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Home , Achondroplasia, Thanatophoric dysplasia

AMERICAN ACADEMY OF PEDIATRICS

CLINICAL REPORT Guidance 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

ABSTRACT. Achondroplasia is the most common con- radiographs, which include contracted base of the dition associated with disproportionate . skull, square shape of the pelvis with a small sacro- Substantial information is available concerning the nat- sciatic notch, short pedicles of the vertebrae, rhi- ural history and anticipatory health supervision needs in zomelic (proximal) shortening of the long bones, tri- children with this dwarfing disorder. Most children with dent hands, a normal-length trunk, proximal femoral achondroplasia have delayed motor milestones, prob- lems with persistent or recurrent middle-ear dysfunction, radiolucency, and (by midchildhood) a characteristic and bowing of the lower legs. Less often, infants and chevron shape of the distal femoral . Other children may have serious health consequences related to rhizomelic dwarfing disorders such as hypochondro- , craniocervical junction compression, up- plasia and are part of the per-airway obstruction, or thoracolumbar . An- , but achondroplasia usually ticipatory care should be directed at identifying children can be distinguished from them because the changes who are at high risk and intervening to prevent serious in are milder and the changes in sequelae. This report is designed to help the pediatrician thanatophoric dysplasia are much more severe and care for children with achondroplasia and their families. invariably lethal. Achondroplasia is an autosomal Pediatrics 2005;116:771–783; achondroplasia, short stat- dominant disorder, but approximately 75% of cases ure, children, health supervision. represent new dominant . Achondroplasia is caused by in the that codes for the ABBREVIATIONS. OFC, occipital-frontal circumference; CT, com- fibroblast type 3 (FGFR3).5–7 puted tomography. Because virtually all of the causal mutations occur at exactly the same place within the gene,7 molecular INTRODUCTION testing is straightforward. It is not necessary to per- his clinical report is designed to assist the pe- form molecular testing in every child with a clinical diatrician in caring for children with achondro- diagnosis of achondroplasia. However, FGFR3 test- Tplasia confirmed by radiographs and physical ing should be performed in children who are in any features. Although pediatricians usually first see way atypical or in circumstances in which differen- children with achondroplasia during infancy, occa- tiation from similar disorders, such as hypochondro- sionally they are called on to advise a pregnant plasia, is not certain. Such children also should be woman who has been informed of the prenatal di- referred for clinical genetic evaluation. agnosis of achondroplasia or asked to examine a A great deal is known about the natural history of newborn to help establish the diagnosis. Therefore, achondroplasia that can be shared with the family.3,8 this report offers advice for these situations as well. The average adult height in achondroplasia is ap- Substantial new information has appeared since proximately 4 ft for men and women (Figs 1 and 2).9 publication of the first policy statement on health 1 The most common , occurring in adult- supervision of children with achondroplasia. In par- hood, is related to lumbosacral with ticular, a great deal has been learned about the mo- 10,11 2 compression of the spinal cord or nerve roots. lecular genetics of the disorder. In addition, a more This complication is usually treatable by surgical complete understanding of how certain serious com- 3 decompression if it is diagnosed at an early stage. plications can be minimized or avoided has accrued. Most children with achondroplasia do well. How- The new information is incorporated into this report, ever, children affected with achondroplasia com- which is a revision of the original policy statement. monly have delayed motor milestones (Fig 3),12,13 Achondroplasia is the most common condition as- 14 4 media, and bowing of the lower legs. Less sociated with severe disproportionate short stature. commonly, infants and children may have serious The diagnosis can usually be made on the basis of health consequences related to hydrocephalus, clinical characteristics and very specific features on craniocervical junction compression, upper-airway obstruction, or thoracolumbar kyphosis. Although The guidance in this report does not indicate an exclusive course of treat- they are less common, anticipatory care should be ment or serve as a standard of medical care. Variations, taking into account directed at identifying children who are at high risk individual circumstances, may be appropriate. doi:10.1542/peds.2005-1440 and intervening to prevent serious sequelae. Most PEDIATRICS (ISSN 0031 4005). Copyright © 2005 by the American Acad- individuals with achondroplasia are of normal intel- emy of Pediatrics. ligence and are able to lead independent and pro-

Downloaded from www.aappublications.org/news byPEDIATRICS guest on September Vol. 26, 116 2021 No. 3 September 2005 771 Fig 1. Height for males with achondroplasia (mean Ϯ 2.8 standard deviation) compared with normal standard curves. The graph was derived from 189 males. (Reproduced with permission from J Pediatr. 1978;93:435-438.)

