health supervision for children with achondroplasia

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AMERICAN ACADEMY OF PEDIATRICS

CLINICAL REPORTGuidance for the Clinician in Rendering Pediatric Care

Tracy L. Trotter, MD; Judith G. Hall, OC, MD; and the Committee on Genetics

Health Supervision for Children With Achondroplasia

ABSTRACT. Achondroplasia is the most common con-dition associated with disproportionate short stature.Substantial information is available concerning the nat-ural history and anticipatory health supervision needs inchildren with this dwarfing disorder. Most children withachondroplasia have delayed motor milestones, prob-lems with persistent or recurrent middle-ear dysfunction,and bowing of the lower legs. Less often, infants andchildren may have serious health consequences related tohydrocephalus, craniocervical junction compression, up-per-airway obstruction, or thoracolumbar kyphosis. An-

ticipatory care should be directed at identifying childrenwho are at high risk and intervening to prevent serioussequelae. This report is designed to help the pediatriciancare for children with achondroplasia and their families.Pediatrics 2005;116:771783; achondroplasia, short stat-ure, children, health supervision.

ABBREVIATIONS. OFC, occipital-frontal circumference; CT, com-puted tomography.

INTRODUCTION

T

his clinical report is designed to assist the pe-diatrician in caring for children with achondro-plasia confirmed by radiographs and physical

features. Although pediatricians usually first seechildren with achondroplasia during infancy, occa-sionally they are called on to advise a pregnantwoman who has been informed of the prenatal di-agnosis of achondroplasia or asked to examine anewborn to help establish the diagnosis. Therefore,this report offers advice for these situations as well.

Substantial new information has appeared sincepublication of the first policy statement on healthsupervision of children with achondroplasia.1 In par-ticular, a great deal has been learned about the mo-lecular genetics of the disorder.2 In addition, a morecomplete understanding of how certain serious com-

plications can be minimized or avoided has accrued.3The new information is incorporated into this report,which is a revision of the original policy statement.

Achondroplasia is the most common condition as-sociated with severe disproportionate short stature.4

The diagnosis can usually be made on the basis ofclinical characteristics and very specific features on

radiographs, which include contracted base of theskull, square shape of the pelvis with a small sacro-sciatic notch, short pedicles of the vertebrae, rhi-zomelic (proximal) shortening of the long bones, tri-dent hands, a normal-length trunk, proximal femoralradiolucency, and (by midchildhood) a characteristicchevron shape of the distal femoral epiphysis. Otherrhizomelic dwarfing disorders such as hypochondro-plasia and thanatophoric dysplasia are part of thedifferential diagnosis, but achondroplasia usually

can be distinguished from them because the changesin hypochondroplasia are milder and the changes inthanatophoric dysplasia are much more severe andinvariably lethal. Achondroplasia is an autosomaldominant disorder, but approximately 75% of casesrepresent new dominant mutations. Achondroplasiais caused by mutation in the gene that codes for thefibroblast growth factor receptor type 3 (FGFR3).57

Because virtually all of the causal mutations occur atexactly the same place within the gene,7 moleculartesting is straightforward. It is not necessary to per-form molecular testing in every child with a clinicaldiagnosis of achondroplasia. However, FGFR3 test-

ing should be performed in children who are in anyway atypical or in circumstances in which differen-tiation from similar disorders, such as hypochondro-plasia, is not certain. Such children also should bereferred for clinical genetic evaluation.

A great deal is known about the natural history ofachondroplasia that can be shared with the family.3,8

The average adult height in achondroplasia is ap-proximately 4 ft for men and women (Figs 1 and 2).9

The most common complication, occurring in adult-hood, is related to lumbosacral spinal stenosis withcompression of the spinal cord or nerve roots.10,11

This complication is usually treatable by surgicaldecompression if it is diagnosed at an early stage.

Most children with achondroplasia do well. How-ever, children affected with achondroplasia com-monly have delayed motor milestones (Fig 3),12,13

otitis media, and bowing of the lower legs.14 Lesscommonly, infants and children may have serioushealth consequences related to hydrocephalus,craniocervical junction compression, upper-airwayobstruction, or thoracolumbar kyphosis. Althoughthey are less common, anticipatory care should bedirected at identifying children who are at high riskand intervening to prevent serious sequelae. Mostindividuals with achondroplasia are of normal intel-ligence and are able to lead independent and pro-

The guidance in this report does not indicate an exclusive course of treat-

ment or serve as a standard of medical care. Variations, taking into account

individual circumstances, may be appropriate.

doi:10.1542/peds.2005-1440

PEDIATRICS (ISSN 0031 4005). Copyright 2005 by the American Acad-

emy of Pediatrics.

