This presentation aims at teaching the residents on how to Approach a case of skeletal dysplasia

1. DR NAVNI GARG
MBBS, DNB (RADIOLOGY)

2. CLASSIFICATION OF SKELETAL
ABNORMALITIES
 Osteochondrodysplasias (skeletal dysplasia)
 Dysostoses
 Idiopathic osteolysis
 Primary disturbances of growth
 Constitutional diseases of bone with known
pathogenesis (chromosomal, metabolic etc.)

3. OSTEOCHONDRODYSPLASIA DYSOSTOSES
- Abnormalities of bone
and/or cartilage growth
- Because of abnormal
gene expression
- Phenotypes continue to
evolve throughout
lifespan
- Altered blastogenesis in
first 6 weeks of IU life
- Phenotype fixed
- Donot evolve to involve
normal bones

4. Skeletal dysplasia
 Heterogeneous group of disorders
characterised by abnormal shape, size,
growth, number and density of bones
 Affects the growth and development.
 Disproportionate long bones, spine, and
skull

5. Osteochondrodysplasias
Classification
I. Defects of growth of tubular bone and/or
spine
A. Identifiable at birth
B. Identifiable later in life
II. Disorganized development of cartilage and
fibrous components of skeleton
III. Abnormalities of density of cortical
diaphyseal structure and/or metaphyseal
modeling

6. I. Defects of growth of tubularI. Defects of growth of tubular
bone and/or spinebone and/or spine
A. Identifiable at birth
 Thanatophoric dysplasia
 Chondrodysplasia punctata
 Achondroplasia
 Chondroectodermal dysplasia
 Spondyloepiphyseal dysplasia congenita
 Cleidocranial dysplasia
 Achondrogenesis
 Metatrophic dwarfism
 Diastrophic dwarfism
 Asphyxiating thoracic dysplasia (jeune syndrome )
A. Identifiable later in life
 Hypochondroplasia
 Metaphyseal chondrodysplasia
 Multiple epiphyseal dysplasia
 Pseudoachondroplasia

7. II. Disorganized development of
cartilage and fibrous components
of skeleton
 Multiple cartilaginous exostoses
 Enchondromatosis (olliers
disease)
 Fibrous dysplasia
 Dysplasia epiphysealis
hemimelica

8. III. Abnormalities of density of
cortical diaphyseal structure
and/or metaphyseal modeling
 Osteogenesis Imperfecta
 Osteopetrosis
 Pycnodysostosis
 Osteopoikilosis
 Melorheostosis
 Diaphyseal dysplasia
 Metaphyseal dysplasia
 Osteopathia striata

9. ASSESSMENT OF SKELETAL
DYSPLASIA
 PRENATAL (ULTRASOUND)
 POST NATAL
DISPROPORTION
GENERAL EXAMINATION
RADIOLOGY

10. PRENATAL ASSESSMENT

11. SKULL
 Head circumference and BPD : to exclude
macrocephaly
 Shape, mineralization, and degree of
ossification
 Interorbital distance measured to exclude
hyper- or hypotelorism
 Other features such as micrognathia, short
upper lip, abnormally shaped ears, frontal
bossing, and cloverleaf skull should be
assessed

12. CHEST
1.Look for markers of Pulmonary hypoplasia
 Chest circumference less than the 5th
percentile for gestational age
 Chest–trunk length ratio less than 0.32
 Femur length–abdominal circumference ratio
less than 0.16

13. Hypoplastic thorax occurs in – lethal dysplasia
e.g.
 Thanatophoric dysplasia
 Achondrogenesis
 Osteogenesis imperfecta
 Camptomelic dysplasia
 Chondroectodermal dysplasia
 Asphyxiating thorasic dysplasia

14. 2. Absent clavicle : CCD
3. Absent scapula : Camptomelic dysplasia

15. SPINE
 Relative total length
 Curvature : to exclude scoliosis
 Mineralization of vertebral bodies and neural
arches
 Look for platyspondyly (flattened vertebral
body shape with reduced distance between
the endplates) : Thanatophoric dysplasia

16. SPINE : Platyspondyly

17. LONG BONES
- Long bones lengths
- Absence and malformation
- Hypoplasia : Rhizomelia, Mesomelia, Rhizo-
mesomelia, Acromelia
- Curvature, degree of mineralization and
fractures

