's body
generally does not produce the unwanted antibodies until after delivery. In most
cases, a special serum given after each childbirth can prevent the unwanted
production of antibodies. In unusual cases, such as when a pregnant woman
develops the antibodies during her first pregnancy or antibody production is not
prevented, doctors can help minimize problems by closely watching the developing
baby and, when needed, performing a transfusion to the baby while in the womb or
an exchange transfusion (in which a large volume of the baby's blood is removed
and replaced) after birth.
•Rubella, or German measles, can be
prevented if women are vaccinated against this disease before becoming pregnant.
In addition, it is always good to work toward a
healthy pregnancy through regular prenatal care and good nutrition and by
eliminating smoking, alcohol consumption, and drug abuse. Despite the best
efforts of parents and physicians, however, children will still be born with
cerebral palsy. Since in most cases the cause of cerebral palsy is unknown,
little can currently be done to prevent it. As investigators learn more about
the causes of cerebral palsy through basic and clinical research, doctors and
parents will be better equipped to help prevent this disorder.
What Are the Early Signs?
Early signs of cerebral palsy usually
appear before 3 years of age, and parents are often the first to suspect that
their infant is not developing motor skills normally. Infants with cerebral
palsy are frequently slow to reach developmental milestones, such as learning to
roll over, sit, crawl, smile, or walk. This is sometimes called developmental
delay.
Some affected children have
abnormal muscle tone. Decreased muscle tone is called hypotonia; the baby may
seem flaccid and relaxed, even floppy. Increased muscle tone is called
hypertonia, and the baby may seem stiff or rigid. In some cases, the baby has an
early period of hypotonia that progresses to hypertonia after the first 2 to 3
months of life. Affected children may also have unusual posture or favor one
side of their body.
Parents who are
concerned about their baby's development for any reason should contact their
physician, who can help distinguish normal variation in development from a
developmental disorder.
How
Is Cerebral Palsy Diagnosed?
Doctors
diagnose cerebral palsy by testing an infant's motor skills and looking
carefully at the infant's medical history. In addition to checking for those
symptoms described above—slow development, abnormal muscle tone, and
unusual posture—a physician also tests the infant's reflexes and looks for
early development of hand preference.
Reflexes are movements that the body
makes automatically in response to a specific cue. For example, if a newborn
baby is held on its back and tilted so the legs are above its head, the baby
will automatically extend its arms in a gesture, called the Moro reflex, which
looks like an embrace. Babies normally lose this reflex after they reach 6
months, but those with cerebral palsy may retain it for abnormally long periods.
This is just one of several reflexes that a physician can check.
Doctors can also look for hand
preference—a tendency to use either the right or left hand more often.
When the doctor holds an object in front and to the side of the infant, an
infant with hand preference will use the favored hand to reach for the object,
even when it is held closer to the opposite hand. During the first 12 months of
life, babies do not usually show hand preference. But infants with spastic
hemiplegia, in particular, may develop a preference much earlier, since the hand
on the unaffected side of their body is stronger and more useful.
The next step in diagnosing cerebral
palsy is to rule out other disorders that can cause movement problems. Most
important, doctors must determine that the child's condition is not getting
worse. Although its symptoms may change over time, cerebral palsy by definition
is not progressive. If a child is continuously losing motor skills, the problem
more likely springs from elsewhere—including genetic diseases, muscle
diseases, disorders of metabolism, or tumors in the nervous system. The child's
medical history, special diagnostic tests, and, in some cases, repeated
check-ups can help confirm that other disorders are not at fault.
The doctor may also order specialized
tests to learn more about the possible cause of cerebral palsy. One such test is
computed tomography, or CT, a sophisticated imaging technique that uses X rays
and a computer to create an anatomical picture of the brain's tissues and
structures. A CT scan may reveal brain areas that are underdeveloped, abnormal
cysts (sacs that are often filled with liquid) in the brain, or other physical
problems. With the information from CT scans, doctors may be better equipped to
judge the long-term outlook for an affected child.