PEDIATRICS Vol. 116 No. 3 September 2005 771


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ductive lives.15 Because of their disproportionateshort stature, however, a number of psychosocialproblems can arise. Families can benefit from antic-ipatory guidance and the opportunity to learn fromother families with children of disproportionateshort stature.

The consensus-based guidance in this report isdesigned to help the pediatrician care for childrenwith achondroplasia and their families. Issues thatneed to be addressed at various ages are discussed(Table 1). These suggestions are not appropriate forother chondrodysplasias, because each type has itsown natural history, complications, and specificguidelines. Irrespective of the availability of theguidance in this report, it is important that pediatri-cians and parents also consult a physician with spe-cial experience and expertise concerning achondro-plasia early in the childs life, because this reportonly provides generally applicable suggestions that

must be tailored to a particular childs condition andneeds.

THE PRENATAL VISIT

Pediatricians may be called on to counsel expect-

ant parents whose fetus has achondroplasia or issuspected to have achondroplasia because of recog-nition on ultrasonography of disproportionate smallstature. In some settings, the pediatrician will be theprimary resource for counseling a family. At othertimes, counseling may already have been providedto the family by a clinical geneticist and/or the ob-stetrician. Because of a previous relationship with thefamily, however, the pediatrician may be called on toreview this information and assist the family in thedecision-making process.

The diagnosis of achondroplasia in the fetus ismade most often with certainty when 1 or both par-ents have this condition. In this circumstance, the

Fig 1. Height for males with achondroplasia(mean 2.8 standard deviation) comparedwith normal standard curves. The graph wasderived from 189 males. (Reproduced withpermission from J Pediatr. 1978;93:435-438.)

772 HEALTH SUPERVISION FOR CHILDREN WITH ACHONDROPLASIA


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parents are usually knowledgeable about the disor-der, the inheritance, and the prognosis for the off-spring. More often, diagnosis of achondroplasia isfirst suspected late in gestation on the basis of long-

bone foreshortening incidentally discovered by ul-trasonography. With the frequent use of ultrasonog-

raphy, many cases of achondroplasia are firstidentified prenatally (after 26 weeks of gestationalage). However, disproportionately short limbs areobserved in a heterogeneous group of conditions.Misdiagnosis and inaccurate prenatal counseling offamilies is common.16 Confirmation of diagnosis

based on ultrasonographic features characteristic ofachondroplasia can be provided by molecular testing(FGFR3 mutational testing) of prenatal specimens. Ifno such confirmation has yet been completed, cau-tion should be exercised when counseling the family.In this circumstance, the pediatrician should discussthe tentative nature of the diagnosis and alternativesthat may explain the identified features. The pedia-

trician should also discuss the natural history ofachondroplasia, because it is the most likely expla-nation for the findings. In cases in which the diag-nosis is unequivocally established either because ofthe familial nature of the disorder or by prenatalmolecular diagnosis (chorionic villus sampling at

1113 weeks gestation or amniocentesis after 15weeks gestation), the pediatrician may consider thefollowing steps as appropriate.

1. Review, confirm, and demonstrate laboratory orimaging studies leading to the diagnosis.

2. Explain the mechanisms for occurrence of achon-droplasia in the fetus and the recurrence risk forthe family.

3. Remember that at least 75% of cases of achondro-plasia occur in families in which both parentshave average stature. In those cases, achondropla-sia in the offspring occurs because of a mutationin the gene.

Fig 2. Height for females with achondroplasia(mean 2.8 standard deviation) comparedwith normal standard curves. The graph wasderived from 214 females. (Reproduced withpermission from J Pediatr. 1978;93:435-438.)

AMERICAN ACADEMY OF PEDIATRICS 773


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4. Review the natural history and manifestations ofachondroplasia, including variability.3

5. Discuss additional studies that should be per-formed, particularly those to confirm the diagno-sis in the newborn period. If miscarriage, still-

birth, or termination occurs, confirmation of

diagnosis is important for counseling familymembers about recurrence.6. Review currently available treatments and inter-

ventions. This discussion needs to include the ef-ficacy, complications, adverse effects, costs, andother burdens of these treatments. Discuss possi-

ble future treatments and interventions.7. Explore the options available to the family for the

management and rearing of the child using a non-directive approach. In cases of early prenatal di-agnosis, these options may include discussion ofpregnancy termination, continuation of preg-nancy and rearing of the child at home, foster care,

or adoption. If adoption is planned to anotherfamily, contact may be made with the Little Peo-ple of America adoption service.17

