Lecture 2: Image Critique Upper Extremity Flashcards
T/F
There is more soft tissue and concavity on anterior surface of the finger
True
What should be seen on an image of a PA finger?
-Equal soft tissue
-Midpoint concavity the same on both sides of phalanges
-Open joint spaces
What errors have been made in this image of the PA finger?
Lateral side of the digit is obliqued with the thumb away from the IR
What digit is this?
Right index
What errors have been made in this image of the PA finger?
No joint space visible, right index finger is flexed
T/F
There is better joint space visibility when doing an AP projection for unextendable digits
True
What should be seen on an image of a lateral finger?
-Open interphalangeal joints
-Superimposed heads of proximal and middle phalanges
-Fingernail in profile
-No overlap of adjacent digits
What errors have been made in this image of the lateral finger?
-Finger is not parallel to the IR (tip down too low)
-Marker overtop of the finger
What error(s) have been made in this image of the lateral finger? How can this be corrected?
-Fingers are not out of the way
-External rotation needed to align the 2nd metacarpal over the 4th
Is this image repeatable?
No; because fracture is visualized
T/F
The second metacarpal is the longest
True
What corrections should be made to this image of the lateral finger?
More internal rotation needed
What should be seen on an image of the PA thumb?
-Equal soft tissue
-Midpoint concavity the same on both sides of phalanges
-Open joint spaces
-Long axis of thumb in line with central ray
-Include trapezium
What error(s) have been made? What could be done to correct this?
Slightly obliqued; externally rotate the wrist to fix
What error(s) have been made? How could this be corrected?
-Distal joint space is not open
-Flatten thumb against IR to fix
How can you visualize all four joints spaces of the trapezium?
By raising the elbow
What projection is this?
AP thumb
What should been seen in an image of the lateral thumb?
-Open interphalangeal joints
-Superimposed heads of proximal phalanx
-Fingernail in profile
-Include trapezium
-Abduct thumb
What correction(s) if any, need to be made to this image of the lateal thumb?
-Internal rotation of the thumb needed
What correction(s) if any, need to be made?
Thumb needs to be abducted slightly because the soft tissue is superimposed
What should be seen on an image of the PA hand?
-No rotation
-Equal distance between MCP heads
-Thumb is in a PA oblique position
-5th phalanges lined up with metacarpal
-Open MCP and IP joint spaces
What error(s) have been made to this image of the PA hand?
-Hand externally rotated
-Looks like oblique due to the metacarpal spaces getting closer together and concavity of the phalanges seen
What error(s) have been made in this image of the PA hand?
-Hand is not flat (fingers flexed)
-Hand slightly obliqued
What error(s) have been made in this image of the PA hand?
-5th phalange not in line with the 5th metacarpal (over abducted)
-Joint space closed on digits due to beam divergence from over abducted digits
What should be seen in an image of the PA Oblique hand?
-Open MCP and IP joint spaces
-Overlap of MC heads 3-5
-No overlap between 2nd and 3rd MC heads
-Slight space between 4th and 5th metacarpal at the midshaft
What error(s) have been made in this image of the PA oblique hand?
-Poor centering; too much on wrist and cutting off middle tip of finger
lol that’s the amount in practice that they want on the wrist
What will be visualized if the hand is underobliqued in a PA oblique?
Space bigger between the metacarpal heads, and larger spaces between the metacarpal shaft
What could have been done to better visualize the joint spaces?
Fingers need to be more extended to visualize the joint spaces
What corrections need to be made to this PA oblique?
-Fingers need to be more extended to visualize joint space
(good oblique)
What error(s) have been made in this image of the PA oblique?
Over obliqued (too externally rotated)
What should be seen in an image of the fan lateral?
-2nd – 5th metacarpals superimposed
-IP joints are open
-2nd – 5th digits are separated
Wht error(s) have been made in this image of the fan lateral?
None
What error(s) have been made in this image of the fan lateral? What could be done to correct this?
-Not in a good lateral
-Metacarpals are not superimposed; needs more external rotation
Where should the styloid processes be in a PA wrist image?
Styloid processes are at the extreme edges
What joint spaces need to be open in a PA wrist?
-Scapholunate joint
-Radioulnar joint
-CMC joints
Where should the pisiform be in relation to the triquetrum on in a PA wrist
Pisiform is positioned outside of ulnar border of the triquetrum
How can you visualize the radiocarpal joint space?
11 degree angle cephalad
What border is the red and yellow line on the radius?
Red: Anterior margin
Yellow: Posterior margin
What oblique of the wrist best demonstrates the pisiform?
AP Oblique
What oblique is the best to to demonstrate the scaphoid?
PA oblique
What error(s) have been made in this image of the PA wrist?
-Wrist is obliqued (thumb is off the IR)
How could CMC joint space be better visualized?
Flatten the wrist
What carpal bone is visualized?
Trapezium
What radiographic sign is visable with radial deviation in the wrist?
Signet ring sign
What is present?
Radial deviation OR Ulnar deviation?
Radial deviation
T/F
In a PA wrist, having the proximal forearm higher than distal forearm will cause excessive foreshortening of the scaphoid
True
T/F
Ulnar deviation will cause excessive forshortening of the scaphoid.
False; radial deviation will cause excesive forshortening of the scaphoid
What happens with wrist extension to the scaphoid and CMC joints in a PA wrist?
-Less foreshortening of the scaphoid
-CMC joint spaces closed
How should the pisiform and scaphoid be aligned in a lateral wrist?
Anterior part of distal scaphoid is nearly aligned with anterior part of pisiform
T/F
In a lateral wrist, the radius and ulnar should be superimposed.
