Functional Health Status of AdultsWith Achondroplasia

Nizar N. Mahomed,1 Mark Spellmann,2 and Michael J. Goldberg3*1Robert Brigham Multipurpose Arthritis and Musculoskeletal Diseases Center, Department of Orthopaedics, Brighamand Women’s Hospital, Harvard Medical School, Boston, Massachusetts

2School of Social Work, New York University, New York, New York3Department of Orthopaedics, Tufts University, School of Medicine, New England Medical Center,Boston, Massachusetts

Little is known regarding the functionalhealth status of individuals with achondro-plasia. This cross-sectional survey of adultswith achondroplasia was undertaken to as-sess the functional health status of thispopulation and its determinants. The studysample consisted of members of the LittlePeople of America (LPA) who completed amailed questionnaire consisting of a demo-graphics component, a general and disease-specific comorbidities component, and theShort Form 36 (SF-36) health status ques-tionnaire. Univariate analyses and multi-variate linear regression models were usedfor data analysis. Four hundred thirty-seven individuals with a mean age of 38years completed the survey. The age- andgender-adjusted Mental Component Sum-mary (MCS) scores did not significantly dif-fer from those of the general population. Incontrast, the age- and gender-adjustedPhysical Component Summary (PCS) scoreswere significantly lower than the generalpopulation starting in the fourth decade oflife. Musculoskeletal diseases were mostprevalent and had the greatest impact onthe PCS scores. Two-thirds of this cohorthad undergone at least one operation. Onlymusculoskeletal procedures were signifi-cantly associated with PCS and MCS scores.The functional health status of adults with

achondroplasia, as measured by the SF-36,is not drastically reduced in comparisonwith that of the general U.S. population. Am.J. Med. Genet. 78:30–35, 1998.© 1998 Wiley-Liss, Inc.

KEY WORDS: achondroplasia; adults; func-tional health status; cross-sectional survey; SF-36

INTRODUCTION

Achondroplasia is the most frequent short-limb skel-etal dysplasia. It results from a point mutation in thefibroblast growth factor receptor 3 gene located at thetip of the short arm of chromosome 4, causing a singleamino acid change in the transmembrane portion ofthis cell surface receptor [Francomano, 1995; Rousseauet al., 1994; Shiang et al., 1994]. Achondroplasia is anautosomal dominant disorder, with 80–90% of casesbeing spontaneous mutations. The incidence of this dis-order has been estimated to be between 1/26,000 and1/35,000 [Gardner, 1977; Oberklaid et al., 1979]. Thephenotype comprises rhizomelic limb shortness; rela-tively long narrow trunk compared with limbs; en-larged head with frontal bossing; depressed nasalbridge; midface hypoplasia; and short, broad handswith a trident configuration. Frequently associatedmusculoskeletal anomalies include thoracolumbar ky-phosis, lumbar spinal stenosis, foramen magnum ste-nosis, bowed legs, radial head subluxation, hypotonia,and ligament laxity [Aryanpur et al., 1990; Kahanovitzet al., 1982; Morgan and Young, 1980; Pauli et al.,1995; Reid et al., 1987; Rimoin, 1995]. Intelligence isunaffected by the basic defect. Occult hydrocephalusmay be present in childhood. Foramen magnum steno-sis may lead to neurological symptoms that includesleep apnea, marked hypotonia, and delayed mile-stones compromise [Hecht and Butler, 1990; Reid et al.,1987]. In adults, lumbar spinal stenosis leads to caudaequina syndrome of varying degrees of severity. Short,small eustachian tubes lead to an increased incidence

Contract grant sponsor: Pratt Orthopaedics, New EnglandMedical Center, Boston, MA; Contract grant sponsor: AllenGreenberg Skeletal Dysplasia Foundation, Johns Hopkins Hos-pital, Baltimore, MD; Contract grant sponsor: Canadian ArthritisSociety; Contract grant number: 95035; Contract grant sponsor:Academy of Orthopaedic Surgeons of America; Contract grantsponsor: The Orthopaedic Research and Education Foundation.

*Correspondence to: Michael J. Goldberg, M.D., Department ofOrthopaedics, New England Medical Center, 750 WashingtonStreet, No. 202, Boston, MA 02111.

Received 8 April 1997; Accepted 31 July 1997

American Journal of Medical Genetics 78:30–35 (1998)

© 1998 Wiley-Liss, Inc.

of otitis media and hearing problems [Brinkmann etal., 1993].

