The International Working Group on Bone Dysplasiasmet in Los Angeles, California on August 5 and 6, 1997,to perform the third official revision of the 1972 Paris No-menclature of Constitutional Disorders of Bone. In thelast revision (1992), the classification was reoriented onradiodiagnostic and morphologic criteria and groupedmorphologically similar disorders into ªfamiliesº of dis-orders based on presumed pathogenetic similarities.

In the present, newly revised nomenclature, the fa-milies of disorders were to some extent rearrangedbased on recent etiopathogenetic information concern-ing the gene and/or protein defect in these disorders. Inthose disorders in which the basic defect was well docu-mented, they were regrouped into distinct families, inwhich the component disorders were due to mutationsin the same gene. These included the ªachondroplasiagroupº of disorders with mutations in fibroblast growthfactor receptor 3; the ªdiastrophic dysplasiaº group ofdisorders, with mutations in the diastrophic dysplasiasulfate transporter gene; the ªtype II collagenopathies,ºwith mutations in type II collagen; and the ªtype XI col-lagenopathiesº with mutations in cartilage-oligomericmatrix protein (COMP). Several new groups of disor-

ders were added, including the ªlethal skeletal dyspla-siaº group with fragmented bones and theªmiscellaneous neonatal severe dysplasiaº group. Otherfamilies were renamed, such as the ªosteodysplasticslender bone groupº. Because of the large number ofdysplasias with increased bone density, this group wassubdivided into three new families: ªincreased bonedensity without modification of bone shapeª; ªincreasedbone density with diaphyseal involvementª, and ªin-creased bone density with metaphyseal involvementº.

References for most of the skeletal dysplasias can beobtained through a text such as the third chapter of theTaybi/Lachman book The Radiology of Syndromes,Metabolic Disorders and Skeletal Dysplasias, 4 th Edi-tion, or through on-line access of the Mendelian Inheri-tance in Man (OMIM) on the Internet directly or byaccessing the International Skeletal Dysplasia Web Site(http://www.csmc.edu/genetics/skeledys) where eachdisorder is hyperlinked to OMIM. Other references fornon-referenced disorders are listed below.

Ralph S. Lachman International nomenclatureand classification of theosteochondrodysplasias (1997)International Working Groupon Constitutional Diseases of BoneDavid L. Rimoin, MD, Ph. D. (Los Angeles) (Chair); Clair A. Francomano,MD (Bethesda); Andres Giedion, MD (Zurich); Christine Hall, MD (Lon-don); Ilkka Kaitila, MD (Helsinki); Dan Cohn, Ph. D. (Los Angeles); Ro-bert Gorlin, DDS (Minneapolis); Judith Hall, MD (Vancouver); WilliamHorton, MD (Portland); Deborah Krakow, MD (Los Angeles); MartineLe Merrer, MD (Paris); Ralph Lachman, MD (Los Angeles); Stefan Mund-los, MD (Mainz); Andrew K. Posnanski, MD (Chicago); David Sillence,MD (Sydney); Jürgen Spranger, MD (Mainz); Matthew Warman, MD (Cle-veland); Andrea Superti-Furga, MD (Zurich); and William Wilcox, MD(Los Angeles)

R. S.Lachman ())International Skeletal Dysplasia Registry,Room 1001, 444 S.San Vicente Blvd.,Los Angeles, CA 90048, USA

The workshop was supported by grantsfrom the National Institutes of Health (HD35637-01); The March of Dimes; SeronoCorporation; Pharmacia-Upjohn, andOceana Investment Co.

We wish to thank Drs. Pierre Maroteauxand Peter Beighton for their helpful com-ments.