8. If the mother is affected with achondroplasia, in-form her that a cesarean delivery must be per-formed because of the characteristic small pel-vis.18 A mother affected with achondroplasia maydevelop respiratory compromise during the thirdtrimester of pregnancy, so baseline pulmonaryfunction studies should be performed. Homozy-gous achondroplasia can be diagnosed prenatallywith molecular testing of the fetus, by either cho-rionic villus sampling or amniocentesis. A preg-nancy at risk of homozygosity should be followed

with ultrasonographic measurements at 14, 16, 18,22, and 32 weeks of gestation to distinguish ho-mozygosity or heterozygosity from normal growthpatterns in the fetus.

9. When both parents are of disproportionate shortstature, assess the possibility of double het-

erozygosity19 or homozygosity for achondropla-sia. Some forms of double heterozygosity lead tolife-threatening problems19; infants with homozy-gous achondroplasia usually are stillborn or dieshortly after birth.20

HEALTH SUPERVISION FROM BIRTH TO

1 MONTH OF AGE: NEWBORNS

Examination

1. Confirm the diagnosis by radiographic studies(the diagnosis of approximately 20% of patients

with achondroplasia has been delayed in the pastbecause it was not suspected on physical exami-nation in the newborn period, and consequently,no radiographs were obtained).

2. Document measurements, including occipital-frontal circumference (OFC), body length, and

body weight; plot these measurements on achon-droplasia-specific growth charts (Figs 1, 2, and47). Review the phenotype with the parents anddiscuss the specific findings with both parentswhenever possible.

3. The OFC should be measured at every pediatriccontact during the first year (Figs 4 and 5).

Fig 3. Developmental screening tests in achondroplasia. The bar scale shows the percentage of achondroplastic children passing the item;the black triangle on top of the bar shows the age at which 90% of normal children pass the same item. The graphs were derived from197 affected individuals, obtained by questionnaire. (Reproduced with permission from Am J Med Genet. 1981;9:19-23.)



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TABLE

1.

AchondroplasiaGuidelin

esforHealthSupervision

Prenatal

Infancy,1moto1y

ofAge

EarlyChildhood,1to5yofAge

LateChi

ldhood

Adolescence

Neonatal

2mo

4

m

o

6mo

9mo

12mo

15mo

18mo

24mo

3 y

4y

5to13y,

Annual

13to21y,Annual

Diagnosis

Radiography

Wheneverthediagnosisissuspected

Reviewphenotype


Reviewproportions


MoleculartestingFGFR3

See

text

Whendiagnosisisno

tcertain

Geneticcounseling

Earlyintervention

X

Recurrencerisks

X

X

X

Reproductiveoptions

X

X

X

Familysupport

X

X

X

X

X

Supportgroups

X

X

X

X

X

Long-termplanning

X

X

X

X

Medicalevaluation

Growth/weight/OFC

X

X

X

X

X

X

X

X

X

X

X

Orthopedicconsult

Neurologyconsult

Hearing

XR

XR

XR

XR

Socialreadiness

S

S

S

S

Orthodontics

R

R

R

Speech

S/O

S

/O

S/O

S/O

O

O

Medicalevaluation

Radiography,onlytomake

diagnosisorif

complication

CT/MRIbrain/cervical

spine

X

Polysomnography

X

Asindicated

3

3

3

3

3

3

3

3

3

3

3

Socialadjustment

Psychosocial

S

S

S

S

S

Behavioranddevelopment

S/O

S/O

S/O

S/O

S/O

S/O

S

/O

S/O

S/O

S/O

School

O

O

O

Sexuality

X

Theseguidelinesensurecompliancewit

hAAPrecommendationsforpreventivepediatrichealthcare.

FGFR3indicatesfib

roblastgrowthfactorreceptortype3;X,

tobeperformed;S,subjective,by

history;O,objective,byastandardtestingmethod;R,discussreferraltoaspecialist;3,continuetomonitor.



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Anticipatory Guidance

1. Discuss the specific findings of achondroplasiawith the parents, including the following:

Autosomal dominant inheritance: approxi-mately 75% of cases are new mutations. Germ-line mosaicism (in which some germ cells arederived from a normal cell line and some arefrom a cell line with a mutation) has been re-ported, but the risk of recurrence in sporadiccases is less than 1%.2123

Most individuals with achondroplasia have nor-mal intelligence and normal life expectancy.