Most clinical research to date has focused on describ-ing the pathological states associated with achondro-plasia. Little emphasis has been placed on determiningthe general health status of individuals with this ge-netic disorder [Brust et al., 1976; Hecht et al., 1987;Scott, 1977]. This cross-sectional survey was under-taken to assess the functional health status of nonhos-pitalized adults with achondroplasia who were mem-bers of the Little People of America (LPA)1 supportgroup.

MATERIALS AND METHODS

The Little People of America Inc. (LPA)1 is the larg-est advocacy support organization of its kind in theUnited States, consisting of individuals with skeletaldysplasias or short stature syndromes their families,and their friends. The general membership of the LPAwere asked to participate in a mailed questionnairesurvey after the purpose of the study was described indetail at the annual national meeting. Four thousandquestionnaires were mailed out to all members of LPA.Fifteen hundred individuals with short stature or, inthe case of children under age 11, their parents com-pleted the survey. There were 816 respondents withachondroplasia including 437 adults, 66 teenagers, and76 children. This analysis focuses only on the 437adults with achondroplasia.

The questionnaire consisted of a disease-specific andgeneral medical comorbidities questionnaire, a generaldemographics questionnaire (including information onself-reported diagnosis, past operations, family history,and socioeconomic indicators), and the Short Form 36(SF-36) [Ware and Sherbourne, 1992]. The question-naire on general comorbidities included hypertension,myocardial infarction, angina, congestive heart failure,diabetes mellitus, and cancer. Disease-specific prob-lems asked about included chronic allergies/sinustrouble, chronic ear infection, arthritis or rheumatism,sciatica or chronic back problems, difficulty with vi-sion, chronic lung disease, chronic skin rash, hearingdifficulty, limitations in use of upper or lower limbs dueto weakness or paralysis, chronic neck problems, spinedeformity, endocrine dysfunction, and sleeping disor-ders.

The SF-36 is a well-developed and widely used ‘‘in-strument’’ for measuring a population’s general healthstatus [Greenfield et al., 1992; Stewart et al., 1989;Tarlov et al., 1989]. It comprises eight subscales (physi-cal functioning, role physical, bodily pain, generalhealth, vitality, social functioning, role emotional, andmental health) and a health transition question. Re-cently, the Medical Outcomes Trust has developed twosummary scores based on these eight subscales calledthe Physical Component Summary (PCS) score and theMental Component Summary (MCS) score [Ware et al.,1995]. Both summary scores consist of weighted scores

from all the subscales. The PCS focuses predominantlyon the physical functioning, role physical, bodily pain,and general health subscales; in contrast, the MCS fo-cuses on mental health, role emotional, social function-ing, and vitality subscales. To facilitate data analysisand presentation, we elected to use these two summaryscores. A historical cohort based on the published nor-mative data for the U.S. population by the MedicalOutcomes Trust for the SF-36 was used as a controlgroup. The normalized scores for the general U.S.population for the PCS and MCS are both 50, with astandard deviation of 10 [Ware et al., 1994].

Data analysis was performed using PC-SAS version6.10 software package (SAS Institute Inc., Cary, NC).Univariate analyses were based on Student’s t-test orSpearman correlations as appropriate. Analysis ofvariance was used to assess age- and gender-adjusteddifferences for PCS and MCS between people withachondroplasia and the general population. A forwardstepwise selection procedure (P < 0.05) was used todevelop linear regression models to determine whichcovariates were the strongest predictors of PCS andMCS scores after adjusting for known confoundingvariables. Separate analyses were conducted for usingPCS and MCS scores as the dependent variable. A two-tailed threshold P value of 0.05 was used in all cases.

RESULTS

There were 437 adult members of the LPA with self-identified achondroplasia who participated. Self-reported height was also recorded, and those individu-als whose height was outside the range for achondro-plasia were excluded (males, 131 ± 5.6 cm or 51.5 ± 2inches; females, 124 ± 5.9 cm or 49 ± 2 inches). Themean age was 38 years (Table I). The ratio of females tomales was 1.5:1 (Table I). Most were white and hadsome level of post-high school education; 10% statedthat they had a family history of achondroplasia.Eighty-four percent had no major general medical co-morbidity. The overall mean PCS and MCS scores forthis cohort were 45.9 and 49.7, respectively. There wasno significant difference in the mean PCS and MCSscores by gender, race, level of education, or family his-tory of achondroplasia (Table I). As would be expected,there was a significant difference in PCS and MCSscores comparing those with no comorbid illness withthose with one or more comorbid illnesses.