Pediatr Radiol (1998) 28: 737±744Ó Springer-Verlag 1998

738

References

SED with brachydactylyReginato AJ, Passano GM, Neumann G,Falasca GF, Diaz-Valadez M, JimenezSA, Williams CJ (1994) Familial spondy-loepiphyseal dysplasia tarda brachydac-tyly and precocious osteoarthritis. ArthRheum 37: 1078

Mild SED with premature onset arthrosisAnderson IJ, Tsipouras P, Scher C, Ra-mesar RS, Martel W, Beighton P (1990)Spondyloepiphyseal dysplasia, mild au-tosomal dominant type is not due to pri-mary defects of type II collagen. Am JMed Genet 37: 272

Other late-onset spondyloepi(meta)phy-seal dysplasias ± Namaqualand typeBeighton P, Christy G, Learmonth D III(1984) Namaqualand hip dysplasia: anautosomal dominant entity. Am J MedGenet 19: 161

Mesomelic dysplasia, Kozlowski-ReardontypeKozlowski K, Bacha B, Brachimi L,Massen (1993) Mesomelic dysplasia ofthe upper extremities with other ab-normalities. Pediatr Radiol 23: 108

Reardon W, Hall CM, Slaney S, Huson SM,Connell J, Al-Hilaly N, Fixsen J, Barait-ser M, Winter RM (1993) Mesomeliclimb shortness. Am J Med Genet 47: 788

Osteogenesis imperfecta with unusual ske-letal lesions (with radiolucent lesions ofthe mandible)Levin LS, Wright JM, Byrd DL, Green-way G, Dorst JP, Irani RN, Pyeritz RE,Young RJ, Laspia CL (1985) Am J MedGenet 21: 257

Axial osteosclerosisWhyte MP, Fallon MD, Murphy WA,Teitelbaum SL (1981) Axial osteomala-cia. Clinical, laboratory and genetic in-vestigation of an affected mother andson. Am J Med 71: 1041

Astley-Kendall dysplasiaAstley R, Kendall AC (1980) A bonedysplasia for diagnosis. Ann Radiol 2:121

Shinohara carpal-tarsal osteolysisShinohara O, Kubot C, Kimira C,Nishimura G, Takahashi S (1991)Essential osteolysis associated withnephropathy, corneal opacity and pul-monary stenosis. Am J Med Genetic41: 482

739

International nomenclature of constitutional disorders of bone

Osteochondrodysplasias Mode ofinheritance

Presentat birth

Chromosomallocus

Gene Protein

1. Achondroplasia groupThanatophoric dysplasia, Type I AD + 4p16.3 FGFR3 FGFR3Thanatophoric dysplasia, Type II AD + 4p16.3 FGFR3 FGFR3Achondroplasia AD + 4p16.3 FGFR3 FGFR3Hypochondroplasia AD � 4p16.3 FGFR3 FGFR3Other FGFR3 disorders

2. Spondylodysplastic and other perinatally lethal groupsLethal platyspondylic skeletal dysplasias

(San Diego type, Torrance type, Luton type) SP +Achondrogenesis type 1A AR +

3. Metatropic dysplasia groupFibrochondrogenesis AR +Schneckenbecken dysplasia AR +Metatropic dysplasia (various forms) AD +

4. Short-rib dysplasia (SRP) (with or without polydactyly) groupSRP type I, Saldino-Noonan AR +SRP type II, Majewski AR +SRP type III, Verma-Naumoff AR +SRP type IV, Beemer-Langer AR +Asphyxiating thoracic dysplasia (Jeune) AR +Chondroectodermal dysplasia

(Ellis-van Creveld dysplasia) AR + 4p16

5. Atelosteogenesis ± omodysplasia groupAtelosteogenesis type I

(includes ªBoomerang dysplasiaº) SP +Omodysplasia I (Maroteaux) AD +Omodysplasia II (Borochowitz) AR +Otopalatodigital syndrome type II XLR +Atelosteogenesis type III SP +de la Chapelle dysplasia AR +

6. Diastrophic dysplasia groupDiastrophic dysplasia AR + 5q32-q33 DTDST Sulfate transporterAchondrogenesis 1B AR + 5q32-q33 DTDST Sulfate transporterAtelosteogenesis type II AR + 5q32-q33 DTDST Sulfate transporter

