forearm and elbow
What is BEST demonstrates on an AP oblique projection of the elbow with medial/internal rotation?
coronoid process of ulna is in profile
coronoid process belongs to which bone
ulna
olecranon process belongs to which bone
ulna
Why must an AP and not a PA projection be performed for the forearm?
If a PA projection would be performed, the radius would cross over the ulna superimposing the bones. In an AP projection of the forearm, the radius and ulna are nicely separated demonstrating both of the bones well.
What is the significance of the elbow being in a true 90 degree flexion for the lateral projection of the elbow and forearm?
If true 90 degree flexion the posterior fat pad should not be visible. IF posterior fat pad is seen with true 90 degree flexion then this is evidence of potential injury.
What are the two reasons for flexing the elbow at a true 90 degrees for the lateral image?
To place the olecranon process in profile The elbow fat pads are least compressed at 90 degrees - partial or complete flexion elevates the posterior fat pad simulating joint pathology
What can be done to image the elbow if the patient is unable to fully extend their elbow? Explain procedure.
Two images must be taken with partial flexion. One with the forearm and elbow on same plane and another with shoulder and elbow on same plane
The head of the radius articulates with what specific anatomy of the distal humerus?
capitulum
What positioning maneuver will ensure that the wrist and elbow joints will be open without distortion on the AP projection of the forearm?
lower shoulder to be on the same plane as wrist and elbow
Which fat pad/stripe is located deep within the olecranon fossa and NOT visible on a normal elbow?
posterior fat pad
What is BEST demonstrated on the AP oblique projection of the elbow with lateral/external rotation?
radial head, neck, and tuberosity are free of superimposition
What is the position of the radial tuberosity on a properly positioned lateral projection of the forearm and elbow?
radial tuberosity will be facing/pointing anteriorly
3 fat pads
supinator fat stripe posterior fat pad anterior fat pad
What positioning criteria must be met to ensure a true AP position of the elbow for the AP projection of the forearm and elbow?
the humeral intercondycondylar plane is parallel with the IR
The ulna articulates with what specific anatomy of the distal humerus?
trochlea