The age- and gender-adjusted distributions of PCSscores for the general U.S. population and those withachondroplasia are shown in Figure 1. Although thePCS scores for people with achondroplasia are compa-rable to those of the general population in the secondand third decades of life, there is a statistically signifi-cant decline in scores for both males and females be-ginning in the fourth and fifth decades of life. Thisdecline appears to plateau off in the sixth decade. Thetrend toward improved scores in the seventh decademust be viewed with caution due to the small numbersof people with achondroplasia in this age category.

Figure 2 shows the age- and gender-adjusted distri-butions for MCS scores for the general population andpeople with achondroplasia. In contrast to the PCS dis-

1Little People of America Inc., National Headquarters, P.O.Box 9897, Washington, DC, 20016.

Functional Health 31

tribution, there is no significant difference in the scoresacross the age span studied. There is a trend towardhigher scores in affected individuals in the seventh de-cade of life; however, this must be interpreted cau-tiously because of the small sample size in this agecategory.

Chronic back problems were the most frequently re-ported diagnosis-related complaint in this cohort (41%,Table II). This was followed by chronic allergies/sinusproblems (38%), arthritis/rheumatism (33%), hearing

impairment (33%), spine deformity (30%), sleeping dif-ficulty (29%), chronic neck pain (20%), and paralysis orweakness of either upper or lower limbs (20%). Theremainder of the symptoms were reported by fewerthan 20% of the cohort. The mean PCS scores for thosereporting specific symptoms compared with those with-out that specific complaint were significantly lower forall symptom categories except hearing impairment andendocrine problems. Categories with PCS score differ-ences of 10 or greater included chronic back problems,arthritis, chronic neck pain, and paralysis or weaknessof either upper or lower limbs. The largest difference inscore was 16.5 for those reporting symptoms of paraly-sis or weakness. Musculoskeletal problems, particu-larly spinal deformity, pain, and associated neurologi-cal manifestations, were among the most frequent andsignificant determinants of overall physical functionand health in this cohort.

In contrast, the only symptoms that resulted in sig-nificant differences in mean MCS scores were chronicallergies/sinus problems, hearing impairment, sleepingdifficulty, chronic neck problems, chronic ear infec-tions, and chronic lung disease. Chronic ear infectionshad the greatest effect on MCS scores, with a differenceof 4.5. Overall, the differences in MCS scores were notas large as PCS scores for most symptom categories.These univariate relationships are based on multipletests and may lead to increased probability of finding asignificant relationship. However, all significant rela-tionships in Table II are for PCS scores associated withP < 0.003, suggesting a true effect after correcting formultiple tests.

There were 536 operations reported by 298 individu-als in this cohort. The three most frequent procedureswere tonsillectomy/adenoidectomy (47%), laminectomylumbar spine (23%), and osteotomy (19%; Table III). Allother surgical procedures were reported by fewer than10% of individuals. The mean PCS scores for all re-

Fig. 1. Distribution of SF-36 PCS by age in individuals with achondro-plasia and general U.S. population. The lines represent the distribution ofmean PCS scores of the SF-36 for individuals with achondroplasia and thegeneral U.S. population (from the Medical Outcomes Trust) by gender andage. Error bars represent ± one standard deviation.

TABLE I. Cohort Demographics

CharacteristicsMean PCS

(SD)aMean MCS

(SD)

Mean age (range)in years 38.1 (18–90) 45.9 (12.0) 49.7 (10.6)

GenderMale (%) 40.7 46.6 (12.1) 49.6 (9.5)Female (%) 59.3 45.5 (11.9) 49.7 (11.4)

RaceWhite (%) 96 45.8 (12.0) 49.6 (10.6)Other (%) 4 49.7 (10.7) 51.5 (12.2)

Level of educationHigh school (%) 16 43.0 (12.8) 49.7 (9.7)Some college or

vocationalschool (%) 46 46.1 (12.2) 48.8 (11.1)

Graduated fromcollege (%) 28 46.9 (11.8) 51.1 (10.2)

Postgraduatedegree (%) 10 47.9 (9.7) 49.0 (10.8)

Family historyEither parent

affected (%) 10 46.4 (11.2) 49.8 (9.8)Neither parent

affected (%) 90 45.9 (12.1) 49.7 (10.7)Comorbidities

None (%) 84 47.2 (11.6)* 50.1 (10.5)*One (%) 13 40.3 (11.9) 48.5 (11.2)Two or more (%) 3 33.7 (11.6) 43.3 (11.1)

*P < 0.05 by Student’s t-test or analysis of variance as appropriate.aSD, standard deviation.

