Roy is a 13 month old male who has been followed in the Pediatric outpatient clinic. He was born at term by normal vaginal delivery without complications and his birth weight was 3300g. His mother did not have any problems during the pregnancy. At 6 months of age, you noticed his head control was poor. Currently, he calls everyone "mama" and follows one-step commands. He is able to drink from a cup. He is able to roll over from his stomach to his back but he is not able to sit or stand. His height and weight are both between the 25-50th percentiles and his head circumference is within 2 standard deviations of the mean. Some primitive reflexes such as the Asymmetric Tonic Neck Reflex (ATNR) persist and he has increased muscle tone, especially in his legs. His deep tendon reflexes are exaggerated.
Cerebral palsy (CP) is defined as a non-progressive, but often clinically changing motor impairment due to an abnormality of the developing brain. It is a symptom complex or a descriptive term rather than a specific disease. Intellectual, sensory, and/or behavioral problems may also exist although the primary abnormality must be a motor deficit. The prevalence is estimated at about 2 per 1000 early school aged children (1).
In more than 50% of the children who have CP, an etiology may not be evident (1). The insult to the brain may occur prenatally (e.g., congenital malformation, intrauterine infections, teratogens), perinatally (e.g., birth trauma, anoxia), or postnatally (e.g., infections, accidental or non-accidental trauma, intracranial hemorrhage). The majority of the cases are not caused by hypoxic ischemic incidents occurring perinatally as it was believed until recently. 70-80% cases are prenatal in origin (3). Infants who weigh less than 1500g at birth have a 10% to 20% risk of developing CP (2). Although prematurity is the most common known antecedent of CP, the majority of children who develop CP are born at term.
CP is often classified according to the predominant type of motor impairment: spastic, dyskinetic, ataxic, or mixed. Spastic CP is the most common type and affects 70-80% of individuals with CP. It is characterized by a generalized increase in muscle tone. CP can be further classified based on which limbs are involved, the suspected etiology or functional capacities. For example, in spastic diplegia, the lower extremities are more involved than the upper extremities. In hemiplegia, one side of the body is more involved. All the extremities and often trunk and oral motor function are also affected in spastic quadriplegia.
Choreoathetoid CP is a subtype of dyskinetic CP. Athetosis are slow writhing involuntary movements and involves distal limbs. Choreiform movements are asymmetric, uncoordinated, involuntary muscle contractions. These movements are more prominent under stress and their intensity may change. It may not be apparent until about 12 to 18 months of age when a toddler starts to show athetoid or dystonic posturing on voluntary movements. One known cause of this form of CP is encephalopathy associated with very high bilirubin levels during the neonatal period.
Ataxic CP is characterized by cerebellar dysfunction. This is the least common type with a frequency of 1% among individuals with CP. Mixed CP involves both symptoms of upper motor neuron and extrapyramidal symptoms. For example, a child who has spastic quadriplegia may also have choreoathetoid movements.
The diagnosis of CP is essentially clinical and depends on knowledge of normal development and its variation. While no factors or combination of factors is an absolute predictor of CP, certain situations warrant closer monitoring. It is also important to remember that the neurological picture may change as the child grows older and the CNS matures. It is often difficult to diagnose children with CP before 6 months of age.
During infancy, feeding difficulty is an important sign. A child may continue to need gavage (tube) feedings. He or she may be difficult to feed, or require an excessive amount of time for feeding. A child may have failure to thrive or a poor rate of head growth due to a serious insult to the brain. Constipation is another symptom among infants with CP. He/she may be quiet and very easy, or irritable during infancy. The child may show a premature handedness preference during the first 18 months of life. This can be an early sign of hemiplegia.
There are several useful parameters for the assessment of neuromotor function.
A) Muscle function: Muscle tone and strength should be examined. By simple observation, you may be able to see poor head control, scissoring of the lower extremities, or flexor posturing of upper extremities.
B) Patterns of movement should be assessed. There are three patterns of movements: 1) Normal movements, 2) Abnormal movements which are never seen in normally developing children (e.g., restricted movements in children with spastic diplegia or hemiplegia, or involuntary movements seen in children with athetoid CP), 3) Atypical movements which may be seen in normally developing children (e.g., bouncing along the floor while supine, or log-rolling as methods of mobility).
C) Structure or alignment of the body. A child with spastic CP may have dislocation of the hip due to adductor and abductor muscle tone imbalance and resultant poor joint development. Children with spastic CP also have the tendency for plantar flexion of the feet. Scoliosis can be a problem for all children with CP.
D) Reflexes should be assessed. Physicians are generally very familiar with the deep tendon reflexes. Of equal significance are so-called developmental reflexes. Children with CP may have persistent primitive reflexes such as the Moro reflex and the asymmetric tonic neck reflex (ATNR). Also, children with CP may present with delayed emergence of righting reactions (natural tendency to position the body/head upright) and protective/equilibrium responses (e.g., parachute reflex) as signs of delayed maturation or CNS injury.
E) Gross motor skills are usually affected but other developmental milestones should be also assessed to determine if delays are more global.
Many co-existing conditions are frequently seen in children with CP. These may include sensory impairments, seizures, cognitive impairment, orthopedic problems, impaired speech and language, feeding issues, dental problems, skin breakdown and respiratory infections. Because CP is the result of an insult to the developing brain, some of these problems may not be treatable or they may only partially respond to medical/surgical treatment. The treatment plans and programs must be individualized and modified over time as the child grows.
