Radiology Notes

My notes during radiology residency, fellowship, and beyond…

Archive for November 2010

Skeletal Dysplasia

leave a comment »

Differential diagnoses of skeletal dysplasias
based on clinical, radiographic and ultrasound findings.


Skull Thorax Limbs Spine Pelvis
Achondrogenesis Type IA (Houston-Harris) poorly ossified short, round chest with multiple rib fractures very short, broad tibiae & fibulae, wedge-like femora with proximal metaphyseal


unossified vertebral bodies hypoplastic arch-like iliac bones

with short vertical ischia

Achondrogenesis Type IB (Fraccaro), poorly ossified short chest with thin ribs, cupped ends, no fractures very short

with trapeziod femora, crenated tibiae, unossified fibulae


vertebral bodies

hypoplastic crenated iliae
Achondrogenesis Type II


large calvarium with posterior ossification defect barrel-shaped, with short ribs very short with mild-moderate metaphyseal

changes, long fibulae

thoracolumbar ossification short iliae,

flat acetabular roots, unossified pubic bones, ossified ischia

Kniest dysplasia frontal flattening, maxillary hypoplasia,

shallow orbits

short ribs club-like metaphyses, delayed ossification

of femoral heads

diffuse flattening, coronal clefts small ilia,

increased acetabular angles with irregular edges

Thanatophoric dwarfism frontal bossing+ clover-leaf


narrow, pear-shaped, short, bowed, with metaphyseal flaring


normal ossification small sacrosciatic notches, spiculated acetabulum
Osteogenesis Imperfecta, Type II soft and membranous flail

chest at birth

short fracture liability normal
Achondroplasia megalocephaly slight rib flaring rhizomelic,

with leg bowing, trident hands

thoracolumbar kyphosis, lordosis


short iliac wings
Hypochondroplasia normal normal short vertebral canal


Spondyloepiphyseal dysplasia normal short barrel chest, +

pectus carinatum

mild rhizomelic shortening with bowing severe kyphoscoliosis


retarded ossification of pubic bones
Asphyxiating thoracic dysplasia Normal narrow, long, short

anteriorly cupped ribs

+ post-axial polydactyly,

variably short

normal square, short iliae, flat acetabulae
Hypophosphatasia thin and membranous markedly reduced ossification, short short with bowing, long bones are frayed poor ossification

with hypoplastic vertebrae


Written by lmwong

November 14, 2010 at 8:35 pm