Fig. 2. Distribution of SF-36 MCS by age in individuals with achondro-plasia and general U.S. population. The lines represent the distribution ofmean Mental Component Summary scores of the SF-36 for individualswith achondroplasia and the general U.S. population (from the MedicalOutcomes Trust) by gender and age. Error bars represent ± one standarddeviation.

32 Mahomed et al.

spondents who had reported a surgical procedure weresignificantly lower than those who reported not havingthe surgery except for the osteotomy group. There wasno significant difference in the mean MCS scores be-tween those who underwent surgery compared withthose who did not, except for the osteotomy group, inwhich the MCS scores were higher.

For the five most frequent surgical procedures in thiscohort, it is evident that disease-related symptoms stillpersist after surgery (Table IV). After tonsillectomy/adenoidectomy, more than one-third of the subjectscontinue to report problems with sleep and hearing.More than 70% of individuals after lumbar laminec-tomy complain about chronic back problems, and 50%have persistent weakness/paralysis of their limbs. Asimilar pattern is evident in those who have had eithera cervical decompression or fusion.

Multivariate linear modeling was used to determinewhich diagnosis-related symptoms were the strongestpredictors of PCS and MCS scores after adjusting forage, gender, race, education level, and general comor-bidities (Table V). The significant predictors of PCSscores were spine deformity, sleep problems, arthritis,chronic back problems, and paralysis or weakness oflimbs. Similar to the univariate analysis, the strongestpredictor was limb weakness or paralysis. In contrast,

hearing impairment, chronic allergy/sinus problems,and chronic neck pain were the only significant predic-tors of MCS scores. As would be expected, the presenceof any significant covariate was associated with a de-cline in the PCS or MCS scores.

The surgical procedures significantly associated withPCS scores in the adjusted model were limb lengthen-ing, hip surgery, foot surgery, laminectomy of cervicalspine, and laminectomy of lumbar spine. The strongesteffect was associated with those who underwent limblengthening, although the number is quite small. Theonly surgical procedure to have an impact on the MCSscores was foot surgery. This effect was relatively largeand comparable to its effect on the PCS score. Footsurgery was the only procedure to have an effect onboth the PCS and MCS scores.

DISCUSSIONThe results of this study show that there are no dif-

ferences in mean PCS and MCS scores for adults withachondroplasia with respect to gender and with respectto family history of achondroplasia. The mean PCSscores decline significantly compared with those of thegeneral population after the third decade for bothmales and females. There is no associated drop in MCSscores with increasing age in either gender group.

TABLE III. Univariate Analysis of Surgical Interventions and Outcomes*

Surgical procedure

No. of subjectswith surgery

(%)

SF-36 PCSsurgery

group (SD)a

SF-36 PCSno surgerygroup (SD) P value

SF-36 MCSsurgery

group (SD)

SF-36 MCSno surgerygroup (SD) P value

Tonsillectomy/adenoidectomy 203 (47) 44.4 (11.7) 47.6 (12.0) 0.0084 49.9 (10.4) 49.5 (11.0) 0.7353Laminectomy lumbar spine 101 (23) 37.4 (13.3) 48.7 (10.2) 0.0001 49.6 (11.8) 49.6 (10.1) 0.9829Osteotomy 84 (19) 47.1 (11.2) 45.9 (12.1) 0.3989 47.6 (11.8) 50.2 (10.3) 0.0475Cervical spine fusion 33 (8) 36.9 (12.9) 47.0 (11.4) 0.0001 52.5 (10.1) 49.6 (10.6) 0.1462Laminectomy cervical spine 32 (7) 32.7 (12.8) 47.2 (11.2) 0.0001 49.0 (9.8) 49.7 (10.7) 0.7357Correction of spinal deformity 30 (7) 39.9 (10.5) 46.8 (11.8) 0.0029 47.9 (11.8) 50.0 (10.6) 0.3090Shunting for hydrocephalus 22 (5) 45.1 (11.4) 46.4 (11.8) 0.6229 50.7 (10.6) 49.8 (10.5) 0.7062Foot surgery 14 (3) 36.6 (12.8) 46.4 (11.7) 0.0032 44.3 (15.3) 49.8 (10.5) 0.2154Hip surgery 10 (2) 31.2 (13.0) 46.5 (11.7) 0.0003 47.9 (11.8) 49.7 (10.7) 0.6416Limb lengthening 3 (1) 27.5 (1.0) 46.2 (11.9) 39.3 (4.1) 49.7 (10.7)

*Analysis based on Student’s t-test. No comparison was performed for limb lengthening due to small sample size.aSD, standard deviation.

