Cerebral palsy (CP) (also cerebral pares) is an umbrella term encompassing a group of non-progressive, non-contagious motor conditions that cause physical disability in human development, chiefly in the various areas of body movement.
Cerebral refers to the cerebrum, which is the affected area of the brain (although the disorder most likely involves connections between the cortex and other parts of the brain such as the cerebellum), and palsy refers to disorder of movement. CP is caused by damage to the motor control centers of the developing brain and can occur during pregnancy (about 75 percent), during childbirth (about 5 percent) or after birth (about 15 percent) up to about age three. Further research is needed on adults with CP as the current literature is highly focused on the pediatric patient.
Cerebral palsy describes a group of permanent disorders of the development of movement and posture, causing activity limitation, that are attributed to nonprogressive disturbances that occurred in the developing fetal or infant brain. The motor disorders of cerebral palsy are often accompanied by disturbances of sensation, perception, cognition, communication, and behaviour, by epilepsy, and by secondary musculoskeletal problems.
Of the many types and subtypes of CP, none has any known "cure". Usually, medical intervention is limited to the treatment and prevention of complications arising from CP's effects.
A 2003 study put the economic cost for people with CP in the US at $921,000 per individual, including lost income.
In another study, the incidence in six countries surveyed was 2.12–2.45 per 1,000 live births, indicating a slight rise in recent years. Improvements in neonatal nursing have helped reduce the number of babies who develop cerebral palsy, but the survival of babies with very low birth weights has increased, and these babies are more likely to have cerebral palsy.
All types of CP are characterized by abnormal muscle tone (i.e. slouching over while sitting), reflexes, or motor development and coordination. There can be joint and bone deformities and contractures (permanently fixed, tight muscles and joints). The classical symptoms are spasticities, spasms, other involuntary movements (e.g. facial gestures), unsteady gait, problems with balance, and/or soft tissue findings consisting largely of decreased muscle mass. Scissor walking (where the knees come in and cross) and toe walking (which can contribute to a gait reminiscent of a marionette) are common among people with CP who are able to walk, but taken on the whole, CP symptomatology is very diverse. The effects of cerebral palsy fall on a continuum of motor dysfunction which may range from slight clumsiness at the mild end of the spectrum to impairments so severe that they render coordinated movement virtually impossible at the other end the spectrum.
Babies born with severe CP often have an irregular posture; their bodies may be either very floppy or very stiff. Birth defects, such as spinal curvature, a small jawbone, or a small head sometimes occur along with CP. Symptoms may appear or change as a child gets older. Some babies born with CP do not show obvious signs right away. Classically, CP becomes evident when the baby reaches the developmental stage at 6/12 to 9/12 months and is starting to mobilise, where preferential use of limbs, asymmetry or gross motor developmental delay is seen.
Secondary conditions can include seizures, epilepsy, apraxia, dysarthria or other communication disorders, eating problems, sensory impairments, mental retardation, learning disabilities, and/or behavioral disorders.
Speech and language disorders are common in people with Cerebral Palsy. The incidence of dysarthria is estimated to range from 31% to 88%. Speech problems are associated with poor respiratory control, laryngeal and velopharyngeal dysfunction as well as oral articulation disorders that are due to restricted movement in the oral-facial muscles. There are three major types of dysarthria in cerebral palsy: spastic, dyskinetic (athetosis) and ataxic. Speech impairments in spastic dysarthria involves four major abnormalities of voluntary movement: spasticity, weakness, limited range of motion and slowness of movement. Speech mechanism impairment in athetosis involves a disorder in the regulation of breathing patterns, laryngeal dysfunction (monopitch, low, weak and breathy voice quality). It is also associated with articulatory dysfunction (large range of jaw movements), inappropriate positioning of the tongue, instability of velar elevation. Athetoid dysarthria is caused by disruption of the internal sensorimotor feedback system for appropriate motor commands, which leads to the generation of faulty movements that are perceived by others as involuntary. Ataxic dysarthria is uncommon in cerebral palsy. The speech characteristics are: imprecise consonants, irregular articulatory breakdown, distorted vowels, excess and equal stress, prolonged phonemes, slow rate, monopitch, monoloudness and harsh voice. Overall language delay is associated with problems of mental retardation, hearing impairment and learned helplessness. Children with cerebral palsy are at risk of learned helplessness and becoming passive communicators, initiating little communication. Early intervention with this clientele often targets situations in which children communicate with others, so that they learn that they can control people and objects in their environment through this communication, including making choices, decisions and mistakes.