Although serious problems may arise duringinfancy, such problems affect only 5% to 10% ofinfants with achondroplasia.

Growth hormones, other drug therapies, andfood or vitamin supplements are not effective in

significantly increasing stature. Growth-hor-mone therapy may result in a transient increasein growth rate. However, the salutary effectsdiminish with continued treatment. No study

has clearly demonstrated a significant benefitwith respect to ultimate adult stature.24,25 Ifelected, such treatment should be consideredonly within a research setting. Extended limblengthening using a variety of techniques has

been used far more elsewhere than in NorthAmerica. It can result in substantial increases inultimate height.26,27 However, it is arduous, notwithout risk, and costly. Most families alterna-tively choose to modify the environment to ac-commodate the child rather than the converse.

Special achondroplasia growth curves and in-fant development charts have been developed(Figs 17); the final expected adult height for

Fig 4. Head circumference for males with achondro-plasia compared with normal curves (dashed lines).The graph was derived from 189 males. (Reproducedwith permission from J Pediatr. 1978;93:435-438.)



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persons with achondroplasia is approximately 4ft.9

2. Discuss the following possible severe medicalcomplications and methods of prevention:

Unexpected infant death occurs, in the absence

of aggressive evaluation, in approximately 2% to5% of all infants with achondroplasia.28,29 Thisseems to result from central apnea arising sec-ondary to compression of arteries at the level ofthe foramen magnum.28 In addition, the univer-sally small foramen magnum may result in ahigh cervical myelopathy.30,31 However, withappropriate assessment and intervention, bothrisks can be minimized.31 Parents should be ad-vised to use an infant seat or infant carrier thathas a firm back that supports the neck and to usea rear-facing car safety seat for as long as possi-

ble. They should be counseled to avoid use ofproducts like mechanical swings and carrying

slings to limit uncontrolled head movementaround the small foramen magnum. There areinstances in which infants with achondroplasiawho showed no clinical abnormality by exami-nation and who were asymptomatic have died

from this complication. Given this, and becauseit can be life saving, care of every infant withachondroplasia should include assessment forcraniocervical junction risks, which includescareful neurologic history and examination,neuroimaging, and polysomnography.31 Neuro-imaging can be by computed tomography (CT)with thin cuts and bone windows31 or magneticresonance imaging (MRI),32,33 each of which has

benefits and disadvantages: CT allows directcomparison of foramen magnum size with pub-lished achondroplasia standards and often can

be accomplished without sedation or anesthesia but does not allow direct visualization of the

Fig 5. Head circumference for females with achondro-plasia compared with normal curves (dashed lines).Data were derived from 145 females. (Reproduced withpermission from J Pediatr. 1978;93:435-438.)



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neural elements of interest; MRI provides such adirect assessment of the brainstem and uppercervical spinal cord, but no standards for esti-mation of foraminal size by MRI are available,and currently it cannot be performed routinelywithout sedation. Rapid development of imag-ing technology suggests that alternative meth-ods may become appropriate in the future.

If severe problems are found (eg, marked abnor-mality by neurologic examination, such as pro-found hypotonia or sustained ankle clonus;markedly diminished foramen magnum sizecompared with achondroplasia standard; sub-stantial deformation of the upper cervical spinalcord; hypoxemic episodes with minimal oxygensaturations below 85%31), referral to a neurosur-

Fig 6. Height-by-weight standards in achondroplasia: males. (Reproduced with permission from Am J Med Genet. 1996;62:255-261.)

Fig 7. Height-by-weight standards in achondroplasia: females. (Reproduced with permission from Am J Med Genet. 1996;62:255-261.)



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geon or other physician skilled and experiencedin the care and treatment of neurologic prob-lems in children with achondroplasia should beinitiated.34

Hydrocephalus is a lifelong risk but is mostlikely to develop during the first 2 years.35 OFCshould be monitored carefully during this time.If the OFC is large or crosses percentiles on theachondroplasia-specific head-circumference chart,it is appropriate to refer the infant to a pediatricneurologist or pediatric neurosurgeon. BaselineCT or MRI (performed in conjunction with im-aging of the craniocervical junction) is valuableif there is concern about possible hydrocepha-lus. Repeating neuroimaging to assess change inventricular size should be considered if there isacceleration of head growth compared withachondroplasia standards or if other signs like

bulging, hard fontanelle, or symptoms of un-usual lethargy or intractable irritability develop.Both ventriculomegaly and excessive extra-axialfluid are common benign accompaniments ofachondroplasia35 and should not be misinter-preted as indicative of need for shunt place-

ment. Neural ultrasonography may be used tofollow these clinical findings.