7. Dyssegmental dysplasia groupDyssegmental dysplasia

Silverman-Handmaker typeAR +

Dyssegmental dysplasiaRolland-Desbuquois type

AR +

8. Type II collagenopathiesAchondrogenesis II (Langer-Saldino) AD + 12q13.1-q13.3 COL 2A1 Type II collagenHypochondrogenesis AD + 12q13.1-q13.3 COL 2A1 Type II collagenKniest dysplasia AD + 12q13.1-q13.3 COL 2A1 Type II collagenSpondyloepiphyseal dysplasia (SED) congenita AD + 12q13.1-q13.3 COL 2A1 Type II collagenSpondyloepimetaphyseal dysplasia SEMD

Strudwick type AD + 12q13.1-q13.3 COL 2A1 Type II collagenSED with brachydactyly AD 12q13.1-q13.3 COL 2A1 Type II collagenMild SED with premature onset arthrorisis AD � 12q13.1-q13.3 COL 2A1 Type II collagenStickler dysplasia (heterogeneous, some not

linked to COL2A1) AD + 12q13.1-q13.3 COL 2A1 Type II collagen

9. Type XI collagenopathiesStickler dysplasia (heterogeneous) AD + 6p21 COL 11A1 Type XI collagenOtospondylomegaepiphyseal dysplasia AR + 6p21.3 COL 11A2 Type XI collagen

(OSMED) AD + 6p21.3 COL 11A2 Type XI collagen

10. Other spondyloepi-(meta)-physeal [SE(M)D] dysplasiasX-linked spondyloepiphyseal dysplasia tarda XLD � Xp22.2-p22.1Other late-onset spondyloepi-(meta)-physeal

dysplasias (Irapa) (Namaqualand, et al.) AR �Progressive pseudorheumatoid dysplasia AR �

740

International nomenclature of constitutional disorders of bone (continued)

Osteochondrodysplasias Mode ofinheritance

Presentat birth

Chromosomallocus

Gene Protein

Dyggve-Melchior-Clausen dysplasia AR +Wolcott-Rallison dysplasia AR �Immuno-osseous dysplasia-Schimke AR +Opsismodysplasia AR +Chondrodystrophic myotonia (Schwartz Jampel)

type 1, type 2AR + 1q36-34

Spondyloepiphyseal dysplasia with joint laxity AR +Sponastrime dysplasia AR �SEMD short limb ± abnormal calcification AR +

11. Multiple epiphyseal dysplasias & pseudoachondroplasiaPseudoachondroplasia AD � 19p12-13.1 COMP COMPMultiple epiphyseal dysplasia (MED) AD �

(Fairbanks and Ribbing types) AD � 19p12-13.1 COMP COMPOther MEDs ? � 1p32.2-33 COL 9A2 Type IX collagen

12. Chondrodysplasia punctata (stippled epiphyses group)Rhizomelic type AR + 4p16-p14 PEX 7 Peroxin-7Zellweger syndrome AR + 7q11.23 PEX 1

AR + 6p21.1 PEX 6 Peroxin-6AR + 7q11.23 PEX 1 Peroxin-1AR + 12 PEX 5 Peroxin-5AR + 8q21.1 PEX 2 Peroxin-2

Conradi-Hünermann type XLD + Xq28 CPXDX-linked recessive type XLR + Xp22.3 CPXRBrachytelephalangic type XLR + Xp22.32 ARSE Arylsulfatase ETibial-metacarpal type AD +Vitamin K-dependent coagulation defect AR +

13. Metaphyseal dysplasiasJansen type AD + 3p22-p21.1 PTHR PTHR/PTHRPSchmid type AD � 6q21-q22.3 COL 10A1 COL10 achainMcKusick type (cartilage-hair hypoplasia) AR + 9p13Metaphyseal anadysplasia XLR? �Metaphyseal dysplasia with pancreatic

insufficiency and cyclic neutropenia(Shwachman Diamond) AR �

Adenosine deaminase deficiency AD � 20q-13.11 ADA Adenosinedeaminase

Metaphyseal chondrodysplasia± Spahr type

AR �

Acroscyphodysplasia (various types) AR �

14. Spondylometaphyseal dysplasias (SMD)Spondylometaphyseal dysplasia Kozlowski type AD +Spondylometaphyseal dysplasia (Sutcliffe type) AD +SMD with severe genu valgum (includes Schmidt

