cerebral palsy - macpeds.com · cerebral palsy lawrence t.taft, md* tobeclassified ascerebral palsy...

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FOCUS QUESTIONS 1. In reaching a diagnosis, how would you differentiate among diplegic, hemiplegic, quadriplegic, and athetoid cerebra] palsy? 2. What are the most common causes of each of the four types of cere- bral palsy? 3. What risk factors are associated with cerebral palsy? 4. What disabilities are most likely to be associated with cerebral palsy, and how are they managed? *professor of Pediatrics, University of Medicine & Dentistmy of New Jersey, Robert Wood Johnson Medical School, New Brunswick, NJ. Pediatrics in Review Vol. 16 No. // November 1995 411 ARTICLE Cerebral Palsy Lawrence T. Taft, MD* To be classified as cerebral palsy (CP), there must be difficulty in neu- romotor control, a nonprogressive brain lesion, and an injury to the brain that occurred before it was fully mature. The term ‘cerebral palsy” should be used only if a static encephalopathy exists. If there is any question that a progressive central nervous system disorder exists, the term “cerebral palsy” should not be used diagnostically until the status of the lesion is clarified. Although the primary abnormality must be a motor deficit, often there are many associated symptoms of cerebral dysfunction present. Incidence and Prevalence The prevalence of CP has changed very little over the past 40 years, in spite of many technological advances that have decreased mortality in com- promised preterm and full-term in- fants. The prevalence rate has been estimated to be between 2 and 5 per 1000 live births. At 12 months of age, the prevalence rate was esti- mated to be 5.2 per 1000, but at 7 years of age, the rate was estimated to be 2 per 1000 live births. This indicates that many children who showed signs or experienced symp- toms suggesting a motor disorder did not have CP on follow-up. The past 3 decades have seen an increased survival rate of very small preterm infants, resulting in a change in the percentage rates of the differ- ent clinical types of motor disabilities among patients classified as having CP. Because preterm infants are sus- ceptible to developing a spastic diple- gia, this type of disability now is the most common. Of children whose CP is identified at 7 years of age, one third have a spastic diplegia. There is a definite correlation be- tween birthweight and/or gestational age and the incidence of CP. Etiology The insult to the brain may occur prenatally, perinatally, or postnatally. Until recently it was believed that hypoxic/ischemic incidents occurring pennatally caused the majority of CP cases. However, a collaborative pen- natal project started in 1960 that fol- lowed 454 000 pregnant women and the outcome of their offspring re- vealed that adverse prenatal factors may be the primary culprits. An ab- normal fetal brain on fetal environ- ment may make the infant more vul- nerable for being born prematurely or, if born full-term, may place him on hen at risk for cardiorespinatory problems in the neonatal period. In more than 50% of the patients who have CP, an etiology may not be evident, even after having obtained a comprehensive history for known high-risk factors and a genetic his- tory; having performed a complete physical and neurological examina- tions; and having evaluated meta- bolic, chromosomal, and neunoimag- ing studies. Although prematurity is the most common antecedent of CP, the majority of infants who develop this disorder have had full gestational terms. This paradox is explained by there being seven to ten times more full-term than preterm babies born. The lower the birthweight, the higher the incidence of CP. However, even for very low-birthweight infants (<1500 g), there is only a 15% to 20% risk of CP. Preterm infants who develop intraventricular hemorrhage, especially with extension of the hem- orrhage into the white matter, are at the greatest risk for developing CP. However, the best predictor of CP is the presence of echodensities in the peniventnicular white matter that de- velop into cysts. If the cysts are more than 3 mm in diameter, it has been estimated that there is a 90% to 95% chance of developing a spastic diple- gic CP. The Apgan score, whether in pre- term on full-term infants, has been a poor indicator of babies at risk for brain damage. For instance, with an Apgar score of 3 or less at 10 to IS minutes, the risk of developing CP varies from 10% to 15%. On the other hand, the majority of full-term infants who develop CP have normal Apgar scores. Table 1 lists the timing of pathoge- netic periods in CP. It is evident that a relatively high percentage of infants who have CP had no identifiable risk factors and that postnatal causes are infrequent. Certain types of insults have clini- cal pathologic correlations. For exam- pie, in preterm infants the germinal matrix is juxtaposed to the peniven- tniculan white matter. The germinal matrix of a preterm infant is suscepti- ble to bleeding because it has a low resistance to hypoxia and/or isch- emia. The immediate peniventnicular white matter contains the long-tract pyramidal fibers that descend to the spinal cord segments responsible for neuromotor control of the lower ex- tremities. More peripheral are the pyramidal fibers destined for the cer- vical spinal cord segments. Conse- quently, the pathology in preterm infants usually is limited to the long tracts that supply the lower extremi- ties, resulting in a spastic diplegia (eg, legs involved more than arms). Another clinical pathologic correla- tion is seen with bilirubin encepha- lopathy. Bilirubin is especially toxic to the neurons of the basal ganglia. Hyperbilirubinemia existing in an immature nervous system, if in toxic amounts, results in athetoid CP. Also, the auditory nuclei in the brain stem are especially susceptible to the toxic effects of bilirubin. Therefore, a high percentage of children who have athetoid CP have a neurosensory hearing loss.

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FOCUS QUESTIONS1. In reaching a diagnosis, how

would you differentiate among

diplegic, hemiplegic, quadriplegic,and athetoid cerebra] palsy?

2. What are the most common causesof each of the four types of cere-

bral palsy?3. What risk factors are associated

with cerebral palsy?