Restrictive pulmonary disease occurs in lessthan 5% of children with achondroplasia whoare younger than 3 years.36 Living at high ele-vation markedly increases the risk that restric-tive problems will develop. If there are signs ofrespiratory distress or evidence of poor weightgain despite adequate caloric intake, pulseoximetry (during feeding, when crying, and atrest) should be considered to monitor oxygen-ation.

Most infants with achondroplasia develop a tho-

racolumbar kyphosis. More severe kyphosis isassociated with unsupported sitting before thereis adequate trunk muscle strength.37,38 Parentsshould be counseled to avoid unsupported sit-ting and to avoid devices that cause curved sit-ting or C sitting, such as umbrella-stylestrollers and soft canvas seats during the firstyear of life. Use of feeder seats for upright po-sitioning should be recommended. If severe ky-phosis appears to be developing, consider a pe-diatric orthopedic surgical assessment todetermine if bracing is needed.38

The common complication of spinal stenosis

rarely occurs in childhood but manifests in olderindividuals with numbness, weakness, and al-tered deep tendon reflexes.30 Severe thoraco-lumbar kyphosis is one mechanism that can giverise to spinal stenosis. It is for this reason thatunsupported sitting before there is adequatetrunk muscle strength is discouraged.

Anesthesia risk:39 if an individual with achon-droplasia needs to have anesthesia and surgery,the following should be considered:(a) Care must be taken in manipulation of the

neck, because uncontrolled neck movement(as may occur with intubation) could lead tounintentional spinal cord compression sec-

ondary to constriction of the foramen mag-num.

(b) Care should be taken to ensure that medica-tion dosages are appropriate for size.

(c) Access to veins is sometimes difficult be-cause of lack of full extension at the elbow.

(d) Generally, spinal anesthesia should beavoided, particularly when there is kyphosisor severe lumbar lordosis, because of limitedspace within the spinal canal.

(e) General anesthesia should be strongly con-sidered for cesarean delivery for pregnantwomen with achondroplasia (they will allrequire caesarian delivery because of con-tracted pelves), because use of epidural an-esthesia in these women requires special skilland expertise.40/P

3. Discuss the potential psychosocial implicationsfor both parent and child related to disproportion-ate short stature. Refer the affected individual orthe parent of an affected individual to a supportgroup such as Little People of America (also seeResources for New Parents). If parents do notwish to join a group, they may want to meet with

or talk to other affected individuals or parents.Remind parents that most individuals with achon-droplasia lead productive, independent lives.

4. Discuss with the parents how to tell their familyand friends about their childs growth problem.

5. Supply the parents with educational books andpamphlets (see Resources for New Parents).

6. Discuss the realistic functional problems for af-fected individuals.

7. Discuss individual resources for support, such asfamily, clergy, social workers, psychologists, andfriends.

8. Review the prenatal diagnosis and recurrence

risks for subsequent pregnancies.HEALTH SUPERVISION FROM 1 MONTH TO

1 YEAR OF AGE: INFANCY

Examination1. For infants not diagnosed in the newborn period,

arrange for neuroimaging and polysomnographyat the time of diagnosis.

2. Assess growth and development in comparisononly with children with achondroplasia (Figs 17).

3. Perform physical examination.4. Review head growth on achondroplasia-specific

head-circumference charts.

5. Refer the infant to a pediatric neurologist or pe-diatric neurosurgeon if head size is disproportion-ately large or crosses percentiles, if there are signsor symptoms of hydrocephalus, or if there areindicators of possible craniocervical junction com-pression, including excessively brisk reflexes,asymmetric reflexes, ankle clonus, extreme hypo-tonia, or early hand preference.10,35

6. Consider repeating neuroimaging studies if thereis acceleration of head growth, severe persistinghypotonia, or any signs of craniocervical junctioncompression.3134 Growth of the foramen mag-num may be compared with achondroplasia-spe-cific standards.41



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7. Check motor development and discuss develop-ment; note on the milestone charts for achondro-plasia. Expect motor delay but not social or cog-nitive delay.12,13 Check for serous otitis media.Review risk at 6 to 12 months of age. Formal

behavioral audiometric assessment should becompleted at 9 to 12 months of age. Languagedelay may be present secondary to conductivehearing loss.