18. - Femur length–foot length ratio (normal = >1,
<1 suggests skeletal dysplasia ) (14-40 wks)

19. HANDS AND FEET
 Pre- or postaxial polydactyly (presence of
more than 5 fingers)
 Syndactyly :soft tissue or bony fusion
 Clinodactyly : Deviation of finger
 Any other deformities : hitchhiker’s thumb,
rocker-bottom feet, and clubbed feet or
hands

20. POLYDACTYLY

21. DIASTROPHIC DYSPLASIA

22. PRENATAL ASSESSMENT CONCLUSION

23. DISPROPORTIONAL LIMBS
1. Does the abnormality affect the proximal (rhizomelic),
middle (mesomelic), or distal (acromelic) segment?
2. Is polydactyly, clinodactyly, or syndactyly present?
3. Are there any fractures, curved bones, or
joint deformities, or clubbing of the foot or hand?
4. Are metaphyseal changes present?
5. Is there a premature appearance of ossification centers?
6. Are there any hypoplastic or absent bones?

24. SPINE INVOLVEMENT
1. Is the spine short because of missing parts
(eg, sacral agenesis)?
2. Is there abnormal curvature? (Scoliosis)
3. Is there shortening of vertebral bodies?
4. Are all parts of the spine equally affected?
(achondrogenesis)
5. Is platyspondyly present (thanatophoric
dysplasia)?

25. THORAX INVOLVED
1. Is the thorax extremely small (thanatophoric dysplasia)?
2. Is the thorax long and narrow (Jeune syndrome)?
3. Are the ribs extremely short (short-rib
polydactyly)?
4. Are fractures present (osteogenesis imperfecta type II)?
5. Is there clavicular aplasia, hypoplasia, or partitioning
(cleidocranial dysostosis)?
6. Is the scapula normal or abnormal (camptomelic
dysplasia) ?

26. POSTNATAL ASSESSMENT

27. POSTNATAL
ASSESSMENT I :
DISPROPORTION Upper/lower segment ratio:
• 1.7 newborn
• 1.0 ages 2-8yrs
• 0.95 adult
Short trunk dwarfism : metatrophic dysplasia,
SED
Short limb dysplasia : achondroplasia,
metaphyseal chondrodysplasia

28.  Sitting height : ascertains trunkal shortening

29. Limb lengths:
• Rhizomelia
(humerus and femur)
• Mesomelia
(radius, ulna, tibia and
fibula)
• Acromelia (Hands
and feet)

30. Spine: assess for
 scoliosis
 kyphosis
 lordosis

31. POSTNATAL ASSESSMENT II
GENERAL EXAMINATION
 General examination: facial features, hair
quality, dental health, nails
 Systemic features: renal problems, cardiac
abnormalities
 Developmental history: Most normal
 Family history
 Ethnicity: SEMD with joint laxity in SA

32. CLINICAL SETTING
 Mental retardation - Chondrodysplasia punctata
 Dental deformities - CCD
 Disproportionately large head - Achondroplasia
,thanotophoric dysplasia
 Congenital cataract - Chondrodysplasia punctata
 Myopia - SED congenita
 Renal involvement – Asphyxiating thoracic dysplasia

33. POSTNATAL ASSESSMENT III
Radiology : skeletal survey
 Skull (AP and lateral) to include atlas and axis
 Spine (AP and lateral)
 Chest (AP)
 Pelvis (AP)
 One Upper limb (AP)
 One Lower limb (AP)
 Hand (bone age)AP
 Feet (AP)
Additional views
 Lat knee for patella
 Lat foot for calcaneum
In cases with epiphyseal stippling/limb asymmetry- B/L limbs

34.  In preterm fetuses and stillbirths, babygram
i.e. anteroposterior (AP) and lateral films
from head to foot
 Imaging of other family members suspected
of having same condition

35. WHAT TO LOOK FOR
 A – Anatomical localisation : axial /
appendicular/ combinations
 B – Bones
 C – Complications

36. A - Anatomical localization
Axial skeletonAxial skeleton
SkullSkull
MandibleMandible
ClavicleClavicle
RibsRibs
SpineSpine
PelvisPelvis
Cranio/cranial - Achondroplasia, CCDCranio/cranial - Achondroplasia, CCD
Mandibulo - PyknodysostosisMandibulo - Pyknodysostosis
Cleido - CCDCleido - CCD
Costo - ATD, ThanatophoricCosto - ATD, Thanatophoric
Spondylo/vertebral - SEDCSpondylo/vertebral - SEDC
Achondroplasia, MPSAchondroplasia, MPS
Ischio/ilio/pubic - Achondroplasia, MPSIschio/ilio/pubic - Achondroplasia, MPS