4. What disabilities are most likely to

be associated with cerebral palsy,

and how are they managed?

*professor of Pediatrics, University of

Medicine & Dentistmy of New Jersey, RobertWood Johnson Medical School, New

Brunswick, NJ.

Pediatrics in Review Vol. 16 No. / / November 1995 411

ARTICLE

Cerebral PalsyLawrence T. Taft, MD*

To be classified as cerebral palsy(CP), there must be difficulty in neu-romotor control, a nonprogressivebrain lesion, and an injury to thebrain that occurred before it wasfully mature. The term ‘ ‘cerebralpalsy” should be used only if a staticencephalopathy exists. If there is anyquestion that a progressive centralnervous system disorder exists, theterm “cerebral palsy” should not beused diagnostically until the status of

the lesion is clarified.Although the primary abnormality

must be a motor deficit, often thereare many associated symptoms ofcerebral dysfunction present.

Incidence and Prevalence

The prevalence of CP has changedvery little over the past 40 years, inspite of many technological advances

that have decreased mortality in com-promised preterm and full-term in-fants. The prevalence rate has been

estimated to be between 2 and 5 per1000 live births. At 12 months of

age, the prevalence rate was esti-mated to be 5.2 per 1000, but at7 years of age, the rate was estimatedto be 2 per 1000 live births. Thisindicates that many children whoshowed signs or experienced symp-toms suggesting a motor disorder didnot have CP on follow-up.

The past 3 decades have seen anincreased survival rate of very small

preterm infants, resulting in a changein the percentage rates of the differ-ent clinical types of motor disabilitiesamong patients classified as having

CP. Because preterm infants are sus-ceptible to developing a spastic diple-gia, this type of disability now is themost common. Of children whose CPis identified at 7 years of age, onethird have a spastic diplegia.

There is a definite correlation be-

tween birthweight and/or gestational

age and the incidence of CP.

Etiology

The insult to the brain may occurprenatally, perinatally, or postnatally.

Until recently it was believed thathypoxic/ischemic incidents occurringpennatally caused the majority of CPcases. However, a collaborative pen-natal project started in 1960 that fol-lowed 454 000 pregnant women andthe outcome of their offspring re-vealed that adverse prenatal factorsmay be the primary culprits. An ab-normal fetal brain on fetal environ-

ment may make the infant more vul-nerable for being born prematurelyor, if born full-term, may place him

on hen at risk for cardiorespinatoryproblems in the neonatal period.

In more than 50% of the patientswho have CP, an etiology may not be

evident, even after having obtained acomprehensive history for knownhigh-risk factors and a genetic his-

tory; having performed a completephysical and neurological examina-

tions; and having evaluated meta-bolic, chromosomal, and neunoimag-ing studies. Although prematurity is

the most common antecedent of CP,

the majority of infants who developthis disorder have had full gestationalterms. This paradox is explained bythere being seven to ten times more

full-term than preterm babies born.The lower the birthweight, the

higher the incidence of CP. However,even for very low-birthweight infants(<1500 g), there is only a 15% to20% risk of CP. Preterm infants whodevelop intraventricular hemorrhage,especially with extension of the hem-orrhage into the white matter, are atthe greatest risk for developing CP.

However, the best predictor of CP isthe presence of echodensities in thepeniventnicular white matter that de-velop into cysts. If the cysts are morethan 3 mm in diameter, it has beenestimated that there is a 90% to 95%

chance of developing a spastic diple-

gic CP.

The Apgan score, whether in pre-term on full-term infants, has been a

poor indicator of babies at risk forbrain damage. For instance, with anApgar score of 3 or less at 10 to ISminutes, the risk of developing CPvaries from 10% to 15%. On the

other hand, the majority of full-term

infants who develop CP have normalApgar scores.

Table 1 lists the timing of pathoge-

netic periods in CP. It is evident thata relatively high percentage of infantswho have CP had no identifiable riskfactors and that postnatal causes areinfrequent.

Certain types of insults have clini-cal pathologic correlations. For exam-pie, in preterm infants the germinalmatrix is juxtaposed to the peniven-tniculan white matter. The germinalmatrix of a preterm infant is suscepti-ble to bleeding because it has a low

resistance to hypoxia and/or isch-emia. The immediate peniventnicularwhite matter contains the long-tractpyramidal fibers that descend to thespinal cord segments responsible for

neuromotor control of the lower ex-tremities. More peripheral are thepyramidal fibers destined for the cer-vical spinal cord segments. Conse-

quently, the pathology in preterminfants usually is limited to the long

tracts that supply the lower extremi-ties, resulting in a spastic diplegia

(eg, legs involved more than arms).Another clinical pathologic correla-

tion is seen with bilirubin encepha-lopathy. Bilirubin is especially toxic

to the neurons of the basal ganglia.Hyperbilirubinemia existing in animmature nervous system, if in toxicamounts, results in athetoid CP. Also,the auditory nuclei in the brain stemare especially susceptible to the toxiceffects of bilirubin. Therefore, a highpercentage of children who have

athetoid CP have a neurosensoryhearing loss.

