7. Reading an x ray
It is not getting the “appearance”
It is not commenting “oh! I have seen it
before”
And not distracted by the “obvious”- it may
not be the causative pathology
We should have a systematic approach
www.similima.com 7
8. ABC’s of bone Radiology
Look for
Alignment
Bones
Abnormal lucency
Abnormal sclerosis
Periosteal reaction
Abnormal contour
Cartilage
Soft Tissue
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9. Alignment
Subluxation
A displacement of a bone in relation to the apposing
bone at the joint, resulting in a partial loss of
continuity of the joint surfaces.
Dislocation
A displacement of a bone in relation to the apposing
bone at the joint, resulting in a complete loss of
continuity of the joint surfaces.
Diastasis
A displacement of a bone in relation to the apposing
bone in a slightly movable (e.g. sacroiliac) or
synarthrodial joint (cranial sutures).
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12. Decreased Opacity (Lucency)
Lucency comes in several flavors. Depending on the exact
morphology and distribution of the lucency, our
differential diagnosis may vary widely.
Lucent line
fracture
Focal lucency
tumor
infection
Diffuse lucency
drugs
endocrine / metabolic
tumor
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13. Lucent line
A linear lucency is the classic
sign of a fracture. If a fracture
is displaced enough, it is easy
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14. Focal lucency
With focal lucencies, bone tumors and osteomyelitis are two of the
top entities on the differential diagnosis.
In the rest of the world, a handful of benign tumors are seen
occasionally, and the only malignant tumors commonly seen
are metastases and multiple myeloma.
In practice, the patient’s history is often key in
distinguishing tumor and infection, as they sometimes
appear quite similar on radiographs.
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17. focal lucencies
focal lucencies, bone tumors
and osteomyelitis are two of
the top entities on the
differential diagnosis.
only malignant tumors
commonly seen are
metastases and multiple
myeloma
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19. Look for
Age of the patient
Size of the lesion
Margins of the lesion
Matrix- the “inside” of the lesion
Location in the bone
Periosteal reaction - present or not?
multiplicity
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25. a long lesion in a long bone,
think of
fibrous dysplasia.
www.similima.com 25
26. Simple cyst,
enchondroma,
and fibrous dysplasia
can mimic each other and can be
hard to distinguish.
www.similima.com 26
27. Giant cell tumors
nearly always
occur near a joint surface.
www.similima.com 27
28. Lucent lesions of the sternum
should be considered
malignant
until proven otherwise
(Helms CA, 1983).
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29. Certain bones in the body are
"epiphyseal equivalents".
lucent lesions in these areas,
the classic epiphyseal entities such as chondroblastoma,
giant cell tumors and aneurysmal bone cysts.
They are
patella,
calcaneus,
most apophyses.
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30. Diffuse lucency
Diffuse lucency usually
bespeaks some global
process capable of
affecting the entire
skeleton.
A metabolic bone
disorder such as
osteoporosis
multiple myeloma
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35. Bone impaction or rotation
Although the classic
sign of a fracture is a
lucent line, some
fractures present
otherwise.
In cancellous
bones
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36. Fracture callus
Some fractures are so
subtle that you may
miss them altogether
at first, and only
diagnose them once
they have started to
heal due to the
formation of fracture
callus.
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37. Reactive sclerosis due to tumor
diffusely sclerotic
metastsis are seen in a
very slow process
(prostatic carcinoma)
or a patient with diffusely
lytic mets who has been
successfully treated (with
resultant healing and
sclerosis of these
metastatic deposits).
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41. Periosteal reaction
Depends on whether the lesion is
slow growing or rapidly growing
Slow growing- periosteum is able to
produce bone at the same rate as tumor
grows- so solid periosteal reaction
Rapidly growing lesion -the perisoteum
cannot cope up- hence interrupted pattern
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42. Periosteum produces bone when stimulated
Type of periosteal reaction depends on the
process than the periosteum
Slow growing- solid periosteal reaction
Faster growing layered or lamellar type
Rapid, steady growth -sun burst,
codeman’s triangle
Mixed patterns
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43. Solid Lamellar sunburst Codeman’s
triangle
Types of periosteal
reaction
Mixed type
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50. Cartilage
we can’t really see
cartilage on plain
radiographs, but we can
still use these films to
infer a few rough ideas
decreased joint space about how the cartilage is
doing. Hyaline articular
cartilage is what
increased joint space separates the bones in a
synovial joint. This space
taken up by the cartilage
chondrocalcinosis is termed the "joint
space" on a plain
radiograph.
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51. Marked joint space
narrowing is noted in the
superior weight-bearing
portion of the joint space
in this patient with
osteoarthritis.
Subchondral sclerosis
and marked
osteophytosis are also
noted.
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52. Chondrocalcinosis
(arrows) is noted in
the hyaline articular
cartilage and menisci
of this patient with
calcium
pyrophosphate
deposition (CPPD)
disease
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53. Soft Tissue
When looking at the soft tissues, one can
occasionally see a variety of useful
findings on plain films, such as:
swelling
gas
calcification
mass
www.similima.com 53
56. small to large amorphous Ca++ in the
Dystrophic damaged tissue -- may progress to
ossification (formation of cortex and medullary
space are then seen)
CPPD chondrocalcinosis; occasionally
associated with calcifications in the
soft tissues of the spine
Metastatic calcification finely speckled Ca++ throughout soft
tissues
Tumoral calcinosis big globs of Ca++, usually near a
joint
Metastatic osteosarcoma amorphous, fluffy, confluent
collection of Ca++
Primary soft tissue amorphous, fluffy, confluent
collection of Ca++
osteosarcoma www.similima.com 56