37. Anatomical localization
Appendicular skeletonAppendicular skeleton
LocationLocation Epiphyseal -Epiphyseal - Chondrodysplasia punctataChondrodysplasia punctata, SED,, SED,
Hemimelica, Multiple epiphyseal dysplasiaHemimelica, Multiple epiphyseal dysplasia
Metaphyseal –Metaphyseal – Achondroplasia, Achondrogenesis,Achondroplasia, Achondrogenesis,
ATD, Chondroectodermal dysplasiaATD, Chondroectodermal dysplasia
Diaphyseal -Diaphyseal - Engleman’s diseaseEngleman’s disease
ShorteningShortening Rhizomelic -Rhizomelic - Achondroplasia, hypochondroplasia,Achondroplasia, hypochondroplasia,
pseudochondroplasia, SEDC,pseudochondroplasia, SEDC,
metaphyseal dysplasia, thanatophoricmetaphyseal dysplasia, thanatophoric
Chondrodysplasia punctata,Chondrodysplasia punctata,
Mesomelic -Mesomelic - Mesomelic dysplasiasMesomelic dysplasias
Acromelic -Acromelic - Acrodysostosis, ATDAcrodysostosis, ATD

38.  Epiphyseal dysplasia –
hypoplastic, irregular
epiphyses
 Metaphyseal dysplasia
–widened, flared or
irregular metaphyses
 Diaphyseal dysplasia –
cortical thickening or
marrow space
expansion or reduction

39.  Epiphyseal dysplasia
 Metaphyseal dysplasia

40. Stippled epiphysis in
Chondrodysplasia punctata

41.  Irregular or stippled epiphysis differential
diagnosis
• Congenital hypothyroidism
• Morquio’s syndrome
• Multiple epiphyseal dysplasia
• Trisomy 18 , 21
• Prenatal infections
• Warfarin embryopathy

42. Cone shaped epiphysis in
trichorhinophalangeal syndrome

43. Flaring of metaphyses in
metaphyseal dysplasia
(pyles disease)

44.  ERLENMEYER FLASK DEFORMITY
DIFFERENTIAL DIAGNOSIS
• Thalassaemia
• Gaucher’disease
• Niemann pick’s disease
• Lead poisoning
• Osteopetrosis

45. DIAPHYSEAL DYSPLASIA

46. Combinations:
 • Spondylo-epiphyseal dysplasia (SED)
 • Spondylo-metaphyseal dysplasia (SMD)
 • Metaphyseal-epiphyseal dysplasia (MED)
 • Spondylo-epiphyseal-metaphyseal
dysplasia(SEMD)

48. B - BONES

49. StructureStructure
 General appearance
 Tumorous lesions such as exostoses
 Metaphyseal striations : osteopathia striata
 Bone islands e.g. osteopoikilosis

50. Multiple exostoses

51. METAPHYSEAL
STRIATIONS
BONY ISLANDS

52. ShapeShape
 Clover leaf skull : thanatophoric dysplasia
 Spatulated ribs : hurler
 Vertebral bodies
1. wafer thin, platyspondyly (Thanatophoric dysplasia)
2. hooked(MPS)
3. bullet shaped ( achondroplasia)
4. spool shaped : pycnodysostosis
5. coronal clefts : chondrodysplasia punctata
6. heaped up vertebrae : SED tarda
7. Posterior scalloping of vertebral bodies
 Acetabular roof
sloping (MPS)
horizontal roof (Achondroplasia)
 Telephone handle femora : thanatophoric dysplasia

53. THANATOPHORIC DYSPLASIA
Clover leaf shaped skull seen due to fusion
of the cranial sutures which cause lateral
temporal bulge