NEUROLOGYCerebral Palsy #{149}

TABLE 1. Timing of Pathogenetic Periods in Cerebral Palsy*

TERM BIRThS PRETERM BIRTHS

N=457(%) N=224(%)

Obvious prenatal cause or risk 24 6

factor

Combined prenatal and perinatal 20 23

factors

Purely peninatal factors 19 51

No identifiable risk factors 30 17

Obvious postnatal cause 8 2

*Adapfed from Hagberg B and Hagberg (3 (210, pp 116-134)

4/2 Pediatrics’ in Review Vol. /6 No. / / November 1995

Classification

Classification of the cerebral palsiesstill is based on the type of motor

disorder, not on etiology or pathol-ogy. Although the available neuro-imaging techniques may help in de-

fining the anatomic deficit better,they still will not reveal any pathol-ogy in the majority of children whohave CP. The clinical classification isbased on the extremities involved, the

type of tone abnormalities, and thecharacteristics of the involuntarymovements. One problem in using

the type of motor dysfunction forclinical classification is that the neu-rologic picture may change as theinfant grows older. Therefore, theexact type of motor deficit may notbe clarified until 2 to 3 years of age.

An added difficulty is that 20% to30% of infants who appear to fit thecriteria for the diagnosis of CP at1 year of age will not show any man-ifestations of a motor deficit by7 years of age. Pediatricians must becautious in prognosticating whetheran infant will or will not have CP orin offering a judgment as to futurecognitive abilities.

Clinical Characteristics

Table 2 offers a clinical classificationof cerebral palsy. Spastic diplegiaencompasses the largest number of

CP patients. In the past decade, thenumber of patients who have spasticdiplegia have, relatively speaking,increased in numbers, concomitant

with the increased survival rates ofpreterm infants.

Because the insults to the brain

that produce CP often result in dif-

fuse pathology, the mixed types ofCP are not uncommon. Those clini-cians who appraise movement disor-dens carefully find that more than10% are of the mixed variety. Priorto the use of immunoglobulins toprevent blood incompatibility from

developing in pregnant women, bil-irubin encephalopathy with resultingkernicterus and athetosis occurred ata higher percentage than shown inTable 2. Now the most commoncause of the athetoid-dystonic type ofCP is hypoxic-ischemic injury to thebasic ganglia.

Ataxic-spastic CP and spastic CPfrequently have similar antecedents.Hydrocephalus often is present inataxic-spastic disorders. Genetic fac-tors have been implicated in the pureataxic CP. Also, it is necessary to beaware that when ataxia is the primarymotor disorder, one should not imme-diately conclude that the diagnosis isCP. Ataxia is a relatively uncommontype of CP, but it is not uncommonas a manifestation of a progressive

neurometabolic encephalopathy. Thechild who has nonprogressive ataxicCP frequently is mentally retarded.

Many children who have insults totheir motor systems at birth will showtransient hypotonia that develops into

increased tone of the spastic or rigidtype. A few will remain hypotonicthroughout life. These children who

have “atonic CP” have severe motorand intellectual disabilities.

Clinical Approach toDiagnosis

Any infant whose motor developmenthas been delayed must be considered

suspect for having CP. Diagnosis isvery difficult before 6 months of age,

primarily because abnormalities in

tone or reflexes or involuntary move-

ments rarely manifest during early

infancy. The primary reason for thisis that much of the movement ob-served in infants younger than a few

months of age is of reflex origin and

not under voluntary motor cortical

control. It is only with maturation ofthe cortex that the clinical picture of

CP emerges more clearly. There of-ten is additional diagnostic uncer-

tainty after an acute peninatal insultto the brain. Tone and reflex abnor-

malities may be noted immediatelyand falsely indicate permanent dam-

age to the central nervous systemmotor system. However, the tone

and reflex changes may prove to betransient phenomena; after 2 to

12 months, these signs of CP

disappear.

Delay in achieving motor mile-

stones at an appropriate age is com-mon for children who are retarded

but who do not have CP. Adding to

the diagnostic dilemma is that manyof these children present with hypo-

tonia. One should be much more

highly suspicious of the presence ofCP if there is a motor delay but evi-

dence of normal cognitive develop-ment. However, that is not to say that

children who have CP cannot be re-

tarded; more than 50% of them are.When assessing a child who has a

motor delay, it is necessary to decidewhere the pathology exists anatomi-

cally: centrally (eg, brain) or peniph-erally (eg, spinal cord, anterior horn

cell, peripheral nerve, myoneuraljunction, or muscle). If the brain is

the site of the pathology. the child isconsidered to have CP.

It also is important to determine ifthe motor delay is a manifestation ofa progressive central nervous systemdisorder. Clues to a progressive dis-order are: I) regression; 2) normaldevelopment for a period of time,then a slowing; 3) consanguinity;

4) congenital skeletal anomalies suchas pes cavus or scoliosis; and 5) neu-rocutaneous stigmata. In certain pro-gressive diseases, the evidence ofregression may not occur until verylate in the course; at the early onsetof the disorder, only a delay inachievement of motor milestones

TABLE 2. Clinical Classification of Cerebral Palsy

TYPE FREQUENCY %

Spastic 70-80Hemiparesis (monoparesis)*Diplegia

Quadriparesis (double hemiplegia)

Dyskinetic 10-15

AthetoidDystonicChoreaBallismusTremor

Rigid 5

Ataxic

Mixed 10-15

*Dipfrgia is becoming the most common type of spastic CP as more preterm infants

survive.

Pediatrics in Review Vol. 16 No. / / November /995 413

NEUROLOGYCerebral Palsy

(and not regression) will be the pre-senting symptoms.

Spastic paraparesis, if associatedwith a peripheral sensory disturbance,is not a manifestation of CP, but in-dicates a transverse myelitis, an intra-or extrathecal mass lesion, or a neu-rodegenerative spinal cord disorder.

Primary lower motor neuron Ic-sions (anterior horn cell, peripheralnerve, myoneural junction, or mus-dc) are manifested by weakness, lowtone, and decreased-to-absent reflexes.There is no involuntary movement.

