Cerebral Palsy: Medical Aspects
Section snippets
Definition
The definition of cerebral palsy has evolved over the years, reflecting changing understanding of the causes and consequences of this disorder. A recent definition, put forward by the American Academy for Cerebral Palsy and Developmental Medicine, is:
Cerebral Palsy describes a group of disorders of the development of movement and posture, causing activity limitations, that are attributed to non-progressive disturbances that occurred in the developing fetal or infant brain. The motor disorders
Incidence
The incidence of cerebral palsy has remained virtually unchanged over the past 40 years at approximately 2.5 per 1000 live births.3 This represents a great disappointment to those who anticipated that advances in perinatal care would eliminate many cases of cerebral palsy, but a relief to those that feared a drastic increase in numbers due to improved survival of critically ill newborns. This is best understood in the context of our current understanding that the etiology of most cases of
Etiology
The etiology of cerebral palsy can be thought of using the four P's: prenatal, perinatal, postnatal, and prematurity. Common prenatal, perinatal, and postnatal causes of cerebral palsy include:
Prenatal
Brain malformations
In utero stroke
Congenital cytomegalovirus infection
Perinatal
Hypoxic ischemic encephalopathy
Viral encephalitis
Meningitis
Postnatal
Accidental head trauma
Anoxic insult
Child abuse
Although physicians and parents have traditionally thought of hypoxic or ischemic white matter damage as
Diagnosis
Despite advances in technology, cerebral palsy remains a clinical diagnosis, and represents a continuing role for the “art” of medicine. The essential findings include:
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Delayed motor milestones
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Abnormal muscle tone
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Hyperreflexia
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Absence of regression or evidence of a more specific diagnosis
These clinical findings should be present to the degree that the child appears unlikely to “outgrow” these findings. The potential to “outgrow” the manifestations of cerebral palsy is best recognized in the
Classification
The broad and inclusive nature of the term cerebral palsy limits it usefulness in both clinical and research settings: How much does a child with a localized motor deficit due to a small prenatal stroke have in common with a child who had a global brain insult due to herpes encephalitis? This has been traditionally addressed using a classification system combining the predominant type of motor abnormality with the distribution of this abnormality (Box 1). This classification system has recently
Prognosis
Most parents ask: “Will my child walk?” An often unspoken question is: “Will my child be able to have a long life?” The majority of children with cerebral palsy do walk. Historically, the outlook for walking in a particular child was based on either their subtype of cerebral palsy or their age of sitting. Children with hemiplegic and diplegic cerebral palsy usually walk, while those with quadriplegia rarely do, and those with dyskinetic cerebral palsy have an intermediate chance of ambulation.
Management
For optimal care, the child with cerebral palsy must not be viewed in isolation, but rather considered in the context of his or her family and community. Family-centered care is considered the optimal model of care for all children, but is especially important for children with special needs.22 The essence of family-centered care is the recognition that, while we as medical professionals bring knowledge, training, and experience to the team, parents bring specific knowledge about their child
Seizures
Approximately 30% of persons with cerebral palsy have a seizure disorder.30 Just like seizures in the general population, seizures in persons with cerebral palsy may come on at any age and be of any type. In other words, there is nothing “unique” about seizures in children with cerebral palsy. Choice of anticonvulsants, when required, is guided as usual by seizure type and side effect profile. Also like other children, a child with cerebral palsy may be able to be tried off such medicines once
Cognition/learning
Roughly half of individuals with cerebral palsy have associated cognitive impairment, with others having overall cognitive skills in the normal range but with specific deficits in learning or attention that could be classified as learning disabilities or attention-deficit/hyperactivity disorder.30 The risk of associated cognitive or learning difficulties varies somewhat with the type of cerebral palsy, with those with quadriplegic cerebral palsy having the highest risk of cognitive impairment
Nutrition and growth
Children with cerebral palsy face multiple challenges to normal growth, and are more likely to be underweight and short compared with peers.34 Most evidence in regards to stature,35 however, points to the short stature as a consequence of being chronically underweight. Even adequate assessment of growth status can be a challenge in this population. Medical offices may lack scales for older children who cannot stand, and length measures may be difficult to reliably obtain in a child with joint
Swallowing
Persons with cerebral palsy are at increased risk for dysphagia, which can affect their health in several ways. Dysphagia with aspiration may result in or contribute to recurrent pulmonary infections or reactive airway disease. It can limit food choices and compromise the efficiency of intake, contributing to impaired nutrition. However, just as in the discussion of gastroesophageal reflux above, dysphagia may not always present as clinicians might expect. When documented to aspirate, most
Gastrointestinal
Just as control of the muscles of the limbs and trunk are affected in cerebral palsy, so is the smooth muscle of the gastrointestinal tract. Persons with cerebral palsy have a high incidence of gastroesophageal reflux and constipation, and may have altered gut motility as well, resulting in delayed gastric emptying and intestinal dysmotility.45 Disorders here may have an impact on many aspects of a child's life. Both gastroesophageal reflux and constipation can impair nutritional intake and be
Respiratory
Respiratory compromise in children with cerebral palsy is a major source of morbidity and mortality, especially among those with severe motor involvement. Cerebral palsy is associated with an increased risk of upper airway obstruction, which can cause chronic obstructive sleep apnea, as well as acute airway obstruction, especially when illness or sedation compound underlying airway issues.53 Snoring in association with apneic pauses or gasping respirations is a clear indication for