While in certain cases there is no identifiable cause, other etiologies include problems in intrauterine development (e.g. exposure to radiation, infection), asphyxia before birth, hypoxia of the brain, and birth trauma during labor and delivery, and complications in the perinatal period or during childhood. CP is also more common in multiple births.
Studies at the University of Liverpool have led to the hypothesis that many cases of cerebral palsy, and other conditions that an infant has at birth, are caused by the death in very early pregnancy of an identical twin. This may occur when twins have a joint circulation through sharing the same placenta. Not all identical twins share the same blood supply (monochorionic twins), but if they do, the suggestion is that perturbations in blood flow between them can cause the death of one and damage to the development of the surviving fetus. It is common knowledge amongst obstetricians and midwives that a small dead fetus (fetus papyraceus) may sometimes be found attached to a placenta following birth. In the past, this has not been considered important and knowledge of the so called ‘vanishing twin’ has been suppressed to avoid triggering feelings of loss, grief, or guilt in mothers and especially the surviving twin. The pathological consequences depend on the severity and the stage of development of the fetus when the imbalances in blood flow between the fetuses occur. It has been proposed that such pathology could account, not just for cerebral palsy, but for developmental abnormalities of the eye, heart, and gut, and other specific brain abnormalities such as neuronal migration disorders e.g. lissencephaly and holoprosencephaly.
Between 40% and 50% of all children who develop cerebral palsy were born prematurely. Premature infants are vulnerable, in part because their organs are not fully developed, increasing the risk of hypoxic injury to the brain that may manifest as CP. A problem in interpreting this is the difficulty in differentiating between CP caused by damage to the brain that results from inadequate oxygenation and CP that arises from prenatal brain damage that then precipitates premature delivery.
Recent research has demonstrated that intrapartum asphyxia is not the most important cause, probably accounting for no more than 10 percent of all cases; rather, infections in the mother, even infections that are not easily detected, may triple the risk of the child developing the disorder, mainly as the result of the toxicity to the fetal brain of cytokines that are produced as part of the inflammatory response. Low birthweight is a risk factor for CP—and premature infants usually have low birth weights, less than 2.0 kg, but full-term infants can also have low birth weights. Multiple-birth infants are also more likely than single-birth infants to be born early or with a low birth weight.
After birth, other causes include toxins, severe jaundice, lead poisoning, physical brain injury, shaken baby syndrome, incidents involving hypoxia to the brain (such as near drowning), and encephalitis or meningitis. The three most common causes of asphyxia in the young child are: choking on foreign objects such as toys and pieces of food, poisoning, and near drowning.
Some structural brain anomalies such as lissencephaly may present with the clinical features of CP, although whether that could be considered CP is a matter of opinion (some people say CP must be due to brain damage, whereas people with these anomalies didn't have a normal brain). Often this goes along with rare chromosome disorders and CP is not genetic or hereditary.
CP is not a progressive disorder (meaning the brain damage neither improves nor worsens), but the symptoms can become more severe over time due to subdural damage. A person with the disorder may improve somewhat during childhood if he or she receives extensive care from specialists, but once bones and musculature become more established, orthopedic surgery may be required for fundamental improvement. People who have CP tend to develop arthritis at a younger age than normal because of the pressure placed on joints by excessively toned and stiff muscles.