Early Signs

It is difficult to diagnose CP beforethe infant is 6 months of age. How-ever. a number of clues can raise theindex of suspicion. These so-calledhigh-risk findings can be assessedeasily during a routine well-child cx-

amination. Many of the tests do notrequire a ‘ ‘cooperative’ ‘ infant. Tone,primitive reflexes. and deep tendonreflexes are the mainstay of theexamination.

TONE CHANGES

An infant who has CP may presentwith either low tone or increasedtone of the trunk and/or appendicular

muscles. The assessment of tonelacks precise parameters and often isbased on clinical judgment. However,

a few guidelines are available, al-though they lack specificity. Follow-ing are a few examples appropriate

for clinical examination.Hvpotonia. The anterior scarf sign

is elicited with the infant in the proneposition. Both shoulders are heldagainst the table, and with the headin the midline, the examiner pullsone arm across the infant’s chest to-ward the opposite ear. Increasedrange of motion ofjoints (hypotonia)is indicated if the elbow can bedrawn past the chin. For the lower

extremities, the abductor sign is elic-ited with the baby supine. The kneesare extended and the hips abducted.Abduction greater than 160#{176}suggestsincreased laxity of the hip joints.

Hvpertonia. Assessment of hyper-tonia is difficult if a baby is crying,which is a common problem duringroutine examinations. However, thisdoes not necessarily preclude a

meaningful evaluation. To appreciate

the value of this type of examination.it is helpful to know that when a

newborn is held prone, a tonic laby-rinth reflex results in increased flexor

posturing of trunk and extremities.Placing the newborn baby supine re-suits in a slight decrease in this

flexor posturing toward more exten-sion. As the newborn matures, theflexor posturing in the prone positiondiminishes and extensor tone tends toincrease. The finding of prematuredevelopment of extensor tone, or atthe other extreme, a marked loss offlexor tone in the prone positionshould arouse suspicion of a motorproblem.

If the newborn baby is held inventral suspension, the elbows, knees,

and hips should be flexed and theneck slightly flexed. At about 6 weeksof age, this flexor posturing decreases

but still is present; now the head isusually in line with the trunk. If thehead is hyperextended when the in-

fant is held in ventral suspension atthis early age, this is considered to be

an abnormality in extensor tone andmay reflect an underlying motor dis-turbance. If the same baby is placedon the table prone and the buttocks

are still riding high-that is, abovethe trunk-this would be due to in-creased flexion at the hips. whichshould have lessened by 6 weeks to3 months of age. This is also an ab-normal manifestation of tone.

When the baby is picked up from

the supine position. the head shouldcome up with the trunk at around3 months of age. A persistent headlag can be due to increased extensortone. In fact, if a baby seems to have

good head control at 6 weeks of age,as indicated by the head being held

above the trunk in ventral suspension,one can prove, by picking the babyup from the supine position. that thisis not due to good voluntary controlbut is only a manifestation of in-

creased reflexive extensor tone. If thebaby has good voluntary head con-trol, he or she should be able to bringthe head up in line with the trunk.The head lagging behind is proof thatthe finding of good head control inventral suspension was deceptive.

After ventral suspension is ob-served, the baby should be placed invertical suspension. An infant who

‘ ‘scissors’ ‘ (Fig. I ) after the age of 2months is considered to have in-creased hip adductor tone, which is

an early indicator that the infanteventually may develop more classicsigns of CP.

PRIMITIVE REFLEXES

There is value in testing specificprimitive reflexes during a routine

physical examination. The asymmet-ric tonic neck reflex never should be

obligatory. If the head is turned inone direction and the extremitiesmove into the fencing position with

FIGURE 1. Artist’s rendering of leg

.sei.v.soring tIl(lt i!ldi(’ate.S’ incr(’ase(/ hip

addu tar tone.

FIGURE 2. Asvnzi,u’tric tommie imeek reflex.

4/4 1’(’(Ii(ltil(S in Reviess Vol. /6 No. / / November /995

NEUROLOGYcerebral Palsy

extension on the chin side. the cx-tremities should not appear fixed in

this position for more than 30 sec-

onds while the head is maintained in

a lateral position (Fig. 2). If this oc-

curs, especially if the baby cries at

the same time. the infant has an‘ ‘obligatory’ ‘ asymmetric tonic neckreflex. Its presence. either bilaterallyor unilaterally, often is an early man-

ifestation of CP. A nonobligatory

asymmetric tonic neck reflex present

after 6 months of age also is highlysuspicious.

The crossed extensor reflex testhas lesser value but should be per-formed by applying a noxious stimu-lus to the sole of the foot with theknee extended. The initial reaction is

flexor withdrawal of the contralateralextremity, followed by extension ofthis extremity and adduction. Thisreflex usually is evident up to 4months of age. Its persistence afterthat age suggests a potential motordefect. The is also true for the posi-tive supporting reaction. This reaction

is seen in newborn babies in whom,if the soles of the feet touch a hardsurface, there is an immediate reflex

consisting of plantar flexion of theankle and extension of the knee andhips, seemingly to support his or her

weight. This reflex usually disappears

at about 4 months of age.

