Transcript Image Evaluation Chapter 3 - Faculty Web Sites If you are a s

Image Evaluation
Chapter 3
Critique of Upper Extremity
Hand (PA)
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ID requirements
Marker
No preventable artifacts
Contrast & density
? True PA
?long axes of 3rddigit and metacarpal
aligned
Hand (PA)
• ? Soft tissue overlap
• ? IP, MP, & CM joints open and
phalanges & metacarpals not
foreshortened and thumb is in 45
degree oblique position
• ? 3rd MP joint in center
Hand (medial oblique)
• Not enough rotation: midshafts of
metacarpals are evenly spaced and
metacarpal heads are not
superimposed
• Too much rotation: 3rd -5th
metacarpal midshafts are
superimposed
Hand ( medial oblique)
• ? Long axes of 3rd digit and
metacarpal aligned
• ? Soft tissue overlap
• ? IP, MP joints open and phalanges
not foreshortened, thumb may be
lateral or oblique
• ? 3rd MP join in center
Hand ( lateromedial)
• 2nd – 5th superimposed ( palpate
knuckles)
• If not the 2nd metacarpal is
demonstrated anterior to the 3rd –
5th metacarpal and the hand is
rotated internally or pronated
Hand ( lateromedial)
• ? Long axes of metacarpals aligned
• ? IP joints open and phalanges not
foreshortened
• MP joints in center
• Optional Positioning: extension &
flexion
Wrist ( PA)
• ? True PA : styloids of radial & ulnar
are lateral and medial edges of each
bone; radioulnar articulation is open
with minimal superimposition of
metacarpal bases
• Rotation is affected by hand,
humerus, & elbow movements
Wrist ( PA)
• If externally rotated, carpal and
metacarpal are superimposed on
medial side of wrist
• If internally rotated, carpal and
metacarpal laterally superimposes
and shows more pisiform and hamate
Wrist ( PA)
• If hand & wrist are rotated, the
radioulnar articulation is closed
• If humerus & elbow are rotated, ulna
placement changes
• The ulna & radius cross each other if
humerus is not abducted
Wrist (PA)
• ?carpal bones at center of field
• Film should include carpal bones, ¼ of
distal ulna and radius, and ½ of the
proximal metacarpals.
Wrist ( medial oblique)
• ?45 degree medial oblique
• ?trapezoid & trapezium without
superimposition, with trapeziotrapezoidal
joint space open
• ?2nd CM and scaphotrapezium joint spaces
demonstrated
• ?long axes of 3rd metacarpal and radius
aligned
Wrist (Lateral)
• ? True lateral – distal end of
scaphoid & pisiform & radius with
ulna superimposed
• ?90 degrees
• If rotated the distal scaphoid &
pisiform relationship changes and the
pronator fat stripe is obscured
Wrist (lateral)
• If rotated externally (hand
supinated) distal scaphoid is seen
posterior to the pisiform
• If rotated internally (hand pronated)
distal scaphoid is seen anterior to
the pisiform
Wrist (Ulnar-flexed)
• ?ulnar flexed
• ?scaphoid seen without
foreshortening and long axes of 1st
metacarpal and radius aligned
• If patient can’t flex enough angle 20
degrees
Wrist(ulnar-flexed)
• ?scaphoid in center of field
• See carpal bones, radioulnar
articulation & proximal 1st – 4th
metacarpals on film
• Scaphoid is most common fractured
carpal bone
Forearm (AP)
• ?long axis of forearm aligned
• Forearm midshaft in center of field
• wrist radius & ulna, elbow joints & forearm
soft tissue seen on film
• ?distal forearm in true AP- radial styloid is
seen in profile laterally & very little
superimposition of the metacarpal bases
of ulna & radius
Forearm (AP)
• ?proximal forearm in true AP
• ?radial head & tuberosity
superimpose lateral part of proximal
ulna. If on film, the medial and
lateral humeral epicondyles are seen
in profile
Forearm ( lateral)
• Anode heel effect- density is less at
anode end of tube than cathode
• So, we need to position which part of
forearm at the anode end?
• Soft tissue sightings – anterior &
posterior fat pads and the supinator
fat stripe at the elbow; pronator fat
stripe at the wrist
Forearm ( lateral)
• ?long axis of forearm aligned
• ?midshaft of forearm at center of
field
• ? Wrist, radius & ulna & elbow joints
and forearm soft tissue on film
Forearm ( lateral)
• Proximal forearm & distal humerus
positioning:
• Elbow flexed 90 degrees – poor elbow
positioning obscures fat pads that we need
to see for diagnosis
• The radial tuberosity is superimposed by
the radius and is not seen in profile
• Distal humerus in true lateral position
Elbow ( AP)
• ? True AP projection
• Medial & lateral humeral epicondyles are
seen in profile
• Detecting elbow rotation(1)epicondyles no
seen in profile(2)radial head & tuberosity
are seen with more than slight
superimposition of the ulna(3)coronoid is
seen in profile
Elbow (AP)
• ?radial tuberosity medially in profile
& eliminates crossing of the radius &
ulna
• Capitulum-radius joint is open
• When patient can’t extend elbow; ap
proximal forearm& ap distal humerus
Elbow (medial & lateral
oblique)
• ?capitulum-radial joint open
• ?elbow joint at center of field
• ?elbow joint, ¼ proximal forearm, distal humerus
on film
• Medial oblique: 45 degrees medially
• Coronoid process, trochlear notch & medial aspect
of trochlea in profile
• Trochlear-coronoid joint is open with
superimposition of radial head & neck over ulna
Elbow(medial & lateral
oblique)
• Lateral oblique: 45 degrees laterally
• ?captitulum & radial tuberosity are
seen in profile
• ?radial head, neck, and tuberosity
seen without superimposing ulna &
radioulnar joint is seen
Elbow (lateral)
• Posterior fat pad is not usually seen unless
there is injury
• Displacement of supinator fat stripe could
mean fractures of radial head and neck
• Change in shape or placement of anterior
fat pad may indicated joint effusion &
elbow injury
Elbow (lateral)
• ?elbow flexed 90 degrees
• ? True lateral position
• ?elbow joint space is open and radial
head superimposes coronoid process
• ? Radial tuberosity superimposed by
radius and not seen in profile
• ?elbow joint in center of field
Humerus(AP)
• ?true AP
• ?long axis aligned
• ?midshaft of humerus in center of
film
• ?shoulder and elbow joints & lateral
humeral soft tissue on film
Humerus (lateral)
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?mediolateral
?lateromedial
?long axis aligned
?midshaft in center of field