RAD 101 Unit 6 Positioning of the Forearm, Elbow, and Distal Humerus

Positioning Considerations

-40 inches (100 cm) minimum SID

-Four-sided collimation when possible

-Long axis of part to long axis of IR

-Marker visible

kVp range for the Forearm, Elbow, and Humerus

65-75

AP Forearm

-Hand and arm extended with palm up

~Entire arm on same plane

-Include both wrist and elbow joints

-Humeral epicondyles same distance from IR

-CR at mid forearm

AP Forearm Evaluation Criteria

-Carpals to distal humerus included

-No rotation- Humeral

epicondyles are in profile

-Slight superimposition of radial head, neck and tuberosity over proximal ulna

Lateral Forearm

-Elbow flexed 90 degrees

-Entire arm on same plane

-Wrist and hand true lateral position (upper extremity position)

-CR to midforearm

Lateral Forearm- Evaluation Criteria

-Carpals and distal humerus included

-Elbow flexed 90°

-No rotation-Head of ulna superimposed over radius

-Humeral condyles superimposed

-Radial head superimposed over coronoid process

AP Elbow-Fully Extended

-Elbow fully extended with hand supinated

-Entire arm on same plane

-Epicondyles parallel to IR

-CR to mid-elbow joint

Two Partially Flexed AP Projections (When Elbow Cannot Be Fully Extended)

-Humerus parallel to IR

-Forearm parallel to IR

Humerus parallel to IR

CR perpendicular to mid-elbow

Forearm parallel to IR

CR perpendicular to mid-elbow

AP extended

Humerus parallel

Forearm parallel

AP Projections of Elbow anatomy will be obscured the

more the elbow is flexed

Oblique Projections of Elbow

-Medial oblique

(45° internal (medial) rotation

-lateral oblique

(45° external (lateral) rotation

Medial oblique (internal)-45 degrees of the Elbow

-Hand is pronated

-Rotate epicondyles and anterior surface of elbow is 45 degrees to IR

-"leaning" on medial epicondyle

Lateral oblique (external)- 45 degrees of the Elbow

-Hand is supinated

-Rotate epicondyles and anterior surface of elbow is 45 degrees to IR

-"leaning on lateral epicondyle

Evaluation Criteria: lateral/external oblique elbow

-Radial head, neck, and tuberosity free of superimposition over ulna

-Lateral epicondyle and capitulum in profile

Evaluation Criteria: medial/internal oblique of the elbow

-Coronoid process in profile

-Radial head and neck centered over ulna

-Trochlea and medial epicondyle in profile

-Olecranon process seated in the fossa

Lateral (lateromedial projection) Elbow

-Elbow flexed 90°

-Humerus and forearm parallel on same plane

-Hand and wrist in lateral position, thumb side up

-Interepicondylar plane perpendicular to IR

-CR at mid elbow joint or 1 ½ inches medial to olecranon process

Evaluation Criteria: lateral elbow

-Three concentric arcs visible

-Olecranon process in profile

-½ of radial head superimposed over coronoid process

Radial head projections

-All four projections are done with the elbow in the lateral position

-CR is at radial head or 1" distal to the lateral epicondyle

-The hand position changes for each projection

-Different portions of the radial head are demonstrated

Radial Head Lateromedial Projections 1

-Hand supinated—maximum external rotation

-Radial head slightly anterior (facing away from ulna)

Radial Head Lateromedial Projections 2

-Hand lateral- thumb up

-Radial tuberosity superimposed over shaft of radius

Radial Head Lateromedial Projections 3

-Hand pronated

-Radial tuberosity slightly posterior (pointing towards ulna)

Radial Head Lateromedial Projections 4

-Hand internal rotation—maximum internal rotation

-Radial tuberosity posterior in profile (pointing towards ulna)

Radial Head Lateromedial Projections 5

-Trauma Axial (aka Coyle Method)

-Hand pronated

-Cephalic tube angle 45 degrees toward the shoulder

AP Humerus Projection

-Include both shoulder and elbow joints

-May be done erect or supine

-Shoulder and proximal humerus in contact with IR

-Abduct arm slightly away from body

-Supinate hand so that humeral epicondyles parallel with IR

-CR to midhumerus

Evaluation Criteria: AP humerus

-Entire humerus demonstrated

-Greater tubercle in profile laterally

-Minimal superimposition of humeral head over glenoid

-Medial and lateral epicondyles in profile

Lateromedial Humerus Projections

-Patient back to IR

-Shoulder and proximal humerus in contact with IR

-Interanlly rotate arm

-Epicondyles perpendicular to IR

-CR to midhumerus

Mediolateral Humerus Projection

-Patient facing IR

-Oblique 20-30 degrees to bring affected humerus in contact with IR

-Flex elbow 90 degrees

-CR at midhumerus

Evaluation Criteria: lateral humerus

-Entire humerus demonstrated

-Lesser tubercle in profile medially

-Humeral epicondyles superimposed

Horizontal Beam Transthoracic Lateral Humerus (Trauma)

-Affected arm against IR

-Affected arm is in neutral position and relax shoulder

-Unaffected limb raised over head.

-Lift unaffected shoulder if possible

-CR to mid aspect of involved humerus

Evaluation Criteria: Horizontal Beam Transthoracic Lateral Humerus (Trauma)

-Include entire humerus

-No superimposition of unaffected humerus

-Affected humerus visualized anterior to T-spine