achondroplasia, multipleepiphyseal dysplasia

1. DWARFISM
Presentation by- Nikhil .S.U
Chair person - Dr Ravishankar
Co-chair person- Dr Prakash
JSS hospital, Mysore

2. Introduction
 Bone dysplasias ( Dwarfism)
 Greek word – Dys- disordered
Plasia – development
 Shortening of the growing bones in
different proportions due to multiple gene
defects
 >200 disorders, abnormal growth of
bones and cartilage
 Height less than 147cms, <3rd percentile

3. Classification
 Proportion
 Proportionate- symmetric decrease in
both trunk and limb length. eg-constitutional,
familial, endocrinopathies,
mucopolysaccharidoses.
 Disproportionate dwarfism:-
1. Short-trunk variety (e.g., Kniest
syndrome–spondyloepiphyseal)
2. Short-limb variety (e.g.,
achondroplasia, diastrophic dysplasia)

4.  Based on location in short limb variety
rhizomelic = root, e.g., bones of the arm
or thigh
mesomelic = middle, e.g., bones of the
forearm or leg
acromelic = end, e.g., bones of hands
and feet.
micromelic = entire limbs are shortened

5.  Source
chondro = of cartilage
osteo = of bone
spondylo = of the vertebrae

6.  Lethal
Achondrogenesis
Thanatophoric dysplsia
Asphyxiating thoracic dysplasia(ATD)
Dysplasia epiphysealis punctata
Osteogenesis imperfecta
 Non leathal
Majority of dysplasia

7. Achondroplasia
 Syn; chondrodystrophia fetalis
 Most common form of disproportionate
dwarfism
 AD
 Incidence - 1.5 per 10,000 live births.
 GENETICS
 Spontaneous mutation in Fibroblast Growth
Factor Receptor 3(FGFR 3)
 There is failure in the cartilaginous
proliferative zone of physis- quantitative
defect
 Associated with advanced paternal age

8.  Signs and symptoms
Normal trunk and short limbs with
hypotonia

9.  Lumbar stenosis & excessive lordosis
with spinal cord / nerve root
compression
 Radial head subluxation
 Normal intelligence but delayed motor
milestones

10. Radiographic findings
 Spine: narrowed interpedicular
distance(L1 to S1)
 pedicular shortening
 T12/L1wedging,
generalized posterior
vertebral scalloping

11.  Bullet shaped vertebral bodies
 Thick short pedicles
 Lumbosacral hyperlordosis

14. Treatment
 Lumbar stenosis: decompression
(laminectomy & discectomy) and fusion
of the spine for a developing neurologic
deficit (usually in children older than age
10)
 Posterior fusion of cervical spine is
recommended in individual cases
 Foramen magnum stenosis:
decompression
 Progressive kyphosis: if fail bracing,
anterior and posterior fusion are
indicated for residual kyphosis greater
than 50 degrees by age 5 years.

15.  Genu varum: Tibial osteotomies or
hemiepiphysiodesis
 Limb lengthening - adolescence
usually is the time when lengthening is
undertaken through callodiastasis
(lengthening through a metaphyseal
corticotomy) have been well
described, with a high rate of
complications.
 Growth hormone is being used to
augment the height

16. SPONDYLOEPIPHYSEAL
DYSPLASIA
 Defect in gene encoding Type 2
collagen
 Abnormal epiphyseal development in
the upper and lower extremities-disproportionate
dwarfism
 Retinal detachment and respiratory
problems are common.

17.  Eyes are wide-set, the neck is short,
and the chest appears barrel shaped.
 Genu valgum, is common.
 Lumbar lordosis may be accentuated
and is usually due to hip flexion
contractures. The lordosis gives the
abdomen a protuberant appearance.
 A waddling gait is produced by the
coxa vara

18.  Generalised severe platyspondyly
 Increased intervertebral disc height
 Open staircase vertebrae
 Kyphosis/ scoliosis
 Widening sclerosis irregularity of
tubular bones
 Irregular femoral epiphysis
 Retarded bone maturation

19. Treatment
 In case of cervical instability- posterior
cervical fusion from the occiput or C1
to C2 with halo vest immobilization is
necessary
 When the scoliosis exceeds 50
degrees or is associated with
significant kyphosis, fusion with
standard instrumentation is effective

20.  Valgus osteotomy when the neck–
shaft angle is less than 100 degrees,
when the Hilgenreiner–epiphyseal
angle is greater than 60 degrees

