Forearm and elbow Positioning
For a true AP elbow, how should the patient be positioned?
Have the patient lean laterally until the humeral epicondyles and anterior surface of the elbow are parallel with the plane of the IR
What can be used in place of AP projection of the elbow when a patient cannot completely extend the joint?
AP elbow - Partial flexion position
How is the AP INTERNAL oblique elbow centered to the IR?
Center the elbow joint (1 inch below epicondyles) to the center of the IR longitudinally and transversely
How is the lateral elbow centered to the IR
Center the elbow joint (1 inch below the epicondyles) to the center of the IR longitudinally and transversely
What are the structures shown for an AP EXTERNAL oblique elbow projection?
Radial head, neck, and tuberosity projected free of the ulna
How is the elbow centered to the IR for an AP EXTERNAL oblique elbow projection
Center the elbow joint (1inch below humeral epicondyles) to the center of the IR longitudinally and transversely
How is the lateral forearm centered to the IR
Center the forearm to the center of the IR longitudinally and transversely
How is the AP forearm centered to the IR?
Center the mid shaft of the forearm to the center of the IR including appropriate joints longitudinally and transversely
What are the structures shown for the lateral elbow
1 Elbow joint 2. Distal arm 3. Proximal forearm
What are the structures shown for an AP elbow? (3)
1. AP elbow joint 2. Distal arm 3. Proximal forearm
Coyle method part position for coronoid process
1. Elbow flexed 80 degrees 2. Hand pronated 3. Direct the CR away from the shoulder at an angle of 45 degrees to the coronoid process; CR enters the joint at mid elbow
Coyle method part position for radial head
1. Elbow flexed 90 degrees 2. Hand pronated 3. Direct the CR toward the shoulder at an angle of 45 degrees to the radial head; central ray enters the joint at mid-elbow
What should be shown for a true lateral elbow?
1. Elbow flexed 90-degrees 2. Superimposed humeral epicondyles 3. Radial tuberosity facing anteriorly 4. radial head partially superimposing the coronoid process 5. olecranon process in profile
What are the structures shown for an AP projection of the forearm
1. Elbow joint 2. Radius and ulna 3. Proximal row of slightly distorted carpal bones
How is the patient positioned for this external oblique elbow.?
1. Extend the patient's arm in position for an AP projection 2. Center the midpoint of the IR to the elbow joint 3. Rotate the hand laterally to place posterior surface of the elbow at a 45-degree angle 4. The patients first and second digits should touch the table
What position do you need for a true lateral projection of the forearm
1. Flex the elbow 90 degrees 2. Thumb side of the hand must be up
What are the 4 radial head views
1. Hand supinated as much as possible 2. Hand lateral 3. Hand pronated 4. Hand internally rotated
How do you position a patient for the AP elbow DISTAL HUMERUS partial flexion position?
1. Humerus in the same plane with posterior surface resting on IR 2. Elevated forearm supported 3. Supinate hand if possible, and center IR to the condyles of the humerus
How do you position a patient for the AP elbow PROXIMAL FOREARM partial flexion position
1. Leaving the elbow flexed, place the dorsal surface of the forearm on the IR 2. Supinate the hand, if possible, and center the IR to the condyles of the humerus
What should be clearly shown for a true AP forearm?
1. Partially open elbow joint if the shoulder was placed in the same plane as the forearm 2. Open radioulnar joint space
What should be clearly shown for an AP elbow? (2)
1. Radial head, neck, and tuberosity slightly superimposed over the proximal ulna 2. Elbow joint open and centered to the central ray
What should be clearly shown for a true lateral position of the lateral forearm?
1. Superimposition of the radius and ulna at their distal end 2. Superimposition of he radial head over the coronoid process 3. Superimposed humeral epicondyles 4. Anterior facing radial tuberosity
What are the structures shown for a lateral forearm?
1. The bones of the forearm 2. Elbow joint 3. Proximal row of carpal bones
Why is it important to flex the elbow 90-degrees for a lateral projection of the elbow
1. The olecranon process can be seen in profile 2. The elbow fat pads are least compressed
What should be shown for a true AP Internal oblique?
45-degree medial rotation of the elbow: 1. Coronoid process in profile 2. Elongated medial humeral epicondyle 3. Ulna superimposed by the radial head and neck
What is the rotation for an AP EXTERNAL oblique elbow?
A 45-degree lateral rotation of the elbow
What is the rotation for an oblique AP INTERNAL oblique elbow
A 45-degree medial rotation
How is the hand positioned for a lateral elbow. Why?