Magnetic resonance imaging, or MRI, is
a relatively new brain imaging technique that is rapidly gaining widespread use
for identifying brain disorders. This technique uses a magnetic field and radio
waves, rather than X-rays. MRI gives better pictures of structures or abnormal
areas located near bone than CT.
A
third test that can expose problems in brain tissues is ultrasonography. This
technique bounces sound waves off the brain and uses the pattern of echoes to
form a picture, or sonogram, of its structures. Ultrasonography can be used in
infants before the bones of the skull harden and close. Although it is less
precise than CT and MRI scanning, this technique can detect cysts and structures
in the brain, is less expensive, and does not require long periods of
immobility.
Finally, physicians may
want to look for other conditions that are linked to cerebral palsy, including
seizure disorders, mental impairment, and vision or hearing problems.
When the doctor suspects a seizure
disorder, an electroencephalogram, or EEG, may be ordered. An EEG uses special
patches called electrodes placed on the scalp to record the natural electrical
currents inside the brain. This recording can help the doctor see telltale
patterns in the brain's electrical activity that suggests a seizure disorder.
Intelligence tests are often used to
determine if a child with cerebral palsy is mentally impaired. Sometimes,
however, a child's intelligence may be underestimated because problems with
movement, sensation, or speech due to cerebral palsy make it difficult for him
or her to perform well on these tests.
If problems with vision are suspected,
the doctor may refer the patient to an ophthalmologist for examination; if
hearing impairment seems likely, an otologist may be called in.
Identifying these accompanying conditions
is important and is becoming more accurate as ongoing research yields advances
that make diagnosis easier. Many of these conditions can then be addressed
through specific treatments, improving the long-term outlook for those with
cerebral palsy.
How Is Cerebral
Palsy Managed?
Cerebral palsy can not
be cured, but treatment can often improve a child's capabilities. In fact,
progress due to medical research now means that many patients can enjoy
near-normal lives if their neurological problems are properly managed. There is
no standard therapy that works for all patients. Instead, the physician must
work with a team of health care professionals first to identify a child's unique
needs and impairments and then to create an individual treatment plan that
addresses them.
Some approaches that
can be included in this plan are drugs to control seizures and muscle spasms,
special braces to compensate for muscle imbalance, surgery, mechanical aids to
help overcome impairments, counseling for emotional and psychological needs, and
physical, occupational, speech, and behavioral therapy. In general, the earlier
treatment begins, the better chance a child has of overcoming developmental
disabilities or learning new ways to accomplish difficult tasks.
The members of the treatment team for
a child with cerebral palsy should be knowledgeable professionals with a wide
range of specialties. A typical treatment team might include:
•a physician, such as a pediatrician, a
pediatric neurologist, or a pediatric physiatrist, trained to help
developmentally disabled children. This physician, often the leader of the
treatment team, works to synthesize the professional advice of all team members
into a comprehensive treatment plan, implements treatments, and follows the
patient's progress over a number of years.
•an orthopedist, a surgeon who specializes
in treating the bones, muscles, tendons, and other parts of the body's skeletal
system. An orthopedist might be called on to predict, diagnose, or treat muscle
problems associated with cerebral palsy.
•a physical therapist, who designs and
implements special exercise programs to improve movement and strength.
•an occupational therapist, who can help
patients learn skills for day-to-day living, school, and work.
•a speech and language pathologist, who
specializes in diagnosing and treating communication problems.
•a social worker, who can help patients
and their families locate community assistance and education programs.
•a psychologist, who helps patients and
their families cope with the special stresses and demands of cerebral palsy. In
some cases, psychologists may also oversee therapy to modify unhelpful or
destructive behaviors or habits.
•an educator, who may play an especially
important role when mental impairment or learning disabilities present a
challenge to education.
Individuals
who have cerebral palsy and their family or caregivers are also key members of
the treatment team, and they should be intimately involved in all steps of
planning, making decisions, and applying treatments. Studies have shown that
family support and personal determination are two of the most important
predictors of which individuals who have cerebral palsy will achieve long-term
goals.