DEEP TENDON REFLEXES

To elicit the status of the deep ten-

don reflexes accurately. it is helpfulto have the baby relaxed in the secu-rity of the mother’s lap. The primaryarea of concern is the presence ofhyperreflexia, which indicates an up-per motor neuron lesion. If the hyper-reflexia is truly pathologic, there fre-

quently is an increased sensory inputzone for obtaining a primary motor

response. For instance, if the exam-iner initially percusses over the del-toid and obtains a reflex contraction

of the biceps, this would be consid-ered a 4+ bicep jerk. Additionally.percussion over the shins or anyplace below the patellar tendon thatresults in knee extension is patho-logic. Ankle clonus is not uncommon

among normal infants up to a fewmonths of age, but sustained anklecionus is cause for concern.

The presence of decreased-to-absent deep tendon reflexes usuallyindicates a lower motor neurondisease.

Clinical Presentations of CP

SPASTIC HEMIPARESIS

A baby who eventually develops aspastic hemiparesis rarely shows any

asymmetry of movement in the first

few months of life. In fact, a Mororeflex will not be characterized by

asymmetry of one upper extremity

over the other. If the Moro responseis characterized by this asymmetry,

the examiner should look for a lower

motor neuron lesion on the side ofthe extremity that responded poorly.

It is usually at about 4 months of

age that a mother notices her infanttending to maintain a fisted hand po-

sition on one side compared with the

contralateral extremity. It may be

difficultto discern an asymmetry of

tone or reflexes in the upper extremi-ties in the clinic. Tone and reflex

changes rarely are evident in young

infants and, even if present. having

the baby relaxed enough for an accu-rate measurement frequently is im-

possible. Therefore, if the formal

neurologic examination does not re-sult in confirmatory “hard” signs of

CP, the examiner should not rule out

this possibility, especially if the his-tory indicates early development of“handedness.” It is usually at ap-proximately 6 months of age that

tone and reflex asymmetry in the up-

per extremity evolves. The same

baby may crawl late and, if so, will

use a nonalternating pattern that in-volves pushing off with the arm and

leg on the normal side and draggingthe contralateral extremities. Even at10 months of age. asymmetry in re-

Preterm infants are susceptible to developing a spastic

diplegia, the most common type of disability in CP.

Pediatrics in Review Vol. /6 No. / / November /995 415

NEUROLOGYCerebral Palsy

flex and tone may not be evident inthe lower extremities. However, thesefindings will become more apparentat approximately 12 to 15 monthsof age.

The first sign of spasticity in theupper extremities is tightness of the

elbow flexors and wrist pronators. Bycomparing differences in the ease ofsupination and pronation at the wrist,one may be able to judge any in-

equality in resistance to passivemovement. Spasticity of the upper

extremity features resistance whenattempting supination. In the lowerextremities, the first muscle that de-velops spasticity is usually the gas-

trocnemius. The examiner will noticethat it is more difficult to dorsiflexthe ankle of the involved extremitycompared with the normal one.

Another method for comparingtone is to hold the arms in a position

so that the hands can be “flapped”up and down rapidly. One occasion-ally may be able to make a judgmentof asymmetry in terms of the ease ofIllovement. Flapping of the ankles

can be assessed similarly.

The final extent of the spasticity andthe motor disability may not becomeapparent until 2 to 3 years of age.

ATHETOID CP

Newborns who develop bilirubin en-cephalopathy will show signs of ker-nicterus at about 3 to 5 days of age.The infant will develop a high-pitched cry. have increased extensor

tone manifested as opisthotonos. andhave increased deep tendon reflexes.If the baby survives, the increasedextensor tone will decrease gradually

at about 2 weeks of age, and by 6weeks of age, the tone may be vari-able or possibly normal. Even if theinfant has normal tone, crying willresult in an abnormal exaggeration ofextensor tone. As the infant reaches3 months of age, tone will have de-creased further to the point where thebaby appears “floppy.” Deep tendonreflexes most likely will be within

normal limits at this stage. The pri-mary neurologic finding beyond thedecreased tone is an obligatory asym-

metric tonic neck reflex.This infant will be delayed in

achieving motor milestones, although

the motor delay will not be on thebackground of reflex changes or in-

voluntary movements. For example,

at 10 months of age, the infant will

use a raking movement when reach-ing out for a pellet instead of the cx-pected pincer grasp. This immature

raking motion will be done withoutany involuntary movements. It is notuntil about I 2 to 18 months of age

that the infant will show athetoid-dystonic posturing on voluntarymovement. It is around this period

that the hypotonia gradually changesto increased tone of the rigid or cog-wheel type. During these sequentialchanges, the deep tendon reflexeswill continue to be normal. However,the asymmetric tonic neck reflex willpersist. The hypertonus and the invol-untary movements may increase inseverity gradually over the next year.

These dramatic changes on thebackground of a static encephalopa-thy may cause the pediatrician to sus-pect a progressive central nervoussystem lesion. However, knowingabout the presence of neonatal hyper-bilirubinemia and the natural course

of bilirubin encephalopathy will givethe progressive changes in signs andsymptoms a reasonable explanation.

SPASTIC DIPLEGIA

Many preterm infants who have CP

will develop spastic diplegia. It usu-

ally is manifested initially by delayed

sitting, especially if the trunk is in-volved. Crawling, standing, and am-bulation also will be delayed. Ininfancy, low tone of the lower ex-

tremities may be present. It is notuntil after 1 year of age that hyperto-nia (spasticity) will be evident. How-ever, there are clues to indicate thatthe initial low tone does not suggesta lower motor neuron lesion, but re-flects an upper motor neuron lesion.Increased deep tendon reflexes andoccasionally unsustained bilateralclonus will be present. Also, one maybe able to elicit abnormal posturalreactions. For example, when the

baby is picked up quickly and placedin the vertical position, he or she

may exhibit a scissoring of the legsdue to spasticity of the hip adductors.Also, when the infant is held verti-

cally and the soles touch a hard sur-face, he or she will exhibit a positivesupporting reaction with plantar flex-ion at the ankles and extensions atthe knees and the hips. A positive

supporting reaction usually disap-pears at about 4 to 6 months of age.