54. Hurler : spatulated/ paddle
appearance of ribs

55. Hurler syndrome :
Anteroinferior beaking

56. Morquio : central beaking
of vertebrae

57. Spool shaped vertebrae :
Pycnodysostosis

58. Achondroplasia : bullet
shaped vertebrae with
posterior scalloping

59. Coronal clefting in
Chondrodysplasia punctata

60. Hyperostotic bone in the posterior
2/3rd of the end plates -hump shaped
or heaping up vertebra in SED tarda

61. Posterior scalloping
• ACHONDROPLASIA
• MORQUIO SYNDROME
• HURLER SYNDROME
• NEUROFIBROMATOSIS
• INTRASPINALTUMOUR
• MARFAN’S SYNDROME
• EHLER DANLOS SYNDROME
• ANKYLOSING SPONDYLITIS
• ACROMEGALY

62. Achondrodysplasia :
Horizontal acetabular roofs

63. Pycnodysostosis : oblique
roofed acetabulum

64. Thanatophoric dysplasia :
telephone receiver femora

65. SizeSize
Absolute or relative
Small skull – craniosynostosis
Large skull – achondroplasia, MPS
Longer fibula – hypochondroplasia
Short fibula – CCD
Short ribs – asphyxiating thorasic
dysplasia

66. Asphyxiating thorasic dysplasia : small
thorax with short ribs , horizontally
oriented

67. Density
 Increased : Osteopetrosis , pyknodysostosis
 Decreased : Hypophosphatasia , OI

68. Osteopetrosis

69. Osteopetrosis : sandwich appearance of
vertebrae due to sclerosis (more at
end plates)

70. Pyknodysostosis : sclerosis
of calvaria and base of
skull

72. Melorheostosis : focal
sclerosis

73. Sum : too many , too fewSum : too many , too few
 Supernumerary teeth - chondroectodermal dysplasia
 Supernumerary / bifid ribs : CCD
 Multiple patellar centres - multiple epiphyseal dysplasia
 Multiple calcaneal centres - Larsen’s Syndrome
 Fused carpals - chondroectodermal dysplasia


74. Soft
tissues
 Wasting
 Excessive soft tissues
 Contractures and calcification
(melorheostosis, hypophosphatasia)

75. Complications
 Achondroplasia – atlantoaxial instability
spinal canal stenosis
compression myelopathy
 Epiphyseal dysplasia – genu varum
 Fractures in osteogenesis imperfecta
 Morquios, SEDC – atlantoaxial instability
 Pseudoachondroplasia, OI, SED tarda – Early OA
 MPS – Kyphoscoliosis
 Limb length discrepancies as in Epiphyseal stippling,
dysplasia epiphysealis
 Malignancy e.g in Multiple cartilaginous exostoses

76. When to do CT and MRI
 For concurrent brain anomalies
 Atlantoaxial instability
Compressive myelopathy
 CT 3D reconstruction – Osteotomies
Cosmetic surgeries

77. Making a diagnosis
An accurate diagnosis requires a multidisciplinary
approach, i.e., combined clinical, pediatric,
genetic, biochemical, radiological and
pathological.
Rule out acquired causes of bone problems:
• Neuromuscular disorders
• Chronic diseases – JIA
• Poorly healed fractures
• Metabolic bone problem

78. Classification of bone dysplasias ( radiologically)Classification of bone dysplasias ( radiologically)
 Epiphyseal dysplasias
 Chondrodysplasia punctata- dominant and
recessive type
 Multiple epiphyseal dysplasia
 Dysplasia epiphysealis hemimelica
 Spondyloepiphyseal dysplasia- congenital
and tarda
 Metaphyseal dysplasia
 Thanatophoric dwarfism
 Asphyxiating thoracic dysplasia
 Chondroectodermal dysplasia
 Achondroplasia
 Hypochondroplasia
 Hypophosphatasia
 Sclerosing dysplasias
 Osteopetrosis
 Osteopoikilosis
 Osteopathia striata
 Melorheostosis
 Pyknodysostosis
 Progressive diaphyseal dysplasia
 Infantile cortical hyperostosis
 Osteopenic dysplasias
 Mucopolysaccharidoses and
mucolipidoses
 Osteogenesis imperfecta
 Ehlers danlos syndrome
 Major involvement of spine
 Spondyloepiphyseal dysplasia
 Diastrophic dwarfism
 Spondylometaphyseal dysplasia
 Pseudoachondroplasia
 Single segment involvement
 Mesomelic dwarfism
 Cleidocranial dysplasia
 Larsen syndrome
 Others
 Diaphyseal aclasis
 Enchondromatosis
 Fibrous dysplasia