Too often, however, physicians
and parents may focus primarily on an individual symptom—especially the
inability to walk. While mastering specific skills is an important focus of
treatment on a day-to-day basis, the ultimate goal is to help individuals grow
to adulthood and have maximum independence in society. In the words of one
physician, "After all, the real point of walking is to get from point A to point
B. Even if a child needs a wheelchair, what's important is that they're able to
achieve this goal."
What Specific
Treatments Are Available?
Physical, Behavioral, and Other
Therapies
Therapy—whether for
movement, speech, or practical tasks—is a cornerstone of cerebral palsy
treatment. The skills a 2-year-old needs to explore the world are very different
from those that a child needs in the classroom or a young adult needs to become
independent. Cerebral palsy therapy should be tailored to reflect these changing
demands.
Physical therapy usually begins
in the first few years of life, soon after the diagnosis is made. Physical
therapy programs use specific sets of exercises to work toward two important
goals: preventing the weakening or deterioration of muscles that can follow lack
of use (called disuse atrophy) and avoiding contracture, in which muscles become
fixed in a rigid, abnormal position.
Contracture is one of the most common
and serious complications of cerebral palsy. Normally, a child whose bones are
growing stretches the body's muscles and tendons through running and walking and
other daily activities. This ensures that muscles will grow at the same rate.
But in children with cerebral palsy, spasticity prevents this stretching and, as
a result, muscles do not grow fast enough to keep up with lengthening bones. The
resulting contracture can disrupt balance and trigger loss of previous
abilities. Physical therapy alone, or in combination with special braces
(sometimes called orthotic devices), works to prevent this complication by
stretching spastic muscles. For example, if a child has spastic hamstrings
(tendons located behind the knee), the therapist and parents should encourage
the child to sit with the legs extended to stretch them.
A third goal of some physical therapy
programs is to improve the child's motor development. A widespread program of
physical therapy that works toward this goal is the Bobath technique, named for
a husband and wife team who pioneered this approach in England. This program is
based on the idea that the primitive reflexes retained by many children with
cerebral palsy present major roadblocks to learning voluntary control. A
therapist using the Bobath technique tries to counteract these reflexes by
positioning the child in an opposing movement. So, for example, if a child with
cerebral palsy normally keeps his arm flexed, the therapist would repeatedly
extend it.
A second such approach to
physical therapy is "patterning," which is based on the principle that motor
skills should be taught in more or less the same sequence that they develop
normally. In this controversial approach, the therapist guides the child with
movement problems along the path of normal motor development. For example, the
child is first taught elementary movements like pulling himself to a standing
position and crawling before he is taught to walk—regardless of his age.
Some experts and organizations, including the American Academy of Pediatrics,
have expressed strong reservations about the patterning approach, because
studies have not documented its value.
Physical therapy is usually just one
element of an infant development program that also includes efforts to provide a
varied and stimulating environment. Like all children, the child with cerebral
palsy needs new experiences and interactions with the world around him in order
to learn. Stimulation programs can bring this valuable experience to the child
who is physically unable to explore.
As the child with cerebral palsy
approaches school age, the emphasis of therapy shifts away from early motor
development. Efforts now focus on preparing the child for the classroom, helping
the child master activities of daily living, and maximizing the child's ability
to communicate.
Physical therapy can
now help the child with cerebral palsy prepare for the classroom by improving
his or her ability to sit, move independently or in a wheelchair, or perform
precise tasks, such as writing. In occupational therapy, the therapist works
with the child to develop such skills as feeding, dressing, or using the
bathroom. This can help reduce demands on caregivers and boost self-reliance and
self-esteem. For the many children who have difficulty communicating, speech
therapy works to identify specific difficulties and overcome them through a
program of exercises. For example, if a child has difficulty saying words that
begin with "b," the therapist may suggest daily practice with a list of "b"
words, increasing their difficulty as each list is mastered. Speech therapy can
also work to help the child learn to use special communication devices, such as
a computer with voice synthesizers.