ductive lives.15 Because of their disproportionate must be tailored to a particular child’s condition and short stature, however, a number of psychosocial needs. problems can arise. Families can benefit from antic- ipatory guidance and the opportunity to learn from THE PRENATAL VISIT other families with children of disproportionate Pediatricians may be called on to counsel expect- short stature. ant parents whose fetus has achondroplasia or is The consensus-based guidance in this report is suspected to have achondroplasia because of recog- designed to help the pediatrician care for children nition on ultrasonography of disproportionate small with achondroplasia and their families. Issues that stature. In some settings, the pediatrician will be the need to be addressed at various ages are discussed primary resource for counseling a family. At other (Table 1). These suggestions are not appropriate for times, counseling may already have been provided other chondrodysplasias, because each type has its to the family by a clinical geneticist and/or the ob- own natural history, complications, and specific stetrician. Because of a previous relationship with the guidelines. Irrespective of the availability of the family, however, the pediatrician may be called on to guidance in this report, it is important that pediatri- review this information and assist the family in the cians and parents also consult a physician with spe- decision-making process. cial experience and expertise concerning achondro- The diagnosis of achondroplasia in the fetus is plasia early in the child’s life, because this report made most often with certainty when 1 or both par- only provides generally applicable suggestions that ents have this condition. In this circumstance, the

772 HEALTH SUPERVISIONDownloaded FOR from CHILDREN www.aappublications.org/news WITH ACHONDROPLASIA by guest on September 26, 2021 Fig 2. Height for females with achondroplasia (mean Ϯ 2.8 standard deviation) compared with normal standard curves. The graph was derived from 214 females. (Reproduced with permission from J Pediatr. 1978;93:435-438.)

parents are usually knowledgeable about the disor- trician should also discuss the natural history of der, the inheritance, and the prognosis for the off- achondroplasia, because it is the most likely expla- spring. More often, diagnosis of achondroplasia is nation for the findings. In cases in which the diag- first suspected late in gestation on the basis of long- nosis is unequivocally established either because of bone foreshortening incidentally discovered by ul- the familial nature of the disorder or by prenatal trasonography. With the frequent use of ultrasonog- molecular diagnosis (chorionic villus sampling at raphy, many cases of achondroplasia are first 11–13 weeks’ gestation or amniocentesis after 15 identified prenatally (after 26 weeks of gestational weeks’ gestation), the pediatrician may consider the age). However, disproportionately short limbs are following steps as appropriate. observed in a heterogeneous group of conditions. Misdiagnosis and inaccurate prenatal counseling of 1. Review, confirm, and demonstrate laboratory or families is common.16 Confirmation of diagnosis imaging studies leading to the diagnosis. based on ultrasonographic features characteristic of 2. Explain the mechanisms for occurrence of achon- achondroplasia can be provided by molecular testing droplasia in the fetus and the recurrence risk for (FGFR3 mutational testing) of prenatal specimens. If the family. no such confirmation has yet been completed, cau- 3. Remember that at least 75% of cases of achondro- tion should be exercised when counseling the family. plasia occur in families in which both parents In this circumstance, the pediatrician should discuss have average stature. In those cases, achondropla- the tentative nature of the diagnosis and alternatives sia in the offspring occurs because of a mutation that may explain the identified features. The pedia- in the gene.

Downloaded from www.aappublications.org/news by AMERICANguest on September ACADEMY 26, 2021 OF PEDIATRICS 773 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 from 197 affected individuals, obtained by questionnaire. (Reproduced with permission from Am J Med Genet. 1981;9:19-23.)