21. CHONDRODYSPLASIA
PUNCTATA
 Multiple punctate calcifications seen on
radiographs during infancy.
 2 types
1. Conradi-Hünermann syndrome- XR-normal
life expectancy(arylsulfatase E (ARSE)
gene mutation)
2. Autosomal recessive- fatal during the first
year of life, rhizomelic form.
 Short stature, dry and scaly skin, occasional
heart defects, and cataracts and spinal
deformities are common.
 Congenital vertebral anomalies - scoliosis or
kyphosis

22.  Strippling / punctate calcification
tarus, carpus, long bone epiphysis,
vertebral transverse process, ischium
& pubis
 Soft tissue calcification around the
joints present

23. Treatment
 Orthopaedic treatment consists primarily
of managing the scoliosis- early anterior
and posterior spinal fusion
 Prognosis ; bad prognosis, most patients
die due to respiratory complications by 1
year of age

24. KNIEST SYNDROME
 Defect in COL2A1 gene
 AD- short-trunked, disproportionate
dwarfism with joint
stiffness/contractures, scoliosis,
kyphosis, and hypoplastic pelvis and
spine
 Otitis media and hearing loss are
frequent.

25.  Radiology ; Osteopenia and dumbbell-shaped
bones

26.  Treatment ;
Early therapy for joint contractures,
Reconstructive procedures for early
hip degenerative arthritis
Correction of the spinal deformity

27. METAPHYSEAL
CHONDRODYSPLASIA
 Heterogeneous group of disorders
characterized by metaphyseal
changes of tubular bones with normal
epiphyses
 Defect in the proliferative and
hypertrophic zones of the physis

28. Types

29. Schmid type
 More common, less severe
 Genetic defect is in type X collagen-
AD
 Short-limbed dwarfism not diagnosed
until patient is older
 Metaphyseal flaring & irregularity with
widening of physis.
 Enlarged capital femoral epiphysis

31. treatment
 Valgus osteotomy of the proximal
femur may be indicated for children
with significant coxa vara

32.  Recurrence of deformity with growth is
common.
 Hemiepiphysiodesis or stapling may
improve angular deformities in some
children.

33. Jansen type
 Rare and most severe- AD
 Genetic defect in parathyroid
hormone–related peptide
 Retardation, markedly short-limbed
dwarfism with wide eyes, monkey-like
stance, and hypercalcemia
 x ray shows triking bulbous
metaphyseal expansion of long bones

34. McKusick type
 AR-
 Cartilage-hair dysplasia (hypoplasia of
cartilage and small diameter of hair)
 Most common in the Amish population and in
Finland
 Atlantoaxial instability is common
 Ankle deformity develops as a result of fibular
overgrowth distally.
 Abnormal immunocompetence, increased
risk for malignancies, intestinal
malabsorption, and megacolon

36. treatment
 Orthopaedic treatment is usually
directed toward the ankle and foot-calcaneal
sliding osteotomy as
treatment for hindfoot varus
 Growth hormone has recently been
used

37. MULTIPLE EPIPHYSEAL
DYSPLASIA
 COMP gene mutation(Cartilage
oligomeric matrix protein )
 Prevalence of MED was 9 per 100,000
 Short-limbed, disproportionate
dwarfism often not manifested until
between the ages of 5 and 14.
 A mild form (Ribbing) and a more
severe form (Fairbanks) exist
 Waddling gait, and early hip arthritis
are common

38.  Irregular, delayed ossification at
multiple epiphyses
 Short, stunted metacarpals and
metatarsals, irregular proximal femora,
abnormal ossification (flattened tibial &
femoral condyles, patella
with double layer),
valgus knees

39. Multiple epiphyseal dysplasia.
Abnormal femoral heads
Flattened tibial &
femoral condyles

40.  Treatment :
 Caution regarding weight gain
 Treat limb alignment and perform
early joint replacement
 Shelf acetabular augmentation in
some patients - to improve coverage
of the misshapen femoral head
 Osteotomies may be helpful in
realigning the lower extremities when
angular deformities exist, particularly
at the knee

41.  stapling may provide correction in
some cases

42. DD s for MULTIPLE
EPIPHYSEAL DYSPLASIA
 Perthes disease - usually affects
unilateral hip but when bilaterals each
hip is in a different stage of the
disease.- this is not the case in MED
 Spondyloepiphyseal dysplasia-abnormal
epiphyseal development
with typical spine involvement which is
not found in MED