Behavioral therapy provides yet
another avenue to increase a child's abilities. This therapy, which uses
psychological theory and techniques, can complement physical, speech, or
occupational therapy. For example, behavioral therapy might include hiding a toy
inside a box to reward a child for learning to reach into the box with his
weaker hand. Likewise, a child learning to say his "b" words might be given a
balloon for mastering the word. In other cases, therapists may try to discourage
unhelpful or destructive behaviors, such as hair-pulling or biting, by
selectively presenting a child with rewards and praise during other, more
positive activities.
As a child with
cerebral palsy grows older, the need for and types of therapy and other support
services will continue to change. Continuing physical therapy addresses movement
problems and is supplemented by vocational training, recreation and leisure
programs, and special education when necessary. Counseling for emotional and
psychological challenges may be needed at any age, but is often most critical
during adolescence. Depending on their physical and intellectual abilities,
adults may need attendant care, living accommodations, transportation, or
employment opportunities.
Regardless
of the patient's age and which forms of therapy are used, treatment does not end
when the patient leaves the office or treatment center. In fact, most of the
work is often done at home. The therapist functions as a coach, providing
parents and patients with the strategy and drills that can help improve
performance at home, at school, and in the world. As research continues, doctors
and parents can expect new forms of therapy and better information about which
forms of therapy are most effective for individuals with cerebral palsy.
Drug Therapy
Physicians usually prescribe drugs for
those who have seizures associated with cerebral palsy, and these medications
are very effective in preventing seizures in many patients. In general, the
drugs given to individual patients are chosen based on the type of seizures,
since no one drug controls all types. However, different people with the same
type of seizure may do better on different drugs, and some individuals may need
a combination of two or more drugs to achieve good seizure control.
Drugs are also sometimes used to
control spasticity, particularly following surgery. The three medications that
are used most often are diazepam, which acts as a general relaxant of the brain
and body; baclofen, which blocks signals sent from the spinal cord to contract
the muscles; and dantrolene, which interferes with the process of muscle
contraction. Given by mouth, these drugs can reduce spasticity for short
periods, but their value for long-term control of spasticity has not been
clearly demonstrated. They may also trigger significant side effects, such as
drowsiness, and their long-term effects on the developing nervous system are
largely unknown. One possible solution to avoid such side effects may lie in
current research to explore new routes for delivering these drugs.
Patients with athetoid cerebral palsy
may sometimes be given drugs that help reduce abnormal movements. Most often,
the prescribed drug belongs to a group of chemicals called anticholinergics that
work by reducing the activity of acetylcholine. Acetylcholine is a chemical
messenger that helps some brain cells communicate and that triggers muscle
contraction. Anticholinergic drugs include trihexyphenidyl, benztropine, and
procyclidine hydrochloride.
Occasionally, physicians may use
alcohol "washes"—or injections of alcohol into a muscle—to reduce
spasticity for a short period. This technique is most often used when physicians
want to correct a developing contracture. Injecting alcohol into a muscle that
is too short weakens the muscle for several weeks and gives physicians time to
work on lengthening the muscle through bracing, therapy, or casts. In some
cases, if the contracture is detected early enough, this technique may avert the
need for surgery.
Surgery
Surgery is often recommended when
contractures are severe enough to cause movement problems. In the operating
room, surgeons can lengthen muscles and tendons that are proportionately too
short. First, however, they must determine the exact muscles at fault, since
lengthening the wrong muscle could make the problem worse.
Finding problem muscles that need
correction can be a difficult task. To walk two strides with a normal gait, it
takes more than 30 major muscles working at exactly the right time and exactly
the right force. A problem in any one muscle can cause abnormal gait.
Furthermore, the natural adjustments the body makes to compensate for muscle
problems can be misleading. A new tool that enables doctors to spot gait
abnormalities, pinpoint problem muscles, and separate real problems from
compensation is called gait analysis. Gait analysis combines cameras that record
the patient while walking, computers that analyze each portion of the patient's
gait, force plates that detect when feet touch the ground, and a special
recording technique that detects muscle activity (known as electromyography).
Using these data, doctors are better equipped to intervene and correct
significant problems. They can also use gait analysis to check surgical results.
Because lengthening a muscle makes it
weaker, surgery for contractures is usually followed by months of recovery. For
this reason, doctors try to fix all of the affected muscles at once when it is
possible or, if more than one surgical procedure is unavoidable, they may try to
schedule operations close together.
