Bontrager Chapter 4 - Forearm and elbow

Positioning considerations for all upper limbs

40" SID gonadal shielding collimation long axis of IR to long axis of part Patient ID and side marker visible

Elbow special projections

Trauma axial lateral (Coyle method)

Three Concentric Arcs of lateral elbow

Trochlear sulcus outer ridges of capitulum and trochlea trochlear notch of ulna

medial epicondyle

small projection on the medial edge of the distal humerus

AP elbow medial rotation xray

superimposed radius and ulna

Proximal radioulnar joint is what type of joint

trochoidal (pivot) type joint

Two Partially Flexed AP Projections(when elbow cannot be fully extended)

Humerus parallel and forearm parallel

Fracture

- Simple (closed) fx - Compound (open) fx (breaks through skin) - Comminuted fx (splintered or crushed) - Impacted fx (fragments driven into each other)

Trauma Axial Lateromedial Projections (Coyle Method) projection for radial head

1. Part position: elbow 90 degree flexion, hand pronated 2. CR: 45 degree angle toward the shoulder centered to the mid elbow joint

Lateral elbow projection

1. Patient Position: pt seated elbow flexed 90 degrees, drop shoulder 2. Part position: rotate hand and wrist into a true lateral position thumb side up, place support under hand and wrist to make sure forearm and humerus is parallel 3. CR: perpendicular to the mid elbow joint, approximately 4cm (1 ½ in ) medially to the posterior surface of the olecrenon process

AP Elbow—Fully Extended

1. Patient Position: seated with elbow fully extended 2. Part position: align w/long axis of IR, center elbow joint to center of the IR, may need pt to lean laterally to obtain a true AP, support hand to prevent motion 3. CR: perpendicular to the mid elbow joint, which is 2cm distal to the midpoint of the line between the epicondyles

Elbow oblique projection - For medial rotation

1. Patient Position: seated, shoulder and elbow on the same horizontal plane 2. Part position: pronate the hand and rotate arm until the distal humerus and the anterior surface of the elbow are rotated 45 degrees. For both positions palpate the epicondyles to determine if they are 45 degrees 3. CR: perpendicular to the mid elbow joint (2cm distal to the midpoint of the line between the epicondyles

Elbow oblique projection - for lateral rotation

1. Patient Position: seated, shoulder and elbow on the same horizontal plane 2. Part position: supinate the hand and rotate the entire arm so the distal humerus and and anterior surface of the elbow joint are 45 degrees to the cassette (pt will need to lean laterally) For both positions palpate the epicondyles to determine if they are 45 degrees 3. CR: perpendicular to the mid elbow joint (2cm distal to the midpoint of the line between the epicondyles

3 elbow fat pads

1. anterior fat pad 2. posterior fat pad 3. supinator fat pad-located anterior to the proximal radius

Elbow projections

AP Lat oblique Med oblique Lateral

Medial oblique criteria

Coronoid process in profile Trochlea and medial epicondyle in profile

Elbow joint in what type of joint

Ginglymus (hinge) type because it allows for flexion and extension

styloid process

Located at extreme distal ends of radius and ulna

The two beak-like processes on the proximal ulna

Olecranon and coronoid processes

Trauma Axial Lateromedial Projections (Coyle Method) projection for coronoid process

Part position: Elbow 80degree flexion CR: 45 degrees away from the shoulder into the mid elbow joint

Lateral oblique criteria

Radial head, neck, and tuberosity in profile Lateral epicondyle and capitulum in profile

trochlear sulcus

Smooth depressed center portion of the trochlea

coronoid tubercle

The medial margin of the coronoid process opposite the radial notch

Lateral elbow criteria

Three concentric arcs visible Olecranon process in profile Appropriate exposure factors

Trochlea

a smooth, grooved articular process shaped like a pulley

capitulum

articulates with head of radius

Radial notch

depression on the lateral side of the proximal ulna

ulnar notch

depression on the medial distal end of the radius, articulates with the head of the ulna

Criteria-AP Elbow

elbow joint visible and in center of the film, epicondyles seen in profile, olecrenon process seated in the olecrenon fossa if fully extended

Elbow Fat Pads and Stripes

only seen in the lateral position, elbow must be 90 degrees

lateral epicondyle

projection on the lateral side of the distal humerus above the capitulum

AP elbow no rotation

radias and ulna are partially superimposed

AP elbow xray

radius and ulna slightly superimposed

AP elbow, lateral rotation

separates radius and ulna

AP elbow lateral rotation xray

separates ulna and radius

AP elbow, medial rotation

superimposes the radius and ulna

Overall the elbow joint is a ---- (freely moveable) joint

synovial

Humeral condyle

the entire distal end of the humerus and includes two smooth elevations for articulation- trochlea on the medial side and capitulum on the lateral side