The full intellectual potential of a child born with CP will often not be known until the child starts school. People with CP are more likely to have some type of learning disability, but this is not related to a person's intellect or IQ level. Intellectual level among people with CP varies from genius to mentally retarded, as it does in the general population, and experts have stated that it is important to not underestimate a person with CP's capabilities and to give them every opportunity to learn.
The ability to live independently with CP varies widely depending on the severity of each case. Some individuals with CP will require personal assistant services for all activities of daily living. Others can lead semi-independent lives, needing support only for certain activities. Still others can live in complete independence. The need for personal assistance often changes with increasing age and associated functional decline. However, in most cases persons with CP can expect to have a normal life expectancy; survival has been shown to be associated with the ability to ambulate, roll, and self-feed. As the condition does not directly affect reproductive function, some persons with CP have children and parent successfully.
According to OMIM, only 2% of cases of CP are inherited (with glutamate decarboxylase-1 as one known enzyme involved.) There is no evidence of an increased chance of a person with CP having a child with CP.
There is no cure for CP, but various forms of therapy can help a person with the disorder to function and live more effectively. 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. The earliest proven intervention occurs during the infant's recovery in the neonatal intensive care unit (NICU).
Treatment may include one or more of the following:
- physical therapy
- occupational therapy
- speech therapy
- drugs to control seizures and alleviate pain, or relax muscle spasms (e.g. benzodiazepienes, baclofen and intrathecal phenol/baclofen)
- hyperbaric oxygen
- the use of Botox to relax contracting muscles
- surgery to correct anatomical abnormalities or release tight muscles
- braces and other orthotic devices
- rolling walkers
- communication aids such as computers with attached voice synthesizers.
For instance, the use of a standing frame can help reduce spasticity and improve range of motion for people with CP who use wheelchairs. Nevertheless, there is only some benefit from therapy.
Treatment is usually symptomatic and focuses on helping the person to develop as many motor skills as possible or to learn how to compensate for the lack of them. Non-speaking people with CP are often successful availing themselves of augmentative and alternative communication systems such as Blissymbols.
Early Nutritional Support In one cohort study of 490 premature infants discharged from the NICU, the rate of growth during hospital stay was related to neurological function at 18 and 22 months of age. The study found a significant decrease in the incidence of cerebral palsy in the group of premature infants with the highest growth velocity. This study suggests that adequate nutrition and growth play a protective role in the development of cerebral palsy.
Physical therapy (PT) programs are designed to encourage the patient to build a strength base for improved gait and volitional movement, together with stretching programs to limit contractures. Many experts believe that life-long physical therapy is crucial to maintain muscle tone, bone structure, and prevent dislocation of the joints.
Occupational therapy helps adults and children maximise their function, adapt to their limitations and live as independently as possible.
Orthotic devices such as ankle-foot orthoses (AFOs) are often prescribed to minimise gait irregularities. AFOs have been found to improve several measures of ambulation, including reducing energy expenditure and increasing speed and stride length.
Speech therapy helps control the muscles of the mouth and jaw, and helps improve communication. Just as CP can affect the way a person moves their arms and legs, it can also affect the way they move their mouth, face and head. This can make it hard for the person to breathe; talk clearly; and bite, chew and swallow food. Speech therapy often starts before a child begins school and continues throughout the school years.
Hyperbaric oxygen therapy (HBOT), in which pressurized oxygen is inhaled inside a hyperbaric chamber, has been used to treat CP under the theory that improving oxygen availability to damaged brain cells can reactivate some of them to function normally. Its use to treat CP is controversial. A 2007 systematic review concluded that the effect of HBOT on CP is not significantly different from that of pressurized room air, and that some children undergoing HBOT will experience adverse events such as seizures and the need for ear pressure equalization tubes; due to poor quality of data assessment the review also concluded that estimates of the prevalence of adverse events are uncertain.
Nutritional counseling may help when dietary needs are not met because of problems with eating certain foods.