True
Label the blue, purple and red lines
Red: Trapezium
Purple: Scaphoid
Blue: Pisiform
If you are doing lateral wrist, what do hit first; scaphoid or pisiform?
Scaphoid
How much of the radial tuberosity should be overlaped on the ulna in an AP elbow?
50% of the radial tuberosity should be overlapping on the ulna
How much should the radial head be overlapped over the ulna in an AP elbow?
0.25” (0.6 cm) overlap of radial head on ulna
What joint space should be open in an AP elbow?
Capitulum-radial joint space is open
T/F
In an AP elbow the radius and ulna should be parallel
True
What error(s) have been made in this image of the AP elbow?
Too much overlap (thumb has come off the IR)
What error(s) have been made in this image of the AP elbow?
Elbow too externally rotated
What projection is this?
Partial flexion elbow with forearm off IR
How should you image a child for a partial flexion elbow view?
Humorous parallel to the IR
How should you image an adult for a partial flexion elbow view?
Forearm parellel to the IR
What is the best way to demonstrate the radial head fracture?
AP External Oblique
What joint spaces need to be open for a AP External Oblique?
-Capitulum-radial joint space
-Radio-ulnar joint space
T/F
The radial head, neck, and radial tuberosity should be superimposed on the ulna in an AP External Oblique.
False; No overlap of radial head, neck, or radial tuberosity on ulna
What error(s) have been made in this image of the AP External oblique elbow? How could this be corrected?
-Radial head joint space not open
-Place forearm flat on the IR
What error(s) have been made in this image of the AP external oblique elbow?
Too externally rotated
What error(s) have been made in this image of the AP external oblique elbow?
-Not rotated enough
-Radioulnar joint space is not open
How much of the radial head should be superimposed on the ulna in an AP internal oblique?
¾ of the radial head is superimposed on ulna (min 75% of superimposition)
What position best demonstrates the coronoid process?
AP internal oblique
T/F
The trochlear notch is visible in an AP internal oblique of the elbow.
True
What error(s) have been made in this image of the AP internal oblique elbow?
-Not enough internal rotation
What error(s) have been made in this image of the AP internal oblique elbow?
None :)
yippie.
What structures should be aligned/superimposed in a lateral elbow?
-Capitulum and trochlea superimposed
-Articulating surfaces of radial head and coronoid process are aligned
What occurs to the fat pads if there is excessive flexion in a lateral elbow projection?
The SAIL sign/anterior fat pad is pushed back
What structure is seen first in a lateral elbow?
The radius
What corrective measures should be made to correct the mistakes made in this image?
Raise the hand, slight more flexion
How can you tell the difference between the medial and the lateral condyles of the elbow?
Medial side: Smooth continuous bump
Lateral side: Jutts in to form an abrupt angle
What corrective measure should be made in this image?
-Raise the elbow up/shoulder down
Label the red and the yellow lines:
Yellow: Medial
Red: Lateral
What corrective measure should be made for the lateral elbow?
-Raise the hand and raise the elbow up
What corrective measures should be made for this image?
-Hand down
-Elbow up
-Flex elbow more
-Center on the condyles
What is the corrective measure for this image?
Raise the hand, lower the elbow
Note the posterior fat pad, sail sign
What position should be done first in a shoulder series?
External rotation
(includes all of scapula and clavicle)
Where is the greater tuberosity and the humeral epicondyles in an external rotation shoulder?
-GT in profile on the lateral side
-Humeral epicondyles are parallel to IR
Where is the lesser tuberosity and the humeral epicondyles located in an internal rotation shoulder?
-Lesser tuberosity in profile medially
-Humeral epicondyles are perpendicular to IR
Where is the Greater tuberosities located in a neutral shoulder projection? Where are the humeral epicondyles?
-Anterior on the humeral head
-Humeral epicondyles at a 45 degree oblique
How can you image the subacromial space in the shoulder?
By using a caudad angle
What projection of the shoulder is this?
-External rotation
-Grade 3 AC separation, broken ribs, scapula
What projection is this?
Internal rotation shoulder
What projection is this?
Neutral rotation
In a glenoid projection, what should be superimposing the humeral head and by how much?
Coracoid process superimposes humeral head by 0.25” or 0.6 cm
What corrections need to be made to this image of the glenoid?
-Need to be obliqued more (ribs need to be closer to the joint space)
What correction needs to be made to this image of the glenoid?
Patient needs to be obliqued more
What space needs to be open in a lateral Y scap?
Subacromial space
Where should the humeral head be in a lateral Y scap?
In the middle of the Y
What error(s) have been made to this image of the Y scap?
Patient was obliqued too far
If an angle was need for a Y scap, and the patient was PA, what angle would you use, caudad or cephalad?
Caudad
What correction needs to be made for this image?
Patient needs to be obliqued more
Where should the lesser tuberosity be seen in axillary projection of the shoulder?
Lesser tuberosity in profile anteriorly
What is the best projection to confirm shoulder dislocations?
Axillary projection of the shoulder
Where should the coracoid process and the glenoid cavity be in relation to one another in an axillary projection?
Glenoid cavity lines up with lateral border of coracoid process
What should the angle between central ray and the side of the body be for an infrosuperior axial shoulder?
Angle between central ray and the side of the body: 30-35 degrees
In an infrosuperior axial view, what structure do we hit first?
The glenoid
What error(s) have been made in this image?
Angle between the body and central ray is too small
What corrections need to be made to this image of the AP glenoid?
-Patient needs to be more obliqued
-Axillary view needed