Children with CP have a high incidence of visual impairments (4,5). They may have refractive errors, visual fields defects, or cortical blindness. Strabismus is very common and may lead to the development of amblyopia. There is also an increased incidence of sensorineural and conductive type hearing impairment. Hearing impairments can further delay speech and language development of children with CP.
25-50% of children with CP may also experience seizures (4,5). Seizures are most commonly seen among the children with spastic quadriplegia and hemiplegia. Generalized tonic-clonic and partial seizures are the common types. Approximately half of the children with CP have mental retardation. Although children with more severe motor involvement tend to have mental retardation more frequently, this is not always the case. Among children with normal intelligence, there is a higher incidence of learning disabilities. Feeding difficulties (e.g., with sucking, chewing, and/or swallowing) are common among children with CP as a result of impairment of oral motor muscle function. This may also cause problems with speech articulation. Drooling and gastroesophageal reflux may also occur. Aspiration can cause pneumonia which is the leading cause of death in children with CP.
Because of the difficulties in motor control, assistance is needed to maintain good posture and alignment and good range of motion of the joints. Subluxation or dislocation of the hip are common in children with CP. The incidence is higher among children with spastic quadriplegia. Dislocated hips can develop arthritis and severe pain. Poor posture or positioning can result in scoliosis due to the unequal muscle tension. Spasticity and limited muscle use may lead to contractures. The interventions used to treat these conditions include physical therapy, orthopedic surgery, muscle tone management (e.g., intrathecal Baclofen infusion), and orthoses (e.g., ankle-foot orthosis, body shell).
The life expectancy of children with CP depends on the type and the severity of the condition. Although the projected life span of children with CP is less than that of the general population due to complications of motor dysfunction, the majority of affected children will survive well into adulthood if given appropriate medical attention.
The prognosis regarding ambulation is also dependent on the type and the severity of the motor dysfunction. Overall, children with hemiparesis will walk by 18 months to 36 months. With or without assistive devices, 80-90% of children with diplegia, 70% of children with dyskinesia and 50% of children with quadriplegia may achieve some degree of ambulation (1). Ambulation may be predicted based on the achievement of motor milestones. For example, there is a good prognosis for attaining some ambulation if a child is able to sit independently by 24 months.
Because of multisystem involvement and various psychosocial and medical needs, no one discipline can assess and manage all aspects of the child with CP alone. It is important to be interdisciplinary to have a successful management program. The child's physician has to be familiar with community resources such as early intervention programs and support groups. It is important for the primary care physician to communicate with the therapists, specialists, and school personnel. The physician needs to advocate for the necessary services for the child and his/her family. Primary care physicians should be aware of the different problems and needs that the children experience as they get older and help them transition from the toddler to school age to adulthood as smoothly as possible. The goal for the treatment program is to maximize function and optimize development to help them participate in as many activities as possible in multiple social settings.
1. Cerebral Palsy may have changing clinical features in: (select one)
. . . . . a. The brain abnormality.
. . . . . b. Effects on the motor system.
. . . . . c. That seizures are usually not treatable after a few years.
. . . . . d. Subtypes - first a person has the choreoathetoid type, then the spastic type, and then becomes quadriplegic.
. . . . . e. Decrease in IQ over time.
2. Currently, most cases of cerebral palsy with a known etiology are thought to be
. . . . . a. Prenatal in origin.
. . . . . b. Perinatal in origin.
. . . . . c. Postnatal in origin.
3. What is the most common type of cerebral palsy?
. . . . . a. Spastic
. . . . . b. Choreoathetoid
. . . . . c. Ataxic
. . . . . d. Mixed
. . . . . e. All are equally common
4. Which of the following is NOT a worrisome sign that may indicate cerebral palsy?
. . . . . a. Poor rate of head growth
. . . . . b. Hand preference at 6 months of age
. . . . . c. Scissoring of the legs
. . . . . d. Obesity
. . . . . e. High muscle tone
5. True/False: Because of the neuromotor dysfunction and associated conditions, children with cerebral palsy rarely live into adulthood.
6. True/False: Children with hemiplegia have a higher rate of ambulation than diplegia and quadriplegia
1. Taft LT. Cerebral palsy. Pediatr Rev 1995;16(11):411-418.
2. Kuban KCK, Leviton A. Cerebral Palsy. New Engl J Med 1994;330(3):188-195.
3. Miller F, Bachrach SJ. Cerebral Palsy: A Complete Guide for Caregiving. 1998, Baltimore: John Hopkins University Press.
4. Blackman JA. Cerebral Palsy. In: Wolraich ML (ed). Disorders of Development and Learning: A Practical Guide to Assessment and Management, 2nd edition. 1996, St. Louis: Mosby, pp. 186-212.
5. Swaiman KF, Russman BS. Cerebral Palsy. In: Swaiman KF, Ashwal S (eds). Pediatric Neurology: Principles & Practice, 3rd edition. 1999, St. Louis: Mosby, pp. 312-324.
6. United Cerebral Palsy Associations, Inc. (www.ucpa.org)
7. American Academy for Cerebral Palsy and Developmental Medicine (www.aacpdm.org)
Answers to the questions
1.b, 2.a, 3.a, 4.d, 5.false, 6.true