image evaluation chapter 3 critique of upper extremity
TRANSCRIPT
Image EvaluationImage EvaluationChapter 3Chapter 3
Image EvaluationImage EvaluationChapter 3Chapter 3
Critique of Upper ExtremityCritique of Upper Extremity
Hand (PA)• 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