Adjust the hand in the lateral position. To ensure the humeral epicondyles are perpendicular to the plane of the IR
Where and how is the CR directed for the AP elbow
Direct the CR perpendicular to the elbow joint (1 inch below epicondyles) to the center of the IR longitudinally and transversely
Where and how is the CR directed for an AP EXTERNAL oblique elbow
Direct the CR perpendicular to the elbow joint (1 inch below humeral epicondyle) to the center of the IR longitudinally and transversely
Where and how is the CR directed for an AP INTERNAL oblique elbow
Direct the CR perpendicular to the elbow joint (1 inch below humeral epicondyles) to the center of the IR longitudinally and transversely
How is the CR directed for an AP elbow PROXIMAL FOREARM partial flexion position
Direct the CR perpendicular to the elbow joint and long axis of the forearm to the center of the IR longitudinally and transversely
Where and how is the CR directed for the lateral elbow?
Direct the CR perpendicular to the humeral epicondyles to the center of the Ir longitudinally and transversely
How is the CR directed for an AP elbow DISTAL HUMERUS partial flexion position
Direct the CR perpendicular to the humerus, passing through the elbow joint to the center of the IR longitudinally and transversely
How and where is the CR directed for a lateral forearm
Direct the CR perpendicular to the midpoint of the forearm to the center of the IR longitudinally and transversely
Where and how is the CR directed for an AP forearm?
Direct the CR perpendicular to the midpoint of the forearm to the center of the IR longitudinally and transversely
How is the AP elbow centered to the IR?
Extend the elbow, supinate the hand, and center the IR to the elbow joint (1 inch below humeral epicondyles) longitudinally and transversely
Should the elbow be bent or extended for an AP projection of the elbow?
Extended to prevent superimposition
When is an AP elbow partial flexion position used?
In place of the AP projection of the elbow when patient cannot completely extend the joint
Lead apron
Or a piece of lead rubber should be placed over reproductive organs for radiation protection
How do you find the elbow joint?
Palpate the lateral and medial epicondyles of the humerus
How do you get an open elbow joint for an AP projection of the forearm?
Place the shoulder in the same plane as the forearm
How should the arm be positioned for a radial head view
Position the elbow at 90 degrees
How do you clear the coronoid process of the radial head for an AP INTERNAL oblique elbow
Pronate the hand, and adjust the elbow to place it's anterior surface at 45 degrees
What two images are needed for the AP elbow partial flexion position (distal humerus)
Requires distal humerus and proximal forearm to be imaged separately
Why should the arm and shoulder be at the same plane for an AP elbow?
So there is no distortion of the elbow joint
What should be done if a patient cannot fully extend the elbow for a medial and lateral oblique projection
The Coyle (axiolateral) method should be used
What is the main structure shown for an AP INTERNAL oblique elbow projection?
The coronoid process of the ulnar head projected free of superimposition
How should the elbow be positioned for a lateral elbow projection
The elbow should be flexed 90-degrees for a true lateral elbow projection
How is the hand positioned for an AP INTERNAL oblique elbow? Why?
The hand is rotated internally, or pronated This degree of obliquity usually clears the coronoid process of the radial head
Is the hand pronated or supinated for an AP elbow? Why?
The hand is supinated for an AP elbow to prevent rotation of the bones of the forearm
What position should the hand be in for an AP projection of the forearm. Why?
The hand should be supinated. Pronation of the hand crosses the radius over the ulna at its proximal third and rotates the humerus medially - resulting in an oblique projection of the forearm
How do you position for supine position for trauma CORONOID PROCESS?
The horizontal central ray is directed caudal at an angle of 45 degrees to the coronoid process, entering the joint at mid-elbow
How do you position for supine position for trauma RADIAL HEAD?
The horizontal central ray is directed cephalad at an angle of 45 degrees to the radial head, entering the joint at mid-elbow
Why must the thumb side of the hand be up for a lateral projection of the forearm
The thumb side must be up to place the wrist in true lateral position
Coyle Method
This projection was devised for obtaining images of the radial head and coronoid process on patients who cannot fully extend the elbow for medial and lateral oblique projection. - It is particularly useful in imaging a traumatized elbow
Why must the elbow be flexed 90 degrees for a lateral forearm?
To rotate the ulna to the lateral position
What happens there is injury around the joint for a lateral position
When injury to the soft tissue around the elbow is suspected, the joint should be flexed only 30 or 35 degrees
How do you know if the patient's elbow is in a true AP EXTERNAL 45-degree position
When proper lateral rotation is achieved, the patient's first and second digits should touch the table
Is there any superimposition for the AP elbow?
Yes: Radial head, neck, and tuberosity are slightly superimposed over the proximal ulna
