Learning Radiology xray montage
 
 
 
 
 

21 Imaging Findings Simulating Fractures


Accessory Ossicle
Apophysis
Normal Epiphyseal Plate
Multiple ossification centers are
common in epiphyses and are
smooth and well-corticated
Apophysis of the 5th MT runs in a
longitudinal direction; fractures are
usually transverse
Don't confuse the undulations
of the humeral epiphyseal plate
for a fracture
Bipartite Patella
Nutrient Channel (Canal)
Normal Excrescence
Bipartite patella almost always
affects the upper outer pole of
patella; 57% are bilateral
Nutrient channels or canals run
diagonally only in the cortices of
certain bones
Radial spur is normal variant
occurring on the lateral aspect of the radius at the site of the physis
Normal Apophysis
Limbus Vertebra
Normal Excresence
The apophysis of the tibial tubercle
(tuberosity) fuses at age 14-18 years
Most commonly affects antero-
superior border of single vertebra
in lumbar spine
This is a normal bony
excresence from the scaphoid that
can be mistaken for a fracture
Sesamoids
Skin Laceration
Apophysis
Sesamoids are ossicles embedded in a tendon that aid in movement; they are common in the feet and hands
Air beneath lacerations may superimpose
on the bone simulating fractures; look at multiple projections
The greater and lesser trochanters
are apophyses which fuse at 15-20
years of age
Lack of Fusion
Mach Line
Accessory Epiphyses
Hyoid Bone fuse later in life
usually by age 40; it is therefore
common to see and unfused hyoid
"Mach Lines" are optical illusions which produce a black line where none exists; they are common at the base of the dens
In a child, when in doubt, think of obtaining the opposite side for comparison; mouse-over

 

Synchondroses

 

Costovertebral Junction
Accessory Ossicle
3 main temporary joints in pelvis: ilio-pubic, ischio-pubic and ilio-ischial; bilateral and usually symmetric
Every rib attaches to the spine at the
costo-vertebral junction; not to be
confused with a fracture

Os Acetabuli Marginalis Superior
Normal variant
May be bilateral

 

Multiple Ossification Centers

 

Sesamoids
Accessory Ossicle

The calcaneal apophysis frequently has multiple centers of ossification and appears denser than rest of calcaneous

There are almost always sesamoids of the thumb; they are well-corticated and smooth-edged, unlike fractures
Os Trigonum-accessory ossicle just posterior to the talus normally found in 5-15% of people