4. Review the natural history and manifestations of with ultrasonographic measurements at 14, 16, 18, achondroplasia, including variability.3 22, and 32 weeks of gestation to distinguish ho- 5. Discuss additional studies that should be per- mozygosity or heterozygosity from normal growth formed, particularly those to confirm the diagno- patterns in the fetus. sis in the newborn period. If miscarriage, still- 9. When both parents are of disproportionate short birth, or termination occurs, confirmation of stature, assess the possibility of double het- diagnosis is important for counseling family erozygosity19 or homozygosity for achondropla- members about recurrence. sia. Some forms of double heterozygosity lead to 6. Review currently available treatments and inter- life-threatening problems19; infants with homozy- ventions. This discussion needs to include the ef- gous achondroplasia usually are stillborn or die ficacy, complications, adverse effects, costs, and shortly after birth.20 other burdens of these treatments. Discuss possi- ble future treatments and interventions. 7. Explore the options available to the family for the HEALTH SUPERVISION FROM BIRTH TO management and rearing of the child using a non- 1 MONTH OF AGE: NEWBORNS directive approach. In cases of early prenatal di- Examination agnosis, these options may include discussion of pregnancy termination, continuation of preg- 1. Confirm the diagnosis by radiographic studies nancy and rearing of the child at home, foster care, (the diagnosis of approximately 20% of patients or adoption. If adoption is planned to another family, contact may be made with the Little Peo- with achondroplasia has been delayed in the past ple of America adoption service.17 because it was not suspected on physical exami- 8. If the mother is affected with achondroplasia, in- nation in the newborn period, and consequently, form her that a cesarean delivery must be per- no radiographs were obtained). formed because of the characteristic small pel- 2. Document measurements, including occipital- vis.18 A mother affected with achondroplasia may frontal circumference (OFC), body length, and develop respiratory compromise during the third body weight; plot these measurements on achon- trimester of pregnancy, so baseline pulmonary droplasia-specific growth charts (Figs 1, 2, and function studies should be performed. Homozy- 4–7). Review the phenotype with the parents and gous achondroplasia can be diagnosed prenatally discuss the specific findings with both parents with molecular testing of the fetus, by either cho- whenever possible. rionic villus sampling or amniocentesis. A preg- 3. The OFC should be measured at every pediatric nancy at risk of homozygosity should be followed contact during the first year (Figs 4 and 5).

774 HEALTH SUPERVISIONDownloaded FOR from CHILDREN www.aappublications.org/news WITH ACHONDROPLASIA by guest on September 26, 2021 TABLE 1. Achondroplasia Guidelines for Health Supervision Prenatal Infancy, 1 mo to1yofAge Early Childhood, 1 to5yofAge Late Childhood Adolescence Neonatal 2 mo 4 6 9 12 15 18 24 3 4 y 5 to 13 y, Annual 13 to 21 y, Annual mo mo mo mo mo mo mo y Downloaded from Diagnosis Whenever the diagnosis is suspected Review phenotype Whenever the diagnosis is suspected Review proportions Whenever the diagnosis is suspected Molecular testing ͓FGFR3͔ See text When diagnosis is not certain Genetic counseling www.aappublications.org/news Early intervention X Recurrence risks X X X Reproductive options XXX Family support X X X X X Support groups X X X X X Long-term planning XX XX Medical evaluation Growth/weight/OFC X X XXXXX X X X X Orthopedic consult Neurology consult Hearing XR XR XR XR byguestonSeptember 26,2021 Social readiness SSSS

MRCNAAEYO PEDIATRICS OF ACADEMY AMERICAN Orthodontics RR R Speech S/O S/O S/O S/O O O Medical evaluation Radiography, only to make diagnosis or if complication CT/MRI brain/cervical X spine Polysomnography X As indicated 333333333 3 3 Social adjustment Psychosocial SS S SS Behavior and development S/O S/O S/O S/O S/O S/O S/O S/O S/O S/O School OOO Sexuality X These guidelines ensure compliance with AAP recommendations for preventive pediatric health care. FGFR3 indicates fibroblast growth factor receptor type 3; X, to be performed; S, subjective, by history; O, objective, by a standard testing method; R, discuss referral to a specialist; 3, continue to monitor. 775 Fig 4. Head circumference for males with achondro- plasia compared with normal curves (dashed lines). The graph was derived from 189 males. (Reproduced with permission from J Pediatr. 1978;93:435-438.)

Anticipatory Guidance significantly increasing stature. Growth-hor- mone therapy may result in a transient increase 1. Discuss the specific findings of achondroplasia in growth rate. However, the salutary effects with the parents, including the following: diminish with continued treatment. No study • Autosomal dominant inheritance: approxi- has clearly demonstrated a significant benefit mately 75% of cases are new mutations. Germ- with respect to ultimate adult stature.24,25 If line mosaicism (in which some germ cells are elected, such treatment should be considered derived from a normal cell line and some are only within a research setting. Extended limb from a cell line with a mutation) has been re- lengthening using a variety of techniques has ported, but the risk of recurrence in sporadic been used far more elsewhere than in North cases is less than 1%.21–23 America. It can result in substantial increases in • Most individuals with achondroplasia have nor- ultimate height.26,27 However, it is arduous, not mal intelligence and normal life expectancy. without risk, and costly. Most families alterna- • Although serious problems may arise during tively choose to modify the environment to ac- infancy, such problems affect only 5% to 10% of commodate the child rather than the converse. infants with achondroplasia. • Special achondroplasia growth curves and in- • Growth hormones, other drug therapies, and fant development charts have been developed food or vitamin supplements are not effective in (Figs 1–7); the final expected adult height for