8. Continue to monitor for progression of kyphosisat the thoracolumbar junction. It is recommendedthat parents avoid carrying a child with achondro-plasia in curled-up (C-sitting) positions. Certaintypes of child carriers, mechanical swings, jump-ers, and umbrella-style strollers tend to increaserisk for gibbus. Unsupported sitting should beavoided.37,38 Parents and therapists should be in-structed to provide back support during the firstyear of life. If severe kyphosis appears to be de-veloping, consider pediatric orthopedic surgicalassessment to determine if bracing is needed.38

9. Be aware that external rotation of the hips is com-monly present and usually disappears spontane-ously when the child begins to bear weight. This

finding does not require bracing for the infant.


1. Review the personal support available to the fam-ily.

2. Review contact with support groups.3. Observe the emotional status of parents and in-

trafamily relationships.4. Discuss early-intervention services and the impor-

tance of normal socializing experiences with otherchildren.

5. Ask the parents whether they have educated theirfamily members about achondroplasia; discuss

sibling adjustment.6. Review the increased risk of serous otitis media

because of short eustachian tubes. Indicate that anear examination is appropriate with any persistentor severe upper respiratory tract infection or whenparents suspect that ear pain may be present.

7. Advise parents to avoid infant carriers that curlup the infant. This does not apply to car safetyseats, which should always be used during auto-mobile travel. A rear-facing car safety seat should

be used to the highest weight allowed by a con-vertible seat (2530 lb).

8. Discuss filing for Supplemental Security Income

benefits as appropriate.

HEALTH SUPERVISION FROM 1 TO 5 YEARS OFAGE: EARLY CHILDHOOD

Examination

1. Assess the childs growth and development asplotted on the achondroplasia growth charts.

2. Continue to follow rate of head growth on theachondroplasia-specific head-circumference charts.

3. Continue to watch for thoracolumbar gibbus (ky-phosis). Discuss avoiding the use of walkers,

jumpers, or backpack carriers. Any kyphosispresent should disappear as the child begins to

bear weight. Lumbar lordosis usually developsbut rarely requires specific intervention. Weight bearing and walking may occur late; however,they are expected by 2 to 2.5 years of age. Whenweight bearing begins, the external rotation ofthe hips should self-correct to a normal orienta-tion within 6 months.

4. Anticipate some bowing of the legs. Many chil-dren will also have instability of the soft tissuessurrounding the knee and internal tibial torsion.

If positional deformity and instability leads todifficulty walking, a thrust at the knee (uncon-trolled lateral or medial movement with weight

bearing), or chronic pain, consult a pediatric or-thopedist.14

5. Check the childs hips for hip-flexion contrac-tures. Prescribe exercises that may decrease lum-

bar lordosis and hip-flexion contractures if indi-cated. Check the hips for external rotation. Referthe child to a pediatric orthopedist if necessary.

6. Screen hearing each year. If otologic history,hearing screening, or speech development raiseconcerns about hearing, formal audiologic as-

sessment should be obtained.7. Perform speech evaluation at no later than 2years of age. If speech is delayed, conductivehearing loss attributable to chronic serous otitismedia should be excluded.

8. Watch for obstructive sleep apnea secondary tosmaller-than-average airway size plus physio-logic adenoidal hypertrophy.4244 Most childrenwith achondroplasia snore. However, if obstruc-tive apnea or disordered breathing in sleep issuspected (increased retraction, glottal stops,choking, intermittent breathing, apnea, deepcompensatory sighs, secondary enuresis, recur-rent night-time awakening or emesis), then ad-ditional pulmonary evaluation and polysomnog-raphy are indicated.

9. Be aware that gastroesophageal reflux may bemore common in children with achondroplasiaand may be more common in those with neuro-respiratory complications.45 If reflux is severe, inaddition to usual treatments, consider referral toa pediatric specialist with experience in treatinggastroesophageal reflux in infants and children.

10. Do not misinterpret greater-than-average sweat-ing as indicative of serious medical problems; itis normal in children with achondroplasia.

11. In rare instances in which diagnosis of achondro-plasia is delayed beyond 1 year of age, determineif neuroimaging is needed on the basis of clinicalsigns and symptoms.


1. Consider adapting the home so that the child canbecome independent (eg, lower the light switches,use lever door handles and lever sink faucets, makethe toilet accessible, and supply step stools) (seeResources for Parents).

2. Determine if an occupational therapy consulta-tion is needed.



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3. Discuss adapting age-appropriate clothing withsnapless, easy-opening fasteners and tuckableloops.