and Algerian types) AD +SMD Sedaghatian type AR +

15. Brachyolmia spondylodysplasiasHobaek (includes Toledo type) AR �Maroteaux type AR �Autosomal dominant type AD �

16. Mesomelic dysplasiasDychondrosteosis (Leri-Weill) AD �Langer type (homozygous dyschondrosteosis) AR +Nievergelt type AD +Kozlowski-Reardon type AR +Reinhardt-Pfeiffer type AD +Werner type AD +Robinow type, dominant AD �Robinow type, recessive AR �Mesomelic dysplasia with synostoses AD +

741

International nomenclature of constitutional disorders of bone (continued)

Osteochondrodysplasias Mode ofinheritance

Presentat birth

Chromosomallocus

Gene Protein

17. Acromelic and acromesomelic dysplasiasAcromicric dysplasia AD +Geleophysic dysplasia AR +Weill-Marchesani dysplasia AR +Cranioectodermal dysplasia AR +Trichorhinophalangeal dysplasia, type I AD + 8q24.12 TRPS1Trichorhinophalangeal dysplasia, type II

(Langer-Giedion) AD + 8q24.11-q24.13 TRPS1 +EXT 1

Trichorhinophalangeal dysplasia, type III AD +Grebe dysplasia AR + 20q11.2 CDMP1 Cartilage-derived

morphogenic pro-tein 1

Hunter-Thompson dysplasia AR + 20q11.2 CDMP1 Cartilage-derivedmorphogenic pro-tein 1

Brachydactyly type A1±A4 AD +Brachydactyly type B AD +Brachydactyly type C AD + 21q11 CDMP1 Cartilage-derived

morphogenic pro-tein 1

AD 12q24Brachydactyly type D AD +Brachydactyly type E AD �Pseudohypoparathyroidism

(Albright Hereditary Osteodystrophy)Various types ± see OMIM

� 20q13 GNAS1 Quanine nucleooxi-de binding proteinof edenylate cyclasea-subunit

Acrodysostosis SP (AD) �Saldino-Mainzer dysplasia AR �Brachydactyly-hypertension dysplasia (Bilginturan) AD + 12pCraniofacial conodysplasia AD +Angel-shaped phalango-epiphyseal dysplasia

(ASPED) AD +Acromesomelic dysplasia AR +

18. Dysplasias with prominant membranous bone involvementCleidocranial dysplasia AD + 6p21 CBFA1 Core binding factor

a1-subunitOsteodysplasty, Melnick-Needles XLD �Precocious osteodysplasty (terHaar dysplasia) AR +Yunis-Varon dysplasia AR +

19. Bent-bone dysplasia groupCampomelic dysplasia AD + 17q24.3-q25.1 SOX 9 SRY-box 9Kyphomelic dysplasia ?AR +Stüve-Wiedemann dysplasia AR +

20. Multiple dislocations with dysplasiasLarsen syndrome AD + 3p21.1-p141 LARILarsen-like syndromes

(including La Reunion Island) AR +Desbuquois dysplasia AR +Pseudodiastrophic dysplasia AR +

21. Dysostosis multiplex groupMucopolysaccharidosis IH AR � 4p16.3 IDA a-1-IduronidaseMucopolysaccharidosis IS AR � 4p16.3 IDA a-1-IduronidaseMucopolysaccharidosis II XLR � Xq27.3-q28 IDS Iduronate-2-sulfa-

taseMucopolysaccharidosis IIIA AR � 17q25.3 HSS Heparan sulfate

sulfatase

742

International nomenclature of constitutional disorders of bone (continued)