776 HEALTH SUPERVISIONDownloaded FOR from CHILDREN www.aappublications.org/news WITH ACHONDROPLASIA by guest on September 26, 2021 Fig 5. Head circumference for females with achondro- plasia compared with normal curves (dashed lines). Data were derived from 145 females. (Reproduced with permission from J Pediatr. 1978;93:435-438.)

persons with achondroplasia is approximately 4 slings to limit uncontrolled head movement ft.9 around the small foramen magnum. There are 2. Discuss the following possible severe medical instances in which infants with achondroplasia complications and methods of prevention: who showed no clinical abnormality by exami- • Unexpected infant death occurs, in the absence nation and who were asymptomatic have died of aggressive evaluation, in approximately 2% to from this complication. Given this, and because 5% of all infants with achondroplasia.28,29 This it can be life saving, care of every infant with seems to result from central arising sec- achondroplasia should include assessment for ondary to compression of arteries at the level of craniocervical junction risks, which includes the foramen magnum.28 In addition, the univer- careful neurologic history and examination, sally small foramen magnum may result in a neuroimaging, and polysomnography.31 Neuro- high cervical myelopathy.30,31 However, with imaging can be by computed tomography (CT) appropriate assessment and intervention, both with thin cuts and bone windows31 or magnetic risks can be minimized.31 Parents should be ad- resonance imaging (MRI),32,33 each of which has vised to use an infant seat or infant carrier that benefits and disadvantages: CT allows direct has a firm back that supports the neck and to use comparison of foramen magnum size with pub- a rear-facing car safety seat for as long as possi- lished achondroplasia standards and often can ble. They should be counseled to avoid use of be accomplished without sedation or anesthesia products like mechanical swings and carrying but does not allow direct visualization of the

Downloaded from www.aappublications.org/news by AMERICANguest on September ACADEMY 26, 2021 OF PEDIATRICS 777 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.)

neural elements of interest; MRI provides such a • If severe problems are found (eg, marked abnor- direct assessment of the brainstem and upper mality by neurologic examination, such as pro- cervical spinal cord, but no standards for esti- found or sustained ankle clonus; mation of foraminal size by MRI are available, markedly diminished foramen magnum size and currently it cannot be performed routinely compared with achondroplasia standard; sub- without sedation. Rapid development of imag- stantial deformation of the upper cervical spinal ing technology suggests that alternative meth- cord; hypoxemic episodes with minimal oxygen ods may become appropriate in the future. saturations below 85%31), referral to a neurosur-