TABLE II. Univariate Association of Disease-Related Symptoms and Outcomes*

Symptoms

No. of symptomaticsubjects (%)

n 4 437

SF-36 PCSsymptomatic

(SD)a

SF-36 PCSasymptomatic

(SD) P value

SF-36 MCSsymptomatic

(SD)

SF-36 MCSasymptomatic

(SD) P value

Chronic back problems 178 (41) 38.7 (11.7) 51.5 (8.7) 0.0001 48.9 (11.3) 50.2 (10.2) 0.2246Allergies or sinus problems 167 (38) 43.8 (11.8) 47.4 (11.8) 0.0026 47.5 (11.5) 51.1 (9.8) 0.0009Arthritis 146 (33) 38.1 (11.5) 50.3 (10.0) 0.0001 48.7 (11.4) 50.2 (10.2) 0.1849Hearing impairment 143 (33) 44.8 (12.6) 46.5 (11.6) 0.1499 47.6 (11.2) 50.7 (10.2) 0.0042Deformity of spine 132 (30) 39.7 (11.9) 49.2 (10.6) 0.0001 49.8 (11.3) 49.7 (10.3) 0.9084Sleeping difficulty 125 (29) 40.7 (13.0) 48.1 (10.9) 0.0001 47.7 (11.8) 50.5 (10.1) 0.0215Neck problems 89 (20) 37.5 (12.4) 48.2 (10.8) 0.0001 46.7 (12.1) 50.4 (10.1) 0.0087Paralysis or weakness

of arm/leg 86 (20) 32.9 (11.5) 49.4 (9.5) 0.0001 48.0 (12.0) 50.0 (10.2) 0.1532Chronic ear infection 73 (17) 41.7 (13.3) 47.0 (11.4) 0.0006 45.9 (10.9) 50.4 (10.4) 0.0008Dermatitis 46 (11) 39.2 (13.2) 46.8 (11.5) 0.0001 46.8 (10.9) 50.0 (10.6) 0.0517Difficulty with vision 38 (9) 39.8 (13.9) 46.7 (11.5) 0.0007 47.4 (12.2) 49.9 (10.5) 0.1790Chronic lung disease 29 (7) 36.9 (13.9) 46.7 (11.5) 0.0001 45.8 (10.6) 49.9 (10.6) 0.0424Endocrine problems 7 (2) 41.6 (11.6) 46.0 (12.0) 45.0 (10.4) 49.8 (10.7)

*Analaysis based on Student’s t-test. No tests were performed for endocrine problems due to small sample size.aSD, standard deviation.

Functional Health 33

The decline in PCS scores in the middle decades oflife was associated with an increase in the frequency ofmusculoskeletal complaints, particularly the symp-toms of spinal stenosis and chronic lumbar pain. A po-tential problem of survivor bias occurs in the over-65-year category, because the number of individuals in thegroup is small.

The MCS scores did not deviate from the generalpopulation across the age spectrum. According to mul-tivariate analysis, chronic allergies and sinus problemswere the most prevalent diagnosis-related disease toaffect the MCS scores. Hearing problems were alsofound to be significant.

Nearly two-thirds of this cohort underwent one ormore operations. Even after surgical treatment, a sig-nificant number of individuals reported the presence ofdisease-related symptoms. Individuals who reportedhaving undergone surgical procedures generally havelower PCS scores. There were, however, minimal ef-fects to the MCS scores. None of the procedures foundto be significantly correlated with either PCS or MCSscores were positively correlated.

Because this study is of cross-sectional design anddoes not compare patients before and after treatment,there are a number of possible interpretations of thesurgical data: (1) these operations do not provide ad-equate restoration of physical function; (2) these pro-cedures are performed too late in the natural history ofthe disorder to fully ameliorate the physical and men-tal health limitations; (3) the patients who underwentsurgery were antecedently the sickest and most dis-abled, therefore biasing the postsurgical scores; (4) thepatients would have been even worse off if they had not

had surgery; and (5) at least in the case of spinal ste-nosis, these patients had inadequate decompressionsby current standards.