Osteochondrodysplasias Mode ofinheritance

Presentat birth

Chromosomallocus

Gene Protein

Mucopolysaccharidosis IIIB AR � 17q21 N-Ac-a-D-glucosa-minidase

Mucopolysaccharidosis IIIC AR � Ac-CoA:a-glucosa-minidase-N-acetyl-transferase

Mucopolysaccharidosis IIID AR � 12q14 GNS N-Ac-glucosamine-6-sulfatase

Mucopolysaccharidosis IVA AR � 16q24.3 GALNS Galactose-6-sulfa-tase

Mucopolysaccharidosis IVB AR � 3p21-p114.2 GLBI b -GalactosidaseMucopolysaccharidosis VI AR � 5q13.3 ARSB Arylsulfatase BMucopolysaccharidosis VII AR � 7q21.11 GUSB b -GlucuronidaseFucosidosis AR � 1p34 FUCA a-Fucosidasea-Mannosidosis AR � 19p13.2-q12 MAN a-Mannosidaseb -Mannosidosis AR � 4 MANB b -MannosidaseAspartylglucosaminuria AR � 4q23-q27 AgA Aspartylgluco-

saminidaseGM 1 Gangliosidosis, several forms AR + 3p21-p14.2 GLB 1 b -GalactosidaseSialidosis, several forms AR +/� 6p21.3 NEU a-NeuraminidaseSialic acid storage disease AR +/� 6q14-q15 SIASDGalactosialidosis, several forms AR 20q13.1 PPGB b -Galactosidase

protective proteinMultiple sulfatase deficiency AR +/� Multiple sulfatasesMucolipidosis II AR + 4q21-23 GNPTA N-Ac-Glucosamine-

phosphotransferaseMucolipidosis III AR � 4q21-23 GNPTA N-Ac-Glucosamine-

phosphotransferase

22. Osteodysplastic slender bone groupType I osteodysplastic dysplasia AR +Type II osteodysplastic dysplasia AR +Microcephalic osteodysplastic dysplasia AR

23. Dysplasias with decreased bone densityOsteogenesis imperfecta I

(without opalescent teeth) AD +/� 17q21 COL 1A1 a(1)I procollagenOsteogenesis imperfecta I

(with opalescent teeth) AD +/� 17q21 COL 1A1 a(1)I procollagenAD +/� 7q22.1 COL 1A2 a(2)I procollagen

Osteogenesis imperfecta II AD + 17q21 COL 1A1 a(1)I procollagenAD + 7q22.1 COL 1A2 a(2)I procollagenAR + 17q21 COL 1A1 a(1)I procollagen

Osteogenesis imperfecta III AD + 17q21 COL 1A1 a(1)I procollagenAD + 7q22.1 COL 1A2 a(2)I procollagenAR + 7q22.1 COL 1A2 a(2)I procollagenAR +

Osteogenesis imperfecta IV(without opalescent teeth) AD + 7q22.1 COL 1A2 a(2)I procollagen

AD + 17q21 COL 1A1 a(1)I procollagenOsteogenesis imperfecta IV

(with opalescent teeth) AD + 7q22.1 COL 1A2 a(2)I procollagenAD + 17q21 COL 1A1 a(1)I procollagen

Cole-Carpenter dysplasia SP +Bruck dysplasia AR +Singleton-Merton dysplasia AR �Osteopenia with radiolucent lesions of

the mandible ADOsteoporosis-pseudoglioma dysplasia AR � 11q12-q13Geroderma osteodysplasticum AR �Hyper IGE syndrome with osteopenia AR �Idiopathic juvenile osteoporosis SP �

743

International nomenclature of constitutional disorders of bone (continued)

Osteochondrodysplasias Mode ofinheritance

Presentat birth

Chromosomallocus

Gene Protein

24. Dysplasias with defective mineralizationHypophosphatasia ± perinatal lethal and infantile

forms AR + 1p36.1-p34 ALPL Alkaline phospha-tase

Hypophosphatasia ± adult form AD � 1p36.1-p34Hypophosphatemic rickets XLD � Xp22.2-p22.1 PHEX X-linked hypophos-

phatemia proteinNeonatal hyperparathyroidism AR + 3q21-q24,

19p13.3CASR Calcium sensor

Transient neonatal hyperparathyroidism withhypocalciuric hypercalcemia AD + 3q21-q24 CASR Calcium sensor