Babies who have a spastic diplegiafrequently will not use an alternatingpattern with their lower extremitieswhen crawling. but will exhibit an

‘ ‘army’ ‘ crawl using their upper

extremities.

ATAXIC CP

Babies who have ataxic CP presentwith low tone of trunk and extremi-ties. usually with normal deep tendonreflexes. As they mature, they tend tosupport their weight with their kneesextended so as to lock them in posi-tion, and they use a very wide base

for support. It is rare to see any overtsigns of ataxia, such as an intentiontremor or head titubation in infancy.A complicating factor may be a spas-tic component to the condition. Insuch cases, the infant usually will behypotonic and not spastic. but hyper-

reflexia will indicate the presence ofpyramidal tract involvement.

SPASTIC QUADRIPARESIS

Infants who have this type of CP also

pass through a stage of hypotoniaprior to the appearance of spasticityand increased muscle tone. Earlymanifestations of spasticity are simi-lar to those described in other spasticclinical types and affect both lower

and upper extremities.

Management

Informing the family about a sus-pected or established diagnosis of CPshould be compassionate and factual,but should acknowledge the limita-

tions of early prognostication. Enroll-ment in an early intervention pro-

gram will provide family support forcoping. parental education for han-dling a child at home, and treatment

When assessing a child who has a motor delay, it is

necessary to determine where the pathology exists

anatomically -.. If the brain is the site of the pathology,

the child is considered to have CP.

4/6 Pediatrics in Review Vol. /6 No. / / November /99S

NEUROLOGYCerebral Palsy

to promote motor and other develop-mental skills of the child. PL99-457is a federal law that mandates such

programs in all states.The long-range management of

children who have CP addresses bothmotor dysfunction and associatednonmotor deficits. Equally important

are measures to assist adjustment ofthe family because the home milieuwill affect the child’s emotional andpersonality development.

MOTOR DYSFUNCTION

In general terms, the aim of treatingthe physical disability is to improvefunction and to prevent secondarycomplications of the musculoskeletalsystem. The pediatrician must estab-lish realistic expectations for thechild’s motor function and ensurethat progressive contractures anddeformities do not interfere withoptimal outcome.

Physical therapy is a treatment

used frequently to promote gross mo-tor skills. Methods proposed for CPare numerous, and new OflC5 continue

to emerge. Most techniques focus onspecific aspects of abnormal move-

ment control as a key to successfulremediation. Studies on the efficacyor comparative effectiveness of dif-

ferent therapeutic methods are scarce

or nonexistent.Occupational therapy concentrates

on eye-hand coordination and upperextremity motor control to attain the

highest level of independence in self-care and other activities of daily lifethat involve hand function. Pseudo-bulbar palsy in bilateral impairmentof the motor system leads to oral mo-tor dysfunction manifested as earlysucking, swallowing, and chewingdifficulties. In the hands of trainedoccupational or speech therapists,

proper positioning and feeding meth-ods help to alleviate these problems.Parental involvement and training inspecial feeding techniques should be

emphasized. Early feeding difficultiesoften precede impaired speech

production.

Assistive devices and adaptedfunctional techniques offer compensa-tory means for independence in many

gross and fine motor activities thatotherwise are not feasible to achieve.

Ambulation with crutches or wheel-chair and use of adapted feedingutensils or writing implements are

only some examples. A properly con-structed wheelchair insert can modifyabnormal tone and posture, improvesitting balance, and thereby allowbetter arm use. Rehabilitation engi-neering revolutionized the application

of electronic and computer technol-ogy for disabled persons. Motorizedwheelchairs, nonverbal communica-

tion, and environmental control de-vices have opened up new possibili-

ties for children who have severephysical handicaps but adequate cog-nitive function.

Biofeedback with electromyogra-

phy and auditory signal monitoringhas been used to modify the activity

of selected muscle groups. Improved

gait has been reported in childrenwho have hemiparesis, but long-termfollow-up indicates that the initial

good response was lost by 6 to I 2

months after discontinuation of treat-ment. Biofeedback training of the

orbicularis oris also has been recom-mended to decrease drooling. Experi-

ence with long-range effectiveness islimited.

Bracing usually is prescribed to

correct abnormal posture of the ankleand foot, such as toe walking, in am-bulatory children. Braces extendingabove the knee or hip largely havebeen abandoned as a walking aid forchildren who have CP. An inhibitorywalking cast that maintains the footin good anatomic alignment stretches

a tight heel cord and may decreasethe tendency to toe walk, at leasttemporarily. Positioning braces and

applying splints at rest can help toprevent or delay contractures of theAchilles tendon, hamstring, or hipadductors.

Antispasticity medications affect

muscle tone through different mecha-nisms of action. Diazepam is a cen-

trally acting muscle relaxant withsedative side effects that limit its useas an antispasticity agent. Dantrolene

sodium reduces spastic hypertonicityby decreasing the contractile proper-ties of skeletal muscle fibers. Liverfunction needs to be monitored. al-though hepatotoxicity has not been

reported in children. Baclofen is agamma-aminobutyric acid derivativethat is thought to inhibit neurotrans-

mission. This drug is more effectiveh)r spasticity of spinal origin, but itmay be used for adjunctive treatment

in CP that is accompanied by severespasticity.