A
second surgical technique, known as selective dorsal root rhizotomy, aims to
reduce spasticity in the legs by reducing the amount of stimulation that reaches
leg muscles via nerves. In the procedure, doctors try to locate and selectively
sever overactivated nerves controlling leg muscles. Although there is scientific
controversy over how selective this technique actually is, recent research
results suggest it can reduce spasticity in some patients, particularly those
who have spastic diplegia. Ongoing research is evaluating this surgery's
effectiveness.
Experimental surgical
techniques include chronic cerebellar stimulation and stereotaxic thalamotomy.
In chronic cerebellar stimulation, electrodes are implanted on the surface of
the cerebellum—the part of the brain responsible for coordinating
movement—and are used to stimulate certain cerebellar nerves. While it was
hoped that this technique would decrease spasticity and improve motor function,
results of this invasive procedure have been mixed. Some studies have reported
improvements in spasticity and function, others have not.
Stereotaxic thalamotomy involves
precise cutting of parts of the thalamus, which serves as the brain's relay
station for messages from the muscles and sensory organs. This has been shown
effective only for reducing hemiparetic tremors (see glossary).
Mechanical Aids
Whether they are as humble as velcro
shoes or as advanced as computerized communication devices, special machines and
gadgets in the home, school, and workplace can help the child or adult with
cerebral palsy overcome limitations.
The
computer is probably the most dramatic example of a new device that can make a
difference in the lives of those with cerebral palsy. For example, a child who
is unable to speak or write but can make head movements may be able to learn to
control a computer using a special light pointer that attaches to a headband.
Equipped with a computer and voice synthesizer, this child could communicate
with others. In other cases, technology has led to new versions of old devices,
such as the traditional wheelchair and its modern offspring that runs on
electricity.
Many such devices are
products of engineering research supported by private foundations and other
groups.
What Other Major Problems
Are Associated With Cerebral Palsy?
A
common complication is incontinence, caused by faulty control over the muscles
that keep the bladder closed. Incontinence can take the form of bed-wetting
(also known as eneuresis), uncontrolled urination during physical activities (or
stress incontinence), or slow leaking of urine from the bladder. Possible
medical treatments for incontinence include special exercises, biofeedback,
prescription drugs, surgery, or surgically implanted devices to replace or aid
muscles. Specially designed undergarments are also available.
Poor control of the muscles of the throat,
mouth and tongue sometimes leads to drooling. Drooling can cause severe skin
irritation and, because it is socially unacceptable, can lead to further
isolation of affected children from their peers. Although numerous treatments
for drooling have been tested over the years, there is no one treatment that
always helps. Drugs called anticholinergics can reduce the flow of saliva but
may cause significant side effects, such as mouth dryness and poor digestion.
Surgery, while sometimes effective, carries the risk of complications, including
worsening of swallowing problems. Some patients benefit from a technique called
biofeedback that can tell them when they are drooling or having difficulty
controlling muscles that close the mouth. This kind of therapy is most likely to
work if the patient has a mental age of more than 2 or 3 years, is motivated to
control drooling, and understands that drooling is not socially acceptable.
Difficulty with eating and
swallowing—also triggered by motor problems in the mouth—can cause
poor nutrition. Poor nutrition, in turn, may make the individual more vulnerable
to infections and cause or aggravate "failure to thrive"—a lag in growth
and development that is common among those with cerebral palsy. To make
swallowing easier, the caregiver may want to prepare semisolid food, such as
strained vegetables and fruits. Proper position, such as sitting up while eating
or drinking and extending the individual's neck away from the body to reduce the
risk of choking, is also helpful. In severe cases of swallowing problems and
malnutrition, physicians may recommend tube feeding, in which a tube delivers
food and nutrients down the throat and into the stomach, or gastrostomy, in
which a surgical opening allows a tube to be placed directly into the stomach.
What Research Is Being Done?