778 HEALTH SUPERVISIONDownloaded FOR from CHILDREN www.aappublications.org/news WITH ACHONDROPLASIA by guest on September 26, 2021 geon or other physician skilled and experienced ondary to constriction of the foramen mag- in the care and treatment of neurologic prob- num. lems in children with achondroplasia should be (b) Care should be taken to ensure that medica- initiated.34 tion dosages are appropriate for size. • Hydrocephalus is a lifelong risk but is most (c) Access to veins is sometimes difficult be- likely to develop during the first 2 years.35 OFC cause of lack of full extension at the elbow. should be monitored carefully during this time. (d) Generally, spinal anesthesia should be If the OFC is large or crosses percentiles on the avoided, particularly when there is kyphosis achondroplasia-specific head-circumference chart, or severe lumbar , because of limited it is appropriate to refer the infant to a pediatric space within the spinal canal. neurologist or pediatric neurosurgeon. Baseline (e) General anesthesia should be strongly con- CT or MRI (performed in conjunction with im- sidered for cesarean delivery for pregnant aging of the craniocervical junction) is valuable women with achondroplasia (they will all if there is concern about possible hydrocepha- require caesarian delivery because of con- lus. Repeating neuroimaging to assess change in tracted pelves), because use of epidural an- ventricular size should be considered if there is esthesia in these women requires special skill acceleration of head growth compared with and expertise.40/P achondroplasia standards or if other signs like 3. Discuss the potential psychosocial implications bulging, hard , or symptoms of un- for both parent and child related to disproportion- usual lethargy or intractable irritability develop. ate short stature. Refer the affected individual or Both ventriculomegaly and excessive extra-axial the parent of an affected individual to a support fluid are common benign accompaniments of group such as Little People of America (also see achondroplasia35 and should not be misinter- “Resources for New Parents”). If parents do not preted as indicative of need for shunt place- wish to join a group, they may want to meet with ment. Neural ultrasonography may be used to or talk to other affected individuals or parents. follow these clinical findings. Remind parents that most individuals with achon- • Restrictive pulmonary disease occurs in less droplasia lead productive, independent lives. than 5% of children with achondroplasia who 4. Discuss with the parents how to tell their family are younger than 3 years.36 Living at high ele- and friends about their child’s growth problem. vation markedly increases the risk that restric- 5. Supply the parents with educational books and tive problems will develop. If there are signs of pamphlets (see “Resources for New Parents”). respiratory distress or evidence of poor weight 6. Discuss the realistic functional problems for af- gain despite adequate caloric intake, pulse fected individuals. oximetry (during feeding, when crying, and at 7. Discuss individual resources for support, such as rest) should be considered to monitor oxygen- family, clergy, social workers, psychologists, and ation. friends. • Most infants with achondroplasia develop a tho- 8. Review the prenatal diagnosis and recurrence racolumbar kyphosis. More severe kyphosis is risks for subsequent pregnancies. associated with unsupported sitting before there is adequate trunk muscle strength.37,38 Parents HEALTH SUPERVISION FROM 1 MONTH TO should be counseled to avoid unsupported sit- 1 YEAR OF AGE: INFANCY ting and to avoid devices that cause curved sit- Examination ting or “C sitting,” such as “umbrella-style” 1. For infants not diagnosed in the newborn period, strollers and soft canvas seats during the first arrange for neuroimaging and polysomnography year of life. Use of feeder seats for upright po- at the time of diagnosis. sitioning should be recommended. If severe ky- 2. Assess growth and development in comparison phosis appears to be developing, consider a pe- only with children with achondroplasia (Figs 1–7). diatric orthopedic surgical assessment to 3. Perform physical examination. determine if bracing is needed.38 4. Review head growth on achondroplasia-specific • The common complication of spinal stenosis head-circumference charts. rarely occurs in childhood but manifests in older 5. Refer the infant to a pediatric neurologist or pe- individuals with numbness, weakness, and al- diatric neurosurgeon if head size is disproportion- tered deep tendon reflexes.30 Severe thoraco- ately large or crosses percentiles, if there are signs lumbar kyphosis is one mechanism that can give or symptoms of hydrocephalus, or if there are rise to spinal stenosis. It is for this reason that indicators of possible craniocervical junction com- unsupported sitting before there is adequate pression, including excessively brisk reflexes, trunk muscle strength is discouraged. asymmetric reflexes, ankle clonus, extreme hypo- • Anesthesia risk:39 if an individual with achon- tonia, or early hand preference.10,35 droplasia needs to have anesthesia and surgery, 6. Consider repeating neuroimaging studies if there the following should be considered: is acceleration of head growth, severe persisting (a) Care must be taken in manipulation of the hypotonia, or any signs of craniocervical junction neck, because uncontrolled neck movement compression.31–34 Growth of the foramen mag- (as may occur with intubation) could lead to num may be compared with achondroplasia-spe- unintentional spinal cord compression sec- cific standards.41

