Upper Extremity Flashcards
Where is the central ray directed for the PA projection of the third digit?
Proximal interphalangeal joint of the third digit
For the lateral projection of the second through fifth digits of the hand, through which joint should the CR be directed?
Proximal interphalangeal joint
From the pronated position, how many degrees should the finger be rotated for a PA oblique projection of that finger?
45
Which projection of the wrist requires the radial styloid process to be superimposed over the ulnar styloid process?
Lateral Projection
Where is the CR directed for the PA projection of the hand?
To the third metacarpophalangeal joint
Which projection of the wrist requires the finger end of the cassette to be elevated at an angle of 20 degrees from horizontal?
PA axial (Stecher method)
This projection is often used to better visualize the scaphoid bone.
From the pronated position, how many degrees should the hand be rotated for the PA oblique projection?
45
Which positioning maneuver of the wrist opens the carpal interspaces on the lateral side of the wrist?
Radial flexion
For the AP projection of the forearm, which positioning step should be taken to prevent radial crossover?
Supinated the hand
This positioning helps maintain the proper alignment of the forearm bones.
How should the hand be positioned for the AP projection and for the lateral projection of the forearm?
AP projection: hand supinated; lateral projection: hand lateral
Which projection of the forearm requires the elbow to be flexed 90 degrees?
Lateral
Which projection of the elbow best demonstrates the radial head free of bony superimposition?
Lateral (external) oblique
With reference to the plane of the IR, how should the humeral epicondyles be positioned for the AP projection of the elbow?
Parallel
Which evaluation criteria indicates that the humerus was properly positioned for the AP projection?
The humeral head and greater tubercle are both seen in profile
Which positioning characteristic best indicates that the humerus was properly positioned for the AP projection?
The humeral epicondyles are parallel with the IR
Which projection of the elbow best demonstrates the olecranon process within the olecranon fossa and the coronoid process in profile?
Medial oblique
Which projection of the elbow best demonstrates the olecranon process in profile?
Lateral
Where do we center for an AP projection of the thumb?
Metacarpophalangeal joint
What projection of the thumb requires the patient to rotate the hand into extreme internal?
AP
Where do we center for a PA projection of the third digit?
At the proximal interphalangeal joint
What area is of primary interest if, for the PA oblique of the hand, the fingertips are allowed to rest on the IR?
Metacarpals
In which lateral projection of the hand are only the proximal phalanges superimposed?
Fan lateral
From the prone position, the wrist should be rotated ______ degrees for the PA oblique projection of the wrist.
45
What surface of the wrist should be in contact with the cassette for the routine lateral projection of the wrist?
Ulnar
What carpal bone is best demonstrated in the ulnar deviation view of the wrist?
Scaphoid/ navicular
How should the humeral epicondyles appear in the image of the lateral projection of the forearm?
Perpendicular
Which projection of the elbow shows the coronoid process in profile and the olecranon process within the olecranon fossa?
Medial oblique
How many AP projections are necessary to best demonstrate the elbow without distortion when an injury prevents full extension of the elbow?
2- AP Distal humerus and AP Proximal forearm
Why do we put the hand in a loose fist for the PA projection of the wrist?
To decrease OID under the bones of the wrist.
Why is it important for the ‘fat pads’ in the elbow to be well demonstrated on a lateral elbow projection?
Damage to the fat pad could indicate injury to the radial head that may not be visible in AP, Oblique, and lateral images.
Where should the central ray be directed for the PA projection of the wrist?
At the midcarpal area and perpendicular to the IR.
How does the placement of the IR for the PA axial projection of the scaphoid differ from the PA projection of the wrist?
For the Stecher method, the IR is raised 20 degrees on the finger side, while it is parallel to the table for a regular PA projection of the wrist.
Why do we perform an AP projection of the forearm rather than a PA?
An AP projection better demonstrates the radius and ulna next to each other, as they cross over in a PA view.
Why might the patient have to lean laterally in an AP projection of the elbow?
To eliminate any rotation in the forearm so that the radius and ulna are not superimposed.