Investigators from many arenas of
medicine and health are using their expertise to help improve treatment and
prevention of cerebral palsy. Much of their work is supported through the
National Institute of Neurological Disorders and Stroke (NINDS), the National
Institute of Child Health and Human Development, other agencies within the
Federal Government, nonprofit groups such as the United Cerebral Palsy Research
Foundation, and private institutions.
The ultimate hope for overcoming
cerebral palsy lies with prevention. In order to prevent cerebral palsy,
however, scientists must first understand the complex process of normal brain
development and what can make this process go awry.
Between early pregnancy and the first
months of life, one cell divides to form first a handful of cells, and then
hundreds, millions, and, eventually, billions of cells. Some of these cells
specialize to become brain cells. These brain cells specialize into different
types and migrate to their appropriate site in the brain. They send out branches
to form crucial connections with other brain cells. Ultimately, the most complex
entity known to us is created: a human brain with its billions of interconnected
neurons.
Mounting evidence is pointing
investigators toward this intricate process in the womb for clues about cerebral
palsy. For example, a group of researchers has recently observed that more than
one-third of children who have cerebral palsy also have missing enamel on
certain teeth. This tooth defect can be traced to problems in the early months
of fetal development, suggesting that a disruption at this period in development
might be linked both to this tooth defect and to cerebral palsy.
As a result of this and other
research, many scientists now believe that a significant number of children
develop cerebral palsy because of mishaps early in brain development. They are
examining how brain cells specialize, how they know where to migrate, how they
form the right connections—and they are looking for preventable factors
that can disrupt this process before or after birth.
Scientists are also scrutinizing other
events—such as bleeding in the brain, seizures, and breathing and
circulation problems—that threaten the brain of the newborn baby. Through
this research, they hope to learn how these hazards can damage the newborn's
brain and to develop new methods for prevention.
Some newborn infants, for example,
have life-threatening problems with breathing and blood circulation. A recently
introduced treatment to help these infants is extracorporeal membrane
oxygenation, in which blood is routed from the patient to a special machine that
takes over the lungs' task of removing carbon dioxide and adding oxygen.
Although this technique can dramatically help many such infants, some scientists
have observed that a substantial fraction of treated children later experience
long-term neurological problems, including developmental delay and cerebral
palsy. Investigators are studying infants through pregnancy, delivery, birth,
and infancy, and are tracking those who undergo this treatment. By observing
them at all stages of development, scientists can learn whether their problems
developed before birth, result from the same breathing problems that made them
candidates for the treatment, or spring from errors in the treatment itself.
Once this is determined, they may be able to correct any existing problems or
develop new treatment methods to prevent brain damage.
Other scientists are exploring how
brain insults like hypoxic-ischemic encephalopathy (brain damage from a shortage
of oxygen or blood flow), bleeding in the brain, and seizures can cause the
abnormal release of brain chemicals and trigger brain damage. For example,
research has shown that bleeding in the brain unleashes dangerously high amounts
of a brain chemical called glutamate. While glutamate is normally used in the
brain for communication, too much glutamate overstimulates the brain's cells and
causes a cycle of destruction. Scientists are now looking closely at glutamate
to detect how its release harms brain tissue and spreads the damage from stroke.
By learning how such brain chemicals that normally help us function can hurt the
brain, scientists may be equipped to develop new drugs that block their harmful
effects.
In related research, some
investigators are already conducting studies to learn if certain drugs can help
prevent neonatal stroke. Several of these drugs seem promising because they
appear to reduce the excess production of potentially dangerous chemicals in the
brain and may help control brain blood flow and volume. Earlier research has
linked sudden changes in blood flow and volume to stroke in the newborn.
Low birthweight itself is also the
subject of extensive research. In spite of improvements in health care for some
pregnant women, the incidence of low birth-weight babies born each year in the
United States remains at about 7 1/2 percent. Some scientists currently
investigating this serious health problem are working to understand how
infections, hormonal problems, and genetic factors may increase a woman's
chances of giving birth prematurely. They are also conducting more applied
research that could yield: 1) new drugs that can safely delay labor, 2) new
devices to further improve medical care for premature infants, and 3) new
insight into how smoking and alcohol consumption can disrupt fetal development.
