CEREBRAL PALSY DEFINITION
The term cerebral palsy refers to any one of a number of neurological disorders that appear in infancy or early childhood and permanently affect body movement and muscle coordination but don’t worsen over time. Even though cerebral palsy affects muscle movement, it isn’t caused by problems in the muscles or nerves. It is caused by abnormalities in parts of the brain that control muscle movements. The majority of children with cerebral palsy are born with it, although it may not be detected until months or years later. The early signs of cerebral palsy usually appear before a child reaches 3 years of age. The most common are a lack of muscle coordination when performing voluntary movements (ataxia); stiff or tight muscles and exaggerated reflexes (spasticity); walking with one foot or leg dragging; walking on the toes, a crouched gait, or a “scissored” gait; and muscle tone that is either too stiff or too floppy. A small number of children have cerebral palsy as the result of brain damage in the first few months or years of life, brain infections such as bacterial meningitis or viral encephalitis, or head injury from a motor vehicle accident, a fall, or child abuse.
CEREBRAL PALSY CAUSES
Congenital cerebral palsy results from brain injury during a baby’s development in the womb. It is present at birth, although it may not be detected for months. It is responsible for CP in about 70% of the children who have it. An additional 20% are diagnosed with congenital cerebral palsy due to a brain injury during the birthing process. In most cases, the cause of congenital cerebral palsy is unknown. Some possible causes are:
- Congenital cerebral palsy results from brain injury during a baby’s development in the womb. It is present at birth, although it may not be detected for months. It is responsible for CP in about 70% of the children who have it. An additional 20% are diagnosed with congenital cerebral palsy due to a brain injury during the birthing process. In most cases, the cause of congenital cerebral palsy is unknown. Some possible causes are:
- Infections during pregnancy that may damage a fetus’ developingnervous system. These include rubella (German measles), cytomegalovirus (a herpes-type virus), and toxoplasmosis (an infection caused by a parasite that can be carried in cat feces or inadequately cooked meat). Other infections in pregnant women that may go undetected are being recognized now as an important cause of developmental brain damage in the fetus.
- Severe jaundice in the infant. Jaundice is caused by excessivebilirubin in the blood. Normally, bilirubin is filtered out by the liver. But often, newborns’ livers need a few days to start doing this effectively, so it’s not uncommon for infants to have jaundice for a few days after birth. In most cases, phototherapy (light therapy) clears up jaundice, and there are no lasting health effects. However, in rare cases, severe, untreated jaundice can damage brain cells.
- Rh incompatibility between mother and infant. In this blood condition, the mother’s body produces antibodies that destroy the fetus’s blood cells. This, in turn, leads to a form of jaundice in thenewborn and may cause brain damage.
- The physical and metabolic trauma of being born. This can precipitate brain damage in a fetus whose health has been threatened during development.
- Severe oxygen deprivation to the brain or significant trauma to the head during labor and delivery.
CEREBRAL PALSY PATHOPHYSIOLOGY
Varies depending on the aetiology, which includes overt structural lesions of the brain or less visible lesions that result from antenatal, neonatal, and postnatal events. Other factors such as toxins, infections, multiple births, and maternal health also exert an influence. Postnatal brain MRIs show abnormalities in up to 80% of established cases of CP.
Severe compromise in oxygen and/or cerebral perfusion following birth trauma leads to hypoxic-ischaemic encephalopathy. A similar neonatal encephalopathy can also occur with inflammatory conditions such as maternal fever and infection. Between 26 and 34 weeks’ gestation, selective vulnerability of the periventricular white matter (e.g., to periventricular leukomalacia [PVL] or periventricular haemorrhage) occurs involving the internal capsule. Fetal insults at this time may result in spastic diplegia. These white matter changes are also found in 71.3% of children with spastic diplegia, 34.1% with spastic hemiplegia, and 35.1% of those with spastic quadriplegia, despite 25% of these cases being term births.
CEREBRAL PALSY SYMPTOMS
Signs and symptoms can vary greatly. Movement and coordination problems associated with cerebral palsy may include:
- Variations in muscle tone, such as being either too stiff or too floppy
- Stiff muscles and exaggerated reflexes (spasticity)
- Stiff muscles with normal reflexes (rigidity)
- Lack of muscle coordination (ataxia)
- Tremors or involuntary movements
- Slow, writhing movements (athetosis)
- Delays in reaching motor skills milestones, such as pushing up on arms, sitting up alone or crawling
- Favoring one side of the body, such as reaching with only one hand or dragging a leg while crawling
- Difficulty walking, such as walking on toes, a crouched gait, a scissors-like gait with knees crossing or a wide gait
- Excessive drooling or problems with swallowing
- Difficulty with sucking or eating
- Delays in speech development or difficulty speaking
- Difficulty with precise motions, such as picking up a crayon or spoon
The disability associated with cerebral palsy may be limited primarily to one limb or one side of the body, or it may affect the whole body. The brain disorder causing cerebral palsy doesn’t change with time, so the symptoms usually don’t worsen with age, although the shortening of muscles and muscle rigidity may worsen if not treated aggressively.
OTHER NEUROLOGICAL PROBLEMS
Brain abnormalities associated with cerebral palsy also may contribute to other neurological problems. People with cerebral palsy may also have:
- Difficulty with vision and hearing
- Intellectual disabilities
- Abnormal touch or pain perceptions
- Oral diseases
- Mental health (psychiatric) conditions
- Urinary incontinence
CEREBRAL PALSY DIAGNOSIS
A definitive test for cerebral palsy — or CP — does not exist at this time. The diagnosis is based on a child’s medical history and a physical exam.
Doctors diagnose CP by testing the infant’s motor skills, looking for characteristic symptoms, and considering the child’s medical history. They also may use computed tomography (CT) scans or magnetic resonance imaging (MRI) scans to look for abnormalities in the infant’s brain. Certain lab tests may help rule out various progressive biochemical disorders that involve the motor system, such as Tay-Sachs disease.
A CP diagnosis can be difficult, because infants may have more than one type of the disease and their symptoms may change during their first few years, making an exact diagnosis impossible.
CP is easier to diagnose in more severely affected children. In these children, a diagnosis can often be made within the first months of life. About 43% of CP cases are diagnosed within this time frame; about 70% are diagnosed by the end of their first year. More mildly affected children may not have a confirmed diagnosis until as late as age 3 or 4.
CEREBRAL PALSY TREATMENT
Cerebral palsy can’t be cured, but treatment will often improve a child’s capabilities. In general, the earlier treatment begins the better chance children have of overcoming developmental disabilities or learning new ways to accomplish the tasks that challenge them. Treatment may include physical and occupational therapy, speech therapy, drugs to control seizures, relax muscle spasms, and alleviate pain; surgery to correct anatomical abnormalities or release tight muscles; braces and other orthotic devices; wheelchairs and rolling walkers; and communication aids such as computers with attached voice synthesizers.