4. Discuss adaptation of toys, especially tricycles, toaccommodate short limbs.

5. Discuss adaptation of toilets to allow comfort-able, independent use, with an extended wandfor wiping if needed.

6. Discuss the use of a stool during sitting so thatthe childs feet are not hanging. Feet need sup-port while the child is sitting at a desk, in a chair,or on the toilet. A cushion behind the childs backmay be required for good posture and to preventchronic back pain. Counsel parents for optimalprotection to use a convertible rear-facing carsafety seat to the highest weight and height al-lowed by the manufacturer of the seat.46 A rear-facing seat provides the best support protectionand positioning angle for a child with macro-cephaly and skeletal dysplasia. Parents may ben-efit from suggestions for behavioral interventionto promote continuing the rear-facing position aslong as possible.47

7. Review weight control and eating habits to avoid

obesity, which often becomes a problem in mid-to late childhood.48

8. Discuss orthodontic bracing in the future and thepossible need for early orthodontic assessment toconsider palatal expansion.

9. Encourage the family to develop activities inwhich the child can take part; avoid gymnastics,diving, trampolines, and collision sports.

10. Discuss how to talk with the child and friends orfamily members about short stature.

11. Encourage preschool attendance so that the childcan learn to socialize in an age-appropriate way,and work with parents to prepare the teacher

and the other children so that the child is notgiven unnecessary special privileges.12. Discuss toileting at school and special prepara-

tions needed by the school because of the childsshort stature (see Resources for Parents).

HEALTH SUPERVISION FROM 5 TO 13 YEARSOF AGE: LATE CHILDHOOD

Examination

1. Assess and review the childs growth, develop-ment, and social adaptation.

2. Plot measures on achondroplasia weight-by-height grids (Figs 6 and 7).

3. Review weight control.48 The child may need torestrict food intake and eat less than an average-sized child eats.

4. Complete a general and neurologically orientedphysical examination.

5. Check deep tendon reflexes yearly for asymmetryor increased reflexes that suggest spinal stenosis.

6. Continue to assess history for possible obstructivesleep apnea.

7. Test hearing each year.


1. Determine school readiness.

2. Discuss preparation of the school and teacher fora child with short stature (see Resources forParents).

3. Prepare the child for others questions and curi-osity. Be sure the child can explain why he or sheis short and can ask for help in an appropriateway. Children with achondroplasia usually areincluded in the regular education program.

4. Suggest adaptive aids for the school to cope withheavy doors, high doorknobs, reaching for the

blackboard, foot support, and a regular-sizeddesk. Also, be sure that the child can use therestroom independently (see Resources for Par-ents).

5. Counsel parents to use a child safety seat with afull harness to the highest weight allowed by themanufacturer of the seat and then to transition tothe belt-positioning booster seat for optimal seat-

belt positioning.46

6. Review socialization and foster independence.7. Discuss contact with support groups. They are

especially valuable at this age.8. Consider obtaining an orthopedic evaluation

when the child is approximately 5 years of age to

make appropriate treatment plans if necessary.9. Emphasize correct posture and encourage the

child to consciously decrease lumbar lordosis bytucking the buttocks under. If lordosis is se-vere, consider physical therapy referral to teachlower abdominal muscle strengthening and pel-vic rotation.

10. Develop an activity program with acceptable ac-tivities such as swimming and biking. The childshould avoid gymnastics and collision sports be-cause of the potential for neurologic complica-tions secondary to cervical spinal stenosis. If soc-cer is played, heading should be prohibited.

11. Review orthodontic and speech status.

HEALTH SUPERVISION FROM 13 TO 21 YEARS OROLDER: ADOLESCENCE TO EARLY ADULTHOOD

Examination

1. Continue to record growth parameters.2. Review weight control and diet.3. Monitor for any signs or symptoms of nerve com-

pression and check deep tendon reflexes, tone,and sensory findings, if indicated.

4. Continue to assess history for possible obstructivesleep apnea.


1. Check on social adaptation.2. Discuss the diagnosis with the adolescent to be

sure that he or she has the vocabulary and theunderstanding of the genetic nature of achondro-plasia.