AD + 19p13.3

25. Increased bone density without modification of bone shapeOsteopetrosis

Precocious type AR + 11q12-13Delayed type AD � 1p21Intermediate type AR +With renal tubular acidosis AR + 8q22 CA2 Carbonic anhy-

drase IIAxial osteosclerosis

Osteomesopyknosis AD �With bamboo hair AR �

Pyknodysostosis AR + 1q21 CTSK Cathepsin KOsteosclerosis Stanescu type AD +Osteopathia striata

Isolated SP �With cranial sclerosis AD �

Sponastrime dysplasia AR +Melorheostosis SP �Osteopoikilosis AD �Mixed sclerosing bone dysplasia SP �

26. Increased bone density with diaphyseal involvementDiaphyseal dysplasia Camurati Engelmann AD �Craniodiaphyseal dysplasia ?AR +Lenz Majewski dysplasia SP +Endosteal hyperostosis

van Buchem type AR �Worth type AD �Sclerosteosis AR �With cerebellar hypoplasia AR +

Kenny Caffey dysplasia AD, AR �Osteoectasia with hyperphosphatasia

(Juvenile Pagets) AR �Diaphyseal dysplasia with anemia AR �Diaphyseal medullary stenosis with bone

malignancy (Hardcastle) AD �

27. Increased bone density with metaphyseal involvementPyle dysplasia AR �Craniometaphyseal dysplasia

Severe type AR +Mild type AD � 5p15.2-p14.2Other types

Frontometaphyseal dysplasia XLR �Dysosteosclerosis AR �

XLROculodentoosseous dysplasia AD +

AR +Trichodentoosseous dysplasia AD � 17q21

744

International nomenclature of constitutional disorders of bone (continued)

Osteochondrodysplasias Mode ofinheritance

Presentat birth

Chromosomallocus

Gene Protein

28. Neonatal severe osteosclerotic dysplasiasBlomstrand dysplasia AR +Raine dysplasia ? +Prenatal onset Caffey disease ?AR +

29. Lethal chondrodysplasias with fragmented bonesGreenberg dysplasia AR +Dappled diaphyseal dysplasia AR +Astley-Kendall dysplasia AR +

30. Disorganized development of cartilaginous and fibrous components of the skeletonDysplasia epiphysealis hemimelica SP �Multiple cartilaginous exostoses AD � 8q23-q24.1 EXT 1 Exostosin-1

AD � 11p12-p11 EXT 2 Exostosin-2AD � 19p EXT 3

Enchondromatosis, Ollier SP �Enchondromatosis with hemangiomata, (Maffucci) SP �Spondyloenchondromatosis AR �Spondyloenchondromatosis with basal ganglia

calcification AR �Dysspondyloenchondromatosis �Metachondromatosis ADOsteoglophonic dysplasia AD +Genochondromatosis AD �Carpotarsal osteochondromatosis AD �Fibrous dysplasia (McCune-Albright and others) SP mosaic � 20q13 GNAS1 Guanine nucleotide

protein, a subunitJaffe Campanucci SPFibrodysplasia ossificans progressiva AD + 14q22-q23 BMP 4 Bone morphogenic

protein 4Cherubism AD �Cherubism with gingival fibromatosis AR �

31. OsteolysesMulticentric predominantly carpal and tarsal

in the handMulticentric carpal-tarsal osteolysis withand without nephropathy AD �Shinohara carpal-tarsal osteolysis �

Multicentric predominantly carpal, tarsal andinterphalangealFrancois syndrome AR �Winchester syndrome AR �Torg syndrome AR �Whyte Hemingway carpal-tarsal phalangealosteolyses AD �

Predominantly distal phalangesHadju-Cheney syndrome AD �Giacci familial neurogenic acroosteolysis AR �Mandibulo acral syndrome AR �

Predominantly involving diaphyses and metaphysesFamilial expansile osteolysis AD � 18q21.1-q22Juvenile hyaline fibromatosis AR +

32. Patella dysplasiasNail patella dysplasia AD � 9q34.1 NPS 1Scypho-patellar dysplasia AD +