Topical injection of phenol. alco-

hol solution, or botulism toxin into

the motor points or motor nerves of aspastic muscle creates a temporary

neurolysis and consequent tone re-duction lasting 4 to 6 months. Theprocedure usually is a temporizingmeasure and most often is applied toalleviate spasticity of the ankle plan-tar flexors and hip adductors.

Surgical therapy-orthopedic sur-gery-often is recommended to im-prove both function and appearanceand to prevent or correct deformities.For example, lengthening of a tightor contracted heel cord corrects toewalking and enhances the efficiencyof gait. Other frequently performedsoft-tissue procedures i nclude releaseof spastic hip and knee flexors andtenotomy of the hip adductors. Inseverely affected children, the pri-

mary reason for surgery is to preventprogressive skeletal deformities thatinevitably follow spastic muscle im-balance. Soft-tissue procedures aloneare not successful when an underly-ing bone deformity already is present.Osteotomy or other bone proceduresneed to be considered in such cases.Acquired hip dislocation resultingfrom spasticity of the hip adductors

and flexors is a serious complicationin bilateral lower extremity involve-

ment that is especially frequent in thenonambulatory group of patients. Inspastic quadriparesis. scoliosis candevelop in the presence or absence ofhip dislocation. After postoperative

immobilization, intensive physicaltherapy is required to regain strengthand function. Long-range mainte-nance of surgical correction is diffi-cult in severely affected childrenwhose active function is limited.

Selective posterior rhizotomy is the

Pediatrics in Review Vol. /6 No. / / November /995 4/7

NEUROLOGYCerebral Palsy

current neurosurgical approach toalleviate spasticity. The procedureconsists of L, to L� laminectomy tolocalize the posterior roots in thecauda equina. Electrical stimulation

applied to the individual rootlets is

monitored by electromyography.Rootlets that produce clonic or sus-

tam stimulus response, especiallywith spread to other muscle groups.are severed because they are thoughtto be responsible for spastic disinhi-bition. The procedure is recom-mended mostly for those childrenwho have spastic diplegia but whocan walk and have adequate strength,

motor control, balance, and reason-able intelligence. Daily physical ther-apy is recommended for 6 to I 2months after surgery . Postoperativecomplications are rare and includetransient paresthesias and loss ofbladder control. Although the proce-dure reduces spastic hypertonicity.whether it significantly influences the

natural course of motor disability

remains a matter of debate.

ASSOCIATED DYSFUNCTIONS

Audiometric testing is part of thediagnostic evaluation. High-frequencyhearing loss is typical of athetoid CP

caused by bilirubin encephalopathyand is present in 70% of cases. Thefrequency of sensori neural hearing

loss is approximately 30% in otherclinical types. Early intervention to

reduce hearing loss is necessary toavoid interference with speech

development.Speech and language development

should be monitored because childrenwho have CP have an increased inci-

dence of dysarthria, verbal dyspraxia,or other central language disorders.Inadequate language development

also may reflect a cognitive deficit.Speech impairment is a sign ofpseudobulbar palsy associated with

bilateral spasticity or athetosis.Speech production defects range froma mild articulation disorder to severedysarthria with complete lack of in-telligible verbal communication.Milder forms of articulation defectscan benefit from speech therapy.Augmentative, nonverbal communica-

tion training for both spoken andwritten language is the method ofchoice when there is a profoundspeech production deficit. Many chil-

dren who have severe motor andspeech disability were thought to beretarded in the past but they provedto have good educational potential byusing this method of communication.

Uncontrolled drooling is anothermanifestation of pseudobulbar palsyand represents a socially embarrass-

ing handicap. Some children improve

spontaneously by 5 to 10 years ofage. For persistent drooling, anticho-linergic drugs, biofeedback, or behav-

ioral intervention may be tried.Transposition of the parotid and/orsubmandibular ducts, extirpation of

the submandibular gland, or resectionof the chorda tympani are surgicalprocedures for redirecting or decreas-ing salivation.

There is no consensus as to theoptimal surgical approach for control-ling drooling. Most surgeons report a60% to 80% success rate with any of

the techniques used. Depending onthe surgical approach, complications

include xerostomia, thick secretionsthat impair the ability to swallow

food, an increase in dental care, andpain and swelling of the parotidgland. Rerouting the parotid duct to

the posterior pharynx may increasethe pulmonary complications of pos-tenor drooling. Treatment should bebased on assessment of each child’sdrooling problem.

Assessment of vision is part ofrouti ne evaluation. Refracti ye errors

and retinopathy of prematurity areassociated visual complications inCP. The incidence of strabismus isapproximately 75%, with the highestfrequency seen in the spastic clinical

types of CP. Timely referral to an

ophthalmologist and early treatmentwill prevent amblyopia.

Approximately 50% of the childrenwho have CP develop some form ofseizure disorder. The highest inci-

dence is in those who have spastichemiparesis and quadriparesis. Atypi-

cal psychomotor seizures may be dif-ficult to recognize. The choice ofanticonvulsant medications dependson the type of seizure disorder. Side

effects on behavior and alertness alsoshould be considered.

Assessment of intelligence in thosewho have CP requires the skills of a

psychologist experienced with physi-cal disabilities. Mental retardationoccurs in about 50% of those af-fected. and children of normal intelli-

gence may have a learning disability.Planning for appropriate educationalplacement should start before the

child reaches school age. Intellectualand learning abilities are the deciding

factors for selecting the most suitableschool. Environmental adaptationscan accommodate physical disability

and are mandated in the United

States by PL94-142, the Education ofAll Handicapped Children Act. Chil-dren who require special educationshould be mainstreamed for selected

activities.