Downloaded from www.aappublications.org/news by AMERICANguest on September ACADEMY 26, 2021 OF PEDIATRICS 779 7. Check motor development and discuss develop- bear weight. Lumbar lordosis usually develops ment; note on the milestone charts for achondro- but rarely requires specific intervention. Weight plasia. Expect motor delay but not social or cog- bearing and walking may occur late; however, nitive delay.12,13 Check for serous . they are expected by 2 to 2.5 years of age. When Review risk at 6 to 12 months of age. Formal weight bearing begins, the external rotation of behavioral audiometric assessment should be the hips should self-correct to a normal orienta- completed at 9 to 12 months of age. Language tion within 6 months. delay may be present secondary to conductive 4. Anticipate some bowing of the legs. Many chil- hearing loss. dren will also have instability of the soft tissues 8. Continue to monitor for progression of kyphosis surrounding the knee and internal tibial torsion. at the thoracolumbar junction. It is recommended If positional deformity and instability leads to that parents avoid carrying a child with achondro- difficulty walking, a thrust at the knee (uncon- plasia in curled-up (C-sitting) positions. Certain trolled lateral or medial movement with weight types of child carriers, mechanical swings, jump- bearing), or chronic pain, consult a pediatric or- ers, and umbrella-style strollers tend to increase thopedist.14 risk for gibbus. Unsupported sitting should be 5. Check the child’s hips for hip-flexion contrac- 37,38 avoided. Parents and therapists should be in- tures. Prescribe exercises that may decrease lum- structed to provide back support during the first bar lordosis and hip-flexion contractures if indi- year of life. If severe kyphosis appears to be de- cated. Check the hips for external rotation. Refer veloping, consider pediatric orthopedic surgical 38 the child to a pediatric orthopedist if necessary. assessment to determine if bracing is needed. 6. Screen hearing each year. If otologic history, 9. Be aware that external rotation of the hips is com- hearing screening, or speech development raise monly present and usually disappears spontane- concerns about hearing, formal audiologic as- ously when the child begins to bear weight. This sessment should be obtained. finding does not require bracing for the infant. 7. Perform speech evaluation at no later than 2 years of age. If speech is delayed, conductive Anticipatory Guidance hearing loss attributable to chronic serous otitis 1. Review the personal support available to the fam- media should be excluded. ily. 8. Watch for obstructive secondary to 2. Review contact with support groups. smaller-than-average airway size plus physio- 3. Observe the emotional status of parents and in- logic adenoidal hypertrophy.42–44 Most children trafamily relationships. with achondroplasia snore. However, if obstruc- 4. Discuss early-intervention services and the impor- tive apnea or disordered breathing in sleep is tance of normal socializing experiences with other suspected (increased retraction, glottal stops, children. choking, intermittent breathing, apnea, deep 5. Ask the parents whether they have educated their compensatory sighs, secondary enuresis, recur- family members about achondroplasia; discuss rent night-time awakening or emesis), then ad- sibling adjustment. ditional pulmonary evaluation and polysomnog- 6. Review the increased risk of serous otitis media raphy are indicated. because of short eustachian tubes. Indicate that an 9. Be aware that gastroesophageal reflux may be ear examination is appropriate with any persistent more common in children with achondroplasia or severe upper respiratory tract infection or when and may be more common in those with neuro- parents suspect that ear pain may be present. respiratory complications.45 If reflux is severe, in 7. Advise parents to avoid infant carriers that curl addition to usual treatments, consider referral to up the infant. This does not apply to car safety a pediatric specialist with experience in treating seats, which should always be used during auto- gastroesophageal reflux in infants and children. mobile travel. A rear-facing car safety seat should 10. Do not misinterpret greater-than-average sweat- be used to the highest weight allowed by a con- vertible seat (25–30 lb). ing as indicative of serious medical problems; it 8. Discuss filing for Supplemental Security Income is normal in children with achondroplasia. benefits as appropriate. 11. In rare instances in which diagnosis of achondro- plasia is delayed beyond 1 year of age, determine if neuroimaging is needed on the basis of clinical HEALTH SUPERVISION FROM 1 TO 5 YEARS OF . AGE: EARLY CHILDHOOD Examination 1. Assess the child’s growth and development as Anticipatory Guidance plotted on the achondroplasia growth charts. 1. Consider adapting the home so that the child can 2. Continue to follow rate of head growth on the become independent (eg, lower the light switches, achondroplasia-specific head-circumference charts. use lever door handles and lever sink faucets, make 3. Continue to watch for thoracolumbar gibbus (ky- the toilet accessible, and supply step stools) (see phosis). Discuss avoiding the use of walkers, “Resources for Parents”). jumpers, or backpack carriers. Any kyphosis 2. Determine if an occupational therapy consulta- present should disappear as the child begins to tion is needed.