3. Discuss contraception. The importance and useof contraception should be discussed with bothmales and females. Women with achondroplasiausually are fertile. Oral contraception should not

be used long-term, because women with achon-droplasia may have an increased risk of uterinefibroids, which may be aggravated by oral con-



12/13

traceptives. However, using a diaphragm is dif-ficult because of the short arms in achondropla-sia. Finding the appropriate long-term contraceptionmay require consultation with a knowledgeablegynecologist. Women with achondroplasia oftendevelop respiratory compromise late in pregnan-cy; thus, baseline respiratory function studies arerecommended early in pregnancy. All pregnantwomen with achondroplasia will require caesar-ian delivery because of their small pelvic outlet.Because of spinal stenosis, spinal anesthesia isnot recommended, and most women with achon-droplasia should have general anesthesia fortheir cesarean delivery. If the partner of thewoman with achondroplasia is of average stat-ure, there will be a 50% risk of the infant havingachondroplasia. If the partner also has short stat-ure, the specific recurrence risk and the possibil-ity of a severely affected infant must be deter-mined so that the pregnancy and neonate can bemanaged properly. Prenatal diagnosis should bediscussed to facilitate the management of thepregnancy for optimal outcome.18

4. Review orthodontic status.5. Continue weight counseling.48,496. Encourage the family and affected person to set

career and life goals high and appropriate, as forother members of the family. Assist in adaptingto an independent life and in obtaining a driverslicense. Drivers usually require a vehicle that isadapted with pedal extenders; extenders that can

be easily mounted and removed as needed areavailable. Families may wish to work with adriver-rehabilitation specialist who is qualifiedto assess the drivers transportation needs andwho can provide them with a list of appropriatevehicle modifications. Names of qualified evalu-

ators can be obtained by contacting a local rehabilitation center or the Association for DriverRehabilitation Specialists (609-844-4433).50 Formost it will be necessary to provide a letter of

justification for disabling of the air bag, becauseeven with pedal extenders, marked arm fore-shortening will preclude positioning at an appro-priate distance from the air bag (10 12 in).47

Individuals who want to have an air bag on-offswitch must read an informational brochure andsubmit an official request to the National High-way Traffic Safety Administration (888-DASH-2-DOT [www.nhtsa.dot.gov]). Approval does not

guarantee, however, that the request will be hon-ored by a vehicle dealer.51

7. Discuss college, vocational planning and train-ing, and other plans after high school.

8. Foster independence.9. Continue to encourage participation in social ac-

tivities and support groups. It is particularly use-ful during this age period.

10. Assist in transition to adult care.

Committee on Genetics, 20032004G. Bradley Schaefer, MD, ChairpersonMarilyn J. Bull, MDJoseph H. Hersh, MD

Celia I. Kaye, MD, PhDNancy J. Mendelsohn, MDJohn B. Moeschler, MDHoward M. Saal, MDChris Cunniff, MD

Past Committee ChairpersonTracy L. Trotter, MD

Past Committee Member

ContributorsJudith G. Hall, OC, MDRichard M. Pauli, MD, PhD

Liaisons James D. Goldberg, MD

American College of Obstetriciansand Gynecologists

James W. Hanson, MDNational Institute of Child Healthand Human DevelopmentAmerican College of MedicalGenetics

Michele Ann Lloyd-Puryear, MD,PhDHealth Resources and ServicesAdministration

Sonja A. Rasmussen, MDCenters for Disease Control andPrevention

StaffPaul Spire

RESOURCES FOR PARENTS

Little People of America, Inc.PO Box 65030Lubbock, TX 79464-5030www.lpaonline.orgParent Coordinators: Grady and Mary Quick4240 Oak Grove Dr

Carrollton, TX 75010

Books and Pamphlets

Kuklin S. Thinking Big: The Story of a Young Dwarf.New York, NY: Lothrop, Lee & Shepard Books; 1986

Campbell J, Dorren N. Its a Whole New View: ABeginners Guide for New Parents of a Child With Dwarf-ism. Lubbock, TX: Little People America Inc; 1998(available without charge from Little People ofAmerica at the address listed above)

To Celebrate: Understanding Developmental Differ-ences in Young Children With Achondroplasia and LittlePeople, Big SchoolsPreparing the School for Your

Young Child With Short Stature. Madison, WI: Mid-west Regional Bone Dysplasia Clinic; 1997 (bothavailable at cost from Midwest Regional Bone Dys-plasia Clinic, University of Wisconsin, 1500 High-land Ave, Madison, WI 53705-2280)

Summary Chapters

Francomano CA. GeneReviews: achondroplasia.Available at: www.genetests.org. Accessed July 16,2003

Pauli RM. Achondroplasia. In: Cassidy SB, Allan-son JE, eds. Management of Genetic Syndromes. NewYork, NY: Wiley-Liss; 2001:932



13/13

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All clinical reports from the American Academy of Pediatricsautomatically expire 5 years after publication unlessreaffirmed, revised, or retired at or before that time.


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