The cohort was derived from the membership of theLPA and may, therefore, represent selection bias. LPAis dedicated to helping people with short stature andconsists of individuals who are very motivated and pro-mote a positive attitude toward individuals with shortstature. These individuals might be better adjusted totheir diagnosis compared with individuals who are notmembers of the group, and thus MCS scores of LPAmembers did not deviate from the general population[Brust et al., 1976; Scott, 1977]. On the other hand,LPA may select far healthier and more functional in-dividuals, suggesting that the disease-related symp-toms may be worse in the general achondroplasia popu-lation.

Every effort was made to ensure an accurate self-reported diagnosis of achondroplasia. A self-reportedheight excluded those who were not in the range ofaverage achondroplasia stature. Although most indi-viduals who are members of LPA have seen a numberof medical practitioners who should have confirmed thecorrect diagnosis, experience suggests that achondro-plasia is often a favored adopted diagnosis by somewith other dwarfing conditions.

The literature on self-reporting health status ques-tionnaires indicates that patients are accurate, do notexaggerate symptoms, and correlate well with physi-cian’s assessments of wellbeing [McHorney et al., 1993,1994; Ware and Sherbourne, 1992]. To the best of ourknowledge, this is the first report on the functionalhealth status of adults with achondroplasia. The data

TABLE IV. Frequency of Disease-Related Symptoms in Subjects With and Without Surgery

Surgical procedure

No. with surgery(% of total sample)

n 4 437No. symptomatic,

no surgery group (%)No. symptomatic,surgery group (%) Symptoms

Tonsillectomy/adenoidectomy 203 (47) 58 (25) 75 (37) Sleep problems (i.e., apnea)40 (17) 37 (18) Chronic ear infections68 (29) 83 (41) Hearing difficulties

Laminectomy lumbar spine 101 (23) 118 (35) 72 (71) Sciatica or chronic back problems44 (13) 50 (50) Weakness/paralysis of extremities

Osteotomy 84 (19) 127 (36) 26 (31) ArthritisCervical spine fusion 33 (8) 85 (21) 16 (48) Neck problemsLaminectomy cervical spine 32 (7) 73 (18) 27 (84) Neck problems

69 (17) 25 (77) Weakness/paralysis of extremities

TABLE V. Adjusted Analysis for Disease-Specific Symptoms and Surgical Interventions With Outcomes*

Disease symptomsRegressioncoefficient 95% CLa Surgical interventions

Regressioncoefficient 95% CL

PCS covariatesSpine deformity −2.49 (−4.47, −0.51) Limb lengthening −14.34 (−25.38, −3.31)Sleep problems −3.58 (−5.50, −1.66) Hip surgery −10.52 (−17.32, −3.72)Arthritis −4.12 (−6.22, −2.02) Foot surgery −7.80 (−13.43, −2.17)Chronic back problem −6.49 (−8.45, −4.53) Laminectomy C-spine −8.81 (−12.65, −4.97)Extremity weakness −9.55 (−11.88, −7.22) Laminectomy L-spine −8.67 (−11.04, −6.30)

MCS covariatesHearing impairment −2.67 (−4.88, −0.45) Foot surgery −8.57 (−14.67, −2.47)Chronic allergy/sinuses −3.76 (−5.92, −1.60)Neck problems −3.85 (−6.44, −1.26)

*Analysis based upon multiple linear regression with adjustment for age, gender, race, education level, and comorbidities; critical P value < 0.05.aCL, confidence limits.

34 Mahomed et al.

from this study indicate that the functional health sta-tus of people with achondroplasia is not drastically re-duced. This information will be useful to obstetricians,primary care physicians, and pediatricians for counsel-ing pregnant couples and parents of children withachondroplasia in terms of the functional health statusof their children in adulthood. The data point out thatmore research is needed to establish the effectivenessof surgical operations and suggest that more emphasisis needed on developing prophylactic interventions thatcould prevent and/or minimize the functional limita-tions associated with achondroplasia. The data may ar-gue in favor of parent support groups such as LPA.

ACKNOWLEDGMENTS

The authors thank Charles I. Scott, Jr., M.D., Chair-man, and the members of the LPA Medical AdvisoryBoard for their cooperation.

This work was supported in part from the generalresearch funds, Pratt Orthopaedics, New EnglandMedical Center (Boston, MA), and the Allen GreenbergSkeletal Dysplasia Foundation, John Hopkins Hospital(Baltimore, MD). Dr. Mahomed is a recipient of Cana-dian Arthritis Society Research Fellowship 95035 andthe Health Services Research Fellowship from theAcademy of Orthopaedic Surgeons of America and theOrthopaedic Research and Education Foundation.

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