780 HEALTH SUPERVISIONDownloaded FOR from CHILDREN www.aappublications.org/news WITH ACHONDROPLASIA by guest on September 26, 2021 3. Discuss adapting age-appropriate clothing with 2. Discuss preparation of the school and teacher for snapless, easy-opening fasteners and tuckable a child with short stature (see “Resources for loops. Parents”). 4. Discuss adaptation of toys, especially tricycles, to 3. Prepare the child for others’ questions and curi- accommodate short limbs. osity. Be sure the child can explain why he or she 5. Discuss adaptation of toilets to allow comfort- is short and can ask for help in an appropriate able, independent use, with an extended wand way. Children with achondroplasia usually are for wiping if needed. included in the regular education program. 6. Discuss the use of a stool during sitting so that 4. Suggest adaptive aids for the school to cope with the child’s feet are not hanging. Feet need sup- heavy doors, high doorknobs, reaching for the port while the child is sitting at a desk, in a chair, blackboard, foot support, and a regular-sized or on the toilet. A cushion behind the child’s back desk. Also, be sure that the child can use the may be required for good posture and to prevent restroom independently (see “Resources for Par- chronic . Counsel parents for optimal ents”). protection to use a convertible rear-facing car 5. Counsel parents to use a child safety seat with a safety seat to the highest weight and height al- full harness to the highest weight allowed by the lowed by the manufacturer of the seat.46 A rear- manufacturer of the seat and then to transition to facing seat provides the best support protection the belt-positioning booster seat for optimal seat- and positioning angle for a child with macro- belt positioning.46 cephaly and skeletal dysplasia. Parents may ben- 6. Review socialization and foster independence. efit from suggestions for behavioral intervention 7. Discuss contact with support groups. They are to promote continuing the rear-facing position as especially valuable at this age. long as possible.47 8. Consider obtaining an orthopedic evaluation 7. Review weight control and eating habits to avoid when the child is approximately 5 years of age to , which often becomes a problem in mid- make appropriate treatment plans if necessary. to late childhood.48 9. Emphasize correct posture and encourage the 8. Discuss orthodontic bracing in the future and the child to consciously decrease lumbar lordosis by possible need for early orthodontic assessment to “tucking the buttocks under.” If lordosis is se- consider palatal expansion. vere, consider physical therapy referral to teach 9. Encourage the family to develop activities in lower abdominal muscle strengthening and pel- which the child can take part; avoid gymnastics, vic rotation. diving, trampolines, and collision sports. 10. Develop an activity program with acceptable ac- 10. Discuss how to talk with the child and friends or tivities such as swimming and biking. The child family members about short stature. should avoid gymnastics and collision sports be- 11. Encourage preschool attendance so that the child cause of the potential for neurologic complica- can learn to socialize in an age-appropriate way, tions secondary to cervical spinal stenosis. If soc- and work with parents to prepare the teacher cer is played, heading should be prohibited. and the other children so that the child is not 11. Review orthodontic and speech status. given unnecessary special privileges. 12. Discuss toileting at school and special prepara- HEALTH SUPERVISION FROM 13 TO 21 YEARS OR tions needed by the school because of the child’s OLDER: ADOLESCENCE TO EARLY ADULTHOOD short stature (see “Resources for Parents”). Examination 1. Continue to record growth parameters. HEALTH SUPERVISION FROM 5 TO 13 YEARS 2. Review weight control and diet. OF AGE: LATE CHILDHOOD 3. Monitor for any signs or symptoms of nerve com- Examination pression and check deep tendon reflexes, tone, 1. Assess and review the child’s growth, develop- and sensory findings, if indicated. ment, and social adaptation. 4. Continue to assess history for possible obstructive 2. Plot measures on achondroplasia weight-by- sleep apnea. height grids (Figs 6 and 7). 3. Review weight control.48 The child may need to Anticipatory Guidance restrict food intake and eat less than an average- 1. Check on social adaptation. sized child eats. 2. Discuss the diagnosis with the adolescent to be 4. Complete a general and neurologically oriented sure that he or she has the vocabulary and the physical examination. understanding of the genetic nature of achondro- 5. Check deep tendon reflexes yearly for asymmetry plasia. or increased reflexes that suggest spinal stenosis. 3. Discuss contraception. The importance and use 6. Continue to assess history for possible obstructive of contraception should be discussed with both sleep apnea. males and females. Women with achondroplasia 7. Test hearing each year. usually are fertile. Oral contraception should not be used long-term, because women with achon- Anticipatory Guidance droplasia may have an increased risk of uterine 1. Determine school readiness. fibroids, which may be aggravated by oral con-