Orthopedic
Orthopedic surgeons experienced in the care of children with cerebral palsy are integral members of the treatment team for all but those most mildly affected. They can monitor for the secondary musculoskeletal complications of cerebral palsy, which include contractures, joint dislocations (especially at the hips), and bony deformities, such as scoliosis. Orthopedic surgeons can also suggest interventions to prevent such complications. Through prescription of therapy and bracing, they can direct
Abnormal tone
Spasticity affects most people with cerebral palsy, and a significant minority have dystonia, either in addition to or instead of the spasticity. Despite the clear difference in definitions, dystonia and spasticity are commonly confused in practice. Developing the skills to differentiate the two is important for patient care, as different treatment approaches are often needed. Spasticity is defined as a velocity-dependent increase in tone. Dystonia involves involuntary muscle contractions that
Vision
Individuals with cerebral palsy have a high incidence of eye disorders, which range from refractive errors and strabismus to visual impairment.74 There is some relationship to the etiology of the child's cerebral palsy, as prematurity is associated with retinal abnormalities that may affect vision75 and also cause a high incidence of severe myopia.76 Those with a severe global central nervous system insult or disproportionate occipital involvement are at more risk of cortical visual impairment,
Hearing
The incidence of hearing impairment in persons with cerebral palsy is estimated to be 10% to 15%.80 Just as in the case of vision, preterm infants are at increased risk, as are those who suffered a hypoxic or infectious insult. Former premature infants, as well as infants treated with extracorporeal membrane oxygenations81 and those with intrauterine cytomegalovirus infections82 may experience late-onset or progressive hearing loss, and thus require periodic hearing assessment over the first
Urologic
A poorly defined subset of individuals with cerebral palsy may experience voiding dysfunction.83 This possibility should be considered in those with recurrent urinary tract infections, unexplained irritability, or failure to achieve continence when otherwise expected based on the child's level of cognitive and motor functions. Studies have indicated that, on average, children with cerebral palsy achieve continence later than their peers,84 but the data were not controlled for cognitive level.
Dental
Persons with cerebral palsy are high risk for dental issues.85 These include malocclusion due to the abnormal forces in the oromotor musculature.86 Some children with cerebral palsy have a hyperactive gag reflex or oral aversion, which makes dental hygiene difficult. The child's positioning needs may be difficult to accommodate in the usual dental office, and the individual may have difficulty cooperating with dental procedures because of motor or cognitive issues.87 Finally, dental care
Sialorrhea
Individuals with oromotor impairment may experience drooling past the age considered socially acceptable, or many do so to a degree that interferes with activities. Complications of chronic drooling may include odor, chapping, and, rarely, pulmonary compromise. Like many other issues, a spectrum of interventions exists from least to most invasive, with treatment decisions guided more by the degree to which sialorrhea is interfering with the individual's life than by the amount or frequency of
Pain
Pain is a common problem for individuals with cerebral palsy, with more than half of adults95 and children96 with cerebral palsy reporting pain as an ongoing health concern. Common sources are musculoskeletal and gastrointestinal. Particularly challenging is the nonverbal child with severe cerebral palsy who is excessively irritable or who cries with discomfort. Parents are sometimes desperate to find someone who will take responsibility for working through the problem as opposed to ruling out
Sleep
Children with cerebral palsy are prone to sleep problems, with an incidence recently reported to be 23%.97 These difficulties may include difficulty falling asleep, frequent night awakening, and a sleep schedule that does not fit the needs of school or family. For any given child, there are potential behavioral, neurologic, and physical causes. Some parents of children with special needs may have difficulty with the limit setting that is necessary for children to develop good sleep habits, such
Transition
The vast majority of individuals with cerebral palsy live into adulthood and thus need to make the transition to adult medical care. Numerous barriers to this transition have been identified,99 including insufficient knowledge and training in childhood-onset disabilities among adult health care providers, as well as funding issues. The American Academy of Family Medicine, the American College of Physicians, and the American Academy of Pediatrics100 have agreed on steps to ease the transition of
Summary
Making the diagnosis of cerebral palsy is only the beginning. The role of the pediatric health care provider is also to help families manage the ongoing health issues that may arise, and to give the families the confidence they are doing all that they can and should do to help their child reach his or her potential.
Acknowledgments
The author wishes to thank her colleagues for their constructive comments and Terri Shoemaker for assistance with the references.
References (100)
- et al.
The descriptive epidemiology of cerebral palsy
Clin Perinatol
(2006) Cerebral palsy in term infants—birth or before birth?
J Pediatr
(2001)- et al.
Neuroimaging abnormalities in infants with congenital hemiparesis
Pediatr Neurol
(2006) Misdiagnoses in children with dopa-responsive dystonia
Pediatr Neurol
(2004)- et al.
Neuromotor spectrum of periventricul leukomalacia in children born at term
Pediatr Neurol
(2000) - et al.
Prevalence of feeding problems and oral motor dysfunction in children with cerebral palsy: a community survey
J Pediatr
(1996) - et al.
Gastric emptying in children with cerebral palsy and gastroesophageal reflux
Pediatr Neurol
(2004) - et al.
Gastrointestinal manifestations in children with cerebral palsy
Brain Dev
(1999) - et al.
Extraesophageal associations of gastroesophageal reflux disease in children without neurological defects
Gastroenterology
(2001) - et al.
Colonic transit time and constipation in children with spastic cerebral palsy
Arch Phys Med Rehabil
(2004)