While this research offers hope for
preventing cerebral palsy in the future, ongoing research to improve treatment
brightens the outlook for those who must face the challenges of cerebral palsy
today. An important thrust of such research is the evaluation of treatments
already in use so that physicians and parents have the information they need to
choose the best therapy. A good example of this effort is an ongoing
NINDS-supported study that promises to yield new information about which
patients are most likely to benefit from selective dorsal root rhizotomy, a
recently introduced surgery that is becoming increasingly in demand for
reduction of spasticity.
Similarly,
although physical therapy programs are a popular and widespread approach to
managing cerebral palsy, little scientific evidence exists to help physicians,
other health professionals, and parents determine how well physical therapy
works or to choose the best approach among many. Current research on cerebral
palsy aims to provide this information through careful studies that compare the
abilities of children who have had physical and other therapy with those who
have not.
As part of this effort,
scientists are working to create new measures to judge the effectiveness of
treatment, as in ongoing research to precisely identify the specific brain areas
responsible for movement may yield one such approach. Using magnetic pulses,
researchers can locate brain areas that control specific actions, such as
raising an arm or lifting a leg, and construct detailed maps. By comparing
charts made before and after therapy among children who have cerebral palsy,
researchers may gain new insights into how therapy affects the brain's
organization and new data about its effectiveness.
Investigators are also working to
develop new drugs—and new ways of using existing drugs—to help
relieve cerebral palsy's symptoms. In one such set of studies, early research
results suggest that doctors may improve the effectiveness of the
anti-spasticity drug called baclofen by giving the drug through spinal
injections, rather than by mouth. In addition, scientists are also exploring the
use of tiny implanted pumps that deliver a constant supply of anti-spasticity
drugs into the fluid around the spinal cord, in the hope of improving these
drugs' effectiveness and reducing side effects, such as drowsiness.
Other experimental drug development
efforts are exploring the use of minute amounts of the familiar toxin called
botulinum. Ingested in large amounts, this toxin is responsible for botulism
poisoning, in which the body's muscles become paralyzed. Injected in tiny
amounts, however, this toxin has shown early promise in reducing spasticity in
specific muscles.
A large research
effort is also directed at producing more effective, nontoxic drugs to control
seizures. Through its Antiepileptic Drug Development Program, the NINDS screens
new compounds developed by industrial and university laboratories around the
world for toxicity and anticonvulsant activity and coordinates clinical studies
of efficacy and safety. To date, this program has screened more than 13,000
compounds and, as a result, five new antiepileptic drugs—carbamazepine,
clonazepam, valproate, clorazepate, and felbamate—have been approved for
marketing. A new project within the program is exploring how the structure of a
given antiseizure medication relates to its effectiveness. If successful, this
project may enable scientists to design better antiseizure medications more
quickly and cheaply.
As researchers
continue to explore new treatments for cerebral palsy and to expand our
knowledge of brain development, we can expect significant medical advances to
prevent cerebral palsy and many other disorders that strike in early life.
Magnesium Sulfate and Decreased
Risk of Cerebral Palsy
Research
conducted and supported by the National Institute of Neurological Disorders and
Stroke (NINDS) continuously seeks to uncover new clues about cerebral palsy
(CP). Recently, investigators from the NINDS and the California Birth Defects
Monitoring Program (CBDMP) presented data suggesting that very low birthweight
babies have a decreased incidence of CP when their mothers are treated with
magnesium sulfate soon before giving birth. The results of this study, which
were based on observations of a group of children born in four Northern
California counties, were published in the February 1995 issue of Pediatrics.*
Low birthweight babies are 100 times more
likely to develop CP than normal birthweight infants. If further research
confirms the study's findings, use of magnesium sulfate may prevent 25 percent
of the cases of CP in the approximately 52,000 low birthweight babies born each
year in the United States.
Magnesium is a
natural compound that is responsible for numerous chemical processes within the
body and brain. Obstetricians in the United States often administer magnesium
sulfate, an inexpensive form of the compound, to pregnant women to prevent
preterm labor and high blood pressure brought on by pregnancy. The drug,
administered intravenously in the hospital, is considered safe when given under
medical supervision.