Downloaded from www.aappublications.org/news by AMERICANguest on September ACADEMY 26, 2021 OF PEDIATRICS 781 traceptives. However, using a diaphragm is dif- Celia I. Kaye, MD, PhD ficult because of the short arms in achondropla- Nancy J. Mendelsohn, MD sia. Finding the appropriate long-term contraception John B. Moeschler, MD may require consultation with a knowledgeable Howard M. Saal, MD gynecologist. Women with achondroplasia often Chris Cunniff, MD Past Committee Chairperson develop respiratory compromise late in pregnan- Tracy L. Trotter, MD cy; thus, baseline respiratory function studies are Past Committee Member recommended early in pregnancy. All pregnant women with achondroplasia will require caesar- Contributors ian delivery because of their small pelvic outlet. Judith G. Hall, OC, MD Because of spinal stenosis, spinal anesthesia is Richard M. Pauli, MD, PhD not recommended, and most women with achon- droplasia should have general anesthesia for Liaisons their cesarean delivery. If the partner of the James D. Goldberg, MD woman with achondroplasia is of average stat- American College of Obstetricians ure, there will be a 50% risk of the infant having and Gynecologists James W. Hanson, MD achondroplasia. If the partner also has short stat- National Institute of Child Health ure, the specific recurrence risk and the possibil- and Human Development ity of a severely affected infant must be deter- American College of Medical mined so that the pregnancy and neonate can be Genetics managed properly. Prenatal diagnosis should be Michele Ann Lloyd-Puryear, MD, discussed to facilitate the management of the PhD pregnancy for optimal outcome.18 Health Resources and Services 4. Review orthodontic status. Administration 5. Continue weight counseling.48,49 Sonja A. Rasmussen, MD Centers for Disease Control and 6. Encourage the family and affected person to set Prevention career and life goals high and appropriate, as for other members of the family. Assist in adapting Staff to an independent life and in obtaining a driver’s Paul Spire license. Drivers usually require a vehicle that is adapted with pedal extenders; extenders that can RESOURCES FOR PARENTS be easily mounted and removed as needed are Little People of America, Inc. available. Families may wish to work with a PO Box 65030 driver-rehabilitation specialist who is qualified Lubbock, TX 79464-5030 to assess the driver’s transportation needs and www.lpaonline.org who can provide them with a list of appropriate Parent Coordinators: Grady and Mary Quick vehicle modifications. Names of qualified evalu- 4240 Oak Grove Dr ators can be obtained by contacting a local reha- Carrollton, TX 75010 bilitation center or the Association for Driver Rehabilitation Specialists (609-844-4433).50 For Books and Pamphlets most it will be necessary to provide a letter of Kuklin S. Thinking Big: The Story of a Young Dwarf. justification for disabling of the air bag, because New York, NY: Lothrop, Lee & Shepard Books; 1986 even with pedal extenders, marked arm fore- Campbell J, Dorren N. It’s a Whole New View: A shortening will preclude positioning at an appro- Beginner’s Guide for New Parents of a Child With Dwarf- 47 priate distance from the air bag (10–12 in). ism. Lubbock, TX: Little People America Inc; 1998 Individuals who want to have an air bag on-off (available without charge from Little People of switch must read an informational brochure and America at the address listed above) submit an official request to the National High- To Celebrate: Understanding Developmental Differ- way Traffic Safety Administration (888-DASH-2- ences in Young Children With Achondroplasia and Little DOT [www.nhtsa.dot.gov]). Approval does not People, Big Schools—Preparing the School for Your guarantee, however, that the request will be hon- Young Child With Short Stature. Madison, WI: Mid- ored by a vehicle dealer.51 west Regional Bone Dysplasia Clinic; 1997 (both 7. Discuss college, vocational planning and train- available at cost from Midwest Regional Bone Dys- ing, and other plans after high school. plasia Clinic, University of Wisconsin, 1500 High- 8. Foster independence. land Ave, Madison, WI 53705-2280) 9. Continue to encourage participation in social ac- tivities and support groups. It is particularly use- Summary Chapters ful during this age period. Francomano CA. GeneReviews: achondroplasia. 10. Assist in transition to adult care. Available at: www.genetests.org. Accessed July 16, Committee on Genetics, 2003–2004 2003 G. Bradley Schaefer, MD, Chairperson Pauli RM. Achondroplasia. In: Cassidy SB, Allan- Marilyn J. Bull, MD son JE, eds. Management of Genetic Syndromes. New Joseph H. Hersh, MD York, NY: Wiley-Liss; 2001:9–32

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