Both massage therapy and hatha yoga are designed to help relax tense muscles, strengthen muscles, and keep joints flexible. Hatha yoga breathing exercises are sometimes used to try to prevent lung infections. More research is needed to determine the health benefits of these therapies for people with CP.
Surgery for people with CP usually involves one or a combination of:
- Loosening tight muscles and releasing fixed joints, most often performed on the hips, knees, hamstrings, and ankles. In rare cases, this surgery may be used for people with stiffness of their elbows, wrists, hands, and fingers.
- The insertion of a Baclofen Pump usually during the stages while a patient is a young adult. This is usually placed in the left abdomen. It is a pump that is connected to the spinal cord, whereby it sends bits of Baclofen alleviating the continuous muscle flexion. Baclofen is a muscle relaxant and is often given PO to patients to help counter the effects of spasticity.
- Straightening abnormal twists of the leg bones, i.e. femur (termed femoral anteversion or antetorsion) and tibia (tibial torsion). This is a secondary complication caused by the spastic muscles generating abnormal forces on the bones, and often results in intoeing (pigeon-toed gait). The surgery is called derotation osteotomy, in which the bone is broken (cut) and then set in the correct alignment.
- Cutting nerves on the limbs most affected by movements and spasms. This procedure, called a rhizotomy, "rhizo" meaning root and "tomy" meaning "a cutting of" from the Greek suffix 'tomia' reduces spasms and allows more flexibility and control of the affected limbs and joints.
- Botulinum Toxin A (Botox) injections into muscles that are either spastic or have contractures, the aim being to relieve the disability and pain produced by the inappropriately contracting muscle.
- A new study has found that cooling the bodies and blood of high-risk full-term babies shortly after birth may significantly reduce disability or death.
Cord Blood Therapy: There are no published randomized controlled trials or meta-analysis of this treatment modality in cerebral palsy. In March 2008 a boy diagnosed with cerebral palsy appeared on the Today Show with his family. The parents noted that he could not walk on his own and appeared to be "swallowing his tongue" at times. He was eventually diagnosed with cerebral palsy and could only walk with the aid of a walker for a short time. Earlier that year he participated in a clinical trial involving his own cord blood that his parents had saved when he was born. His parents reported that within 5 days after the procedure he was walking on his own and talking, something his mother said he was not capable of on his own and it was doubtful he would ever be able to do on his own. They also reported that the doctors also told them that if his rate of progress continues uninterrupted until he is 7 he will be pronounced cured.
Conductive education (CE) was developed in Hungary from 1945 based on the work of András Pető. It is a unified system of rehabilitation for people with neurological disorders including cerebral palsy, Parkinson's disease and multiple sclerosis, amongst other conditions. It is theorised to improve mobility, self-esteem, stamina and independence as well as daily living skills and social skills. The conductor is the professional who delivers CE in partnership with parents and children. Skills learned during CE should be applied to everyday life and can help to develop age-appropriate cognitive, social and emotional skills. It is available at specialized centers.
Biofeedback is an alternative therapy in which people with CP learn how to control their affected muscles. Some people learn ways to reduce muscle tension with this technique. Biofeedback does not help everyone with CP.
Neuro-cognitive therapy. It is based upon two proven principles. Neural Plasticity. The brain is capable of altering its own structure and functioning to meet the demands of any particular environment. Consequently if the child is provided with an appropriate neurological environment, he will have the best chance of making progress. Learning can lead to development. As early as the early 1900s, this was being proven by a psychologist named Lev Vygotsky. He proposed that children's learning is a social activity, which is achieved by interaction with more skilled members of society. There are many studies, which provide evidence for this claim. there are however, as yet no controlled studies on neuro-cognitive therapy.
Patterning is a controversial form of alternative therapy for people with CP. The method is promoted by The Institutes for the Achievement of Human Potential (IAHP), a Philadelphia nonprofit, but has been criticized by the American Academy of Pediatrics. The IAHP's methods have been endorsed by Linus Pauling, as well as some parents of children treated with their methods.