Scientists speculate
that magnesium may play a role in brain development and possibly prevent
bleeding inside the brains of preterm infants. Previous research has shown that
magnesium may protect against brain bleeding in very premature infants. Animal
studies have demonstrated that magnesium given after a traumatic brain injury
can reduce the severity of brain damage.
Despite these encouraging research
findings, pregnant women should not change their magnesium intake because the
effects of high doses have not yet been studied and the possible risks and
benefits are not known.
Glossary
Apgar score. A numbered score doctors
use to assess a baby's physical state at the time of birth.
Apraxia. Impaired ability to carry out
purposeful movements in an individual who does not have significant motor
problems.
Asphyxia. Lack of oxygen due to
trouble with breathing or poor oxygen supply in the air.
Bile pigments. Yellow-colored substances
produced by the human body as a by-product of digestion.
Cerebral. Relating to the two hemispheres
of the human brain.
Computed tomography
(CT). An imaging technique that uses X rays and a computer to create a picture
of the brain's tissues and structures.
Congenital. Present at birth.
Contracture. A condition in which muscles
become fixed in a rigid, abnormal position causing distortion or deformity.
Dysarthria. Problems with speaking caused
by difficulty moving or coordinating the muscles needed for speech.
Electroencephalogram (EEG). A technique
for recording the pattern of electrical currents inside the brain.
Electromyography. A special recording
technique that detects muscle activity.
Failure to thrive. A condition
characterized by lag in physical growth and development.
Gait analysis. A technique that uses
camera recording, force plates, electromyography, and computer analysis to
objectively measure an individual's pattern of walking.
Gastrostomy. A surgical procedure to
create an artificial opening in the stomach.
Hemianopia. Defective vision or blindness
that impairs half of the normal field of vision.
Hemiparetic tremors. Uncontrollable
shaking affecting the limbs on the spastic side of the body in those who have
spastic hemiplegia.
Hypertonia. Increased
tone.
Hypotonia. Decreased tone.
Hypoxic-ischemic encephalopathy. Brain
damage caused by poor blood flow or insufficient oxygen supply to the brain.
Jaundice. A blood disorder caused by the
abnormal buildup of bile pigments in the bloodstream.
Magnetic resonance imaging (MRI). An
imaging technique which uses radio waves, magnetic fields, and computer analysis
to create a picture of body tissues and structures.
Neonatal hemorrhage. Bleeding of brain
blood vessels in the newborn.
Orthotic
devices. Special devices, such as splints or braces, used to treat problems of
the muscles, ligaments, or bones of the skeletal system.
Paresis or plegia. Weakness or paralysis.
In cerebral palsy, these terms are typically combined with another phrase that
describes the distribution of paralysis and weakness, e.g., paraparesis.
Palsy. Paralysis, or problems in the
control of voluntary movement.
Reflexes.
Movements that the body makes automatically in response to a specific cue.
Rh incompatibility. A blood condition in
which antibodies in a pregnant woman's blood can attack fetal blood cells,
impairing the fetus's supply of oxygen and nutrients.
Rubella. Also known as German measles,
rubella is a viral infection that can damage the nervous system in the
developing fetus.
Selective dorsal root
rhizotomy. A surgical procedure in which selected nerves are severed to reduce
spasticity in the legs.
Spastic diplegia.
A form of cerebral palsy in which both arms and both legs are affected, the legs
being more severely affected.
Spastic
hemiplegia (or hemiparesis). A form of cerebral palsy in which spasticity
affects the arm and leg on one side of the body.
Spastic paraplegia (or paraparesis). A
form of cerebral palsy in which spasticity affects both legs but the arms are
relatively or completely spared.
Spastic
quadriplegia (or quadriparesis). A form of cerebral palsy in which all four
limbs are affected equally.
Stereognosia.
Difficulty perceiving and identifying objects using the sense of touch.
Strabismus. Misalignment of the eyes.
Ultrasonography. A technique that bounces
sound waves off of tissues and structures and uses the pattern of echoes to form
an image, called a sonogram.