43. MUCOPOLYSACCHARIDOSIS
 Due to hydrolase(lysosomal storage
disorder) enzyme deficiency-mucopolysaccharides
accumulate in
the body & produce proportionate
dwarfism.
 Normal mucopolysaccharide excretion
in urine <15mg/24 hrs
 It wil be >100mg/24hrs

44. All are AR, autosomal recessive; except MPS 2-XR, X-linked
recessive.

45. Hurlers syndrome

46.  The facies coarse and heavy.
 The head is enlarged, and hydrocephalus-meningeal
deposits.
 The skull is abnormally shaped, and the forehead is low.
 Premature closure of the sagittal and metopic sutures of the
skull leads to a prominent longitudinal ridge that may cross
the forehead.
 The ears are low and the eyes are wide-set.
 The teeth are poorly formed and widespread.
 The nostrils are wide, and the nose has a depressed bridge
and broad tip.
 The lips are everted, the tongue is enlarged, and the mouth
is open. “Chronic rhinitis” with noisy mouth-breathing is
always present and is due to narrowing of the nasopharynx
by enlarged adenoids and mucosal deposits.
 This, combined with the presence of hernias, may be the
presenting sign of the disease
 Clouding of the cornea is a universal feature of the disease

47.  Urinary excretion of dermatan/heparan
sulfate
 Treatment
 Bone marrow transplantation has
increased the life span for patients
with this disorder- Transplantation
before the age of 24 months yields
better clinical results

48.  Surgical reconstruction, including
reduction, femoral osteotomy, and
pelvic osteotomy- for Hip dysplasia
 Carpal tunnel syndrome- Treated by
surgical decompression

49. Hunter syndrome
Bone marrow transplantation has been used in isolated cases of Hunter's syndrome

50. Morquio syndrome

53. Bullet-shaped metacarpals

54. Wide, unossified femoral heads
Wine-glass shaped inner pelvic contour

55. treatment
 Manifesting myelopathy necessitates
decompression and cervical fusion
 Genu valgum may be treated by
realignment osteotomy
 Carry substantial anesthetic risk
because of their cervical instability and
respiratory and cardiac abnormalities

57. Thanatophoric dysplasia
 Disproportionately small ribcage,
extremely short limbs and folds of
extra skin on the arms and legs
 lethal skeletal dysplasia
 Narrow chest, small ribs and under
developed lungs

60.  Children with this condition are usually
stillborn or die shortly after birth from
respiratory failure
 Survivors have difficulty breathing on
their own and require respiratory
support

61. DIASTROPHIC DYSPLASIA
 AR.
 Deficiency in sulfate transport protein
 Features
 Severe, short-limbed dwarfism
 Cleft palate (59% of cases)
 Severe joint contractures (especially hip and
knee)
 Cauliflower ears (80% of cases), hitchhiker’s
thumb
 Rigid clubfeet

62. Hitchhiker’s thumb
Cleft palate

63.  Radiologic findings
 Spine radiographs reveal cervical
kyphosis (often severe, necessitating
immediate treatment), thoracolumbar
kyphoscoliosis
 (83% of cases), spina bifida occulta,
and atlantoaxial instability.

64.  Treatment
 Quadriplegia is a major concern with
deformities of the cervical spine.
 Surgical release of clubfoot deformities
 Osteotomies for contractures
 Spinal fusion often required- Anterior fusion
with fibular strut grafting and posterior
fusion with halo immobilization

65. CLEIDOCRANIAL DYSPLASIA
(DYSOSTOSIS)
 AD
 Proportionate dwarfism that affects
bones formed by intramembranous
ossification (clavicles, cranium, pelvis)
 Defect in -Core-binding factor alpha 1
(Cbfa1)- transcription factor for
osteocalcin

68.  Delayed closure of skull sutures,
frontal bossing
 Treatment
Excision of the clavicular fragments
can decompress the brachial plexus
Intertrochanteric valgus osteotomy if
neck-shaft angle is less than 100
degrees

69. Summary

74.  At the end of the survey &
investigation prognosis has to be
conveyed to the family members
which includes genetic counselling
and appropriate occupation
Dysplastic may be of short
stature but not a lesser
human being.

75. References
 Tachdjian's Pediatric Orthopaedics
 Review of Orthopaedics- Miller
 Radiology of syndromes, metabolic
disorders & skeletal dysplasia- Taybi &
Lachman’s
 Essentials of skeletal radiology- Yochum
& Rowe’s
 Turek s orthopaedics
 Campbell's Operative Orthopaedics
 Wikipedia

76. Thank you