The energy expenditure for walk-ing and other physical activities isseveral times above that of normal in

motor disabilities. This should be

considered in dietary guidance ofactive children who have CP. On theother hand. a low level of physicalactivity in severely handicapped chil-dren may lead to obesity. The in-creased weight may increase the en-ergy expenditure of a limited

ambulator to such a degree that awheelchair existence becomes neces-

sary. This is not an unusual scenarioamong adolescents.

Participation in “adaptive” sports

should be encouraged. Swimmingand horseback riding seem to be themost popular for children who have

CP, but virtually all sports can beadapted to a motor disability. espe-cially with wheelchair use.

Psychosocial Guidance

Anticipatory guidance of the familyand, at the appropriate age, of thechild is perhaps the most complicatedaspect of management. Preoccupationwith treatment of the motor disability

should not distract attention from theneed to foster an independent, resil-ient personality, with determinationand drive to succeed. Children whohave CP should have a variety ofsocial and recreational opportunities

similar to those of nondisabledyoungsters. Acquisition of good so-

cial skills during childhood is essen-tial for attaining maximal functionaland vocational potential in adult life.

Outcome

In predicting long-range outcome,

one must consider multiple variables.Physical and intellectual abilities arethe primary determinants of func-

PIR QUIZ7. You have been asked to see a pre-

term newborn in the nursery. The

mother had a difficult delivery 6

weeks before her expected date of

delivery and is very concerned

about her baby. History states the

baby had a I -minute Apgar score

of 3. Your findings indicate that the

baby is hypotonic, as demonstrated

by an anterior scarf sign, and has

normal deep tendon reflexes. You

can tell the mother that:

A. Diagnosis of cerebral palsy is

difficult before 6 months of age.

B. Most infants who develop cere-

bral palsy are born prematurely.

C. Once cerebral palsy develops, it

will be progressive.

D. There is a 50-50 chance that

her baby will develop cerebral

9. Whitney is a 15-month-old female

infant who has been slow in sitting,

crawling. and standing amid has de-

veloped sonic spasticity of her legs.

She was delivered prematurely but.

despite some jaundice. seemed to

progress well as a newborn. Her

mother has been told that Whitney

has spastic diplcgia and wants to

know how this could have hap-

pened. In counseling her, you can

explain that the most common

cause of spastic diplegia is:

A. Adverse prenatal problems.

B. Birth trauma.

C. Blood incompatibility.

D. Obstetric complications.

E. Prematurity.

palsy.

E. The low Apgar score indicates a

high risk of cerebral palsy.

8. Roy is a I 2-month-old male infant

you have been following since his

birth. He developed severe hyper-

bilirubinemia at 3 days of age and

received one exchange transfusion

to lower his bilirubin level. You

are concerned that he may be de-veloping athetoid cerebral palsy.

Which one of the following find-

ings would increase your concern?

A. Increased deep tendon reflexes.

B. Marked hypertonia.

C. Persistent asymmetric neck

10. You should advise Whitney’s

mother that regular evaluation is

essential. Complications are not

infrequent, and visual. hearing. in-

telligence, speech development, and

orthopedic examinations are neces-

sary. She should know that most

complications can be helped if rec-

ognized and treated early. The most

common complication is:

A. Hearing loss.

B. Mental retardation.

C. Orthopedic deformities.

D. Seizure disorder.

E. Strabismus.

reflex.

D. Pincer grasp reaching for

pellets.

E. Sitting with ease.

Peetie,tru’,s’ in Review Vol. /6 No. / / November /995

NEUROLOGYCerebral Palsy

tional potential. hut the achievementof these expectations also depends onpsychosocial adjustnient.

Children who have hemiparesiswalk by I .5 to 3 years of age: 80C/c

to 90C/ of children who have diple-gia. 7O��k of those who have dyskine-51a, and SOCk who have quadriparesisattain sonic mode of ambulation. Inthese clinical types the ability tomaintain independent sitting by I .5 to2 years oilers a good prognosis forconimunity anibulation. Children who

learn to sit between 2 and 4 yearsusually heconie household ambula-

tors, and SOIT1� may walk short dis-

tances outdoors with assistive de-vices. Walking is not expected ofchildren who cannot sit by 4 years of

age. Despite the unilateral hand im-pairnient. hemiparesis does not cx-dude independence in daily activi-

ties. Motor control of the upperextremities is adequate to performactivities of daily living in diplegia

and usually in cases of mild ambula-tory quadriparesis. Sonic childrenwho have quadriparesis and rely on

wheelchair mobility may achieve par-tial independence in self-care. About25% of this group requires help for

all activities. Athetoid and ataxicniovement disorders tend to compro-

Illise fine hand dexterity to a greater

extent than ambulation. Mental retar-

dation delays hut does not excludewalking if it is permitted by the mo-tor disability. Achievenients in dailyliving skills are consistent with intel-lectual competence. regardless of thedegree of physical disability.

SUGGESTED READINGAndre-Thomas S. (‘hcrni Y . Sai mite-Antic

l)argmrssic� S. �rtic neurological cxanimnatn)n

of the infant. Little (‘1mm/i (7inic in

1)evelopineiit Medi(’iil(’. No I . London.

Emigland: Spastics Society: I 9#{244}()

Niolnar (iF. cd. !‘((li(lti’i(’ Reluibilitation. ed 2.

E3altinnrc. Md: \Villianis and \Vilkins: I 991

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Nelson KB. Ellenhcrg JM. Apgar scores as

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