Elbow

Question 1

What are the routine views for an elbow?

Answer 1

BASIC ELBOW
AP Fully extended, 164
AP Partially flexed, 165
AP Oblique projection: Lateral (external) rotation, 164
Lateral, 166
SPECIAL
Acute flexion (Jones method), 169
Trauma axial laterals for radial head only (Coyle method), 170
Radial head laterals, 171 (not assessed)

Question 2

Explain the procedure for ap fully extended elbow radiograph.
CP
Pt position
What you should see…

Answer 2

• Centre point- mid elbow joint
• Elbow and shoulder should be on the same plane
• Patient should lean laterally until they’re in a true lateral position
• Both humeral epicondyles should appear in profile and not rotated
  Elbow joint space should be well opened

Question 3

What form of radiation protection do we give the patient?

Answer 3

Shielding: Place lead shield over abdo/pelvic area.

Sit patient along side table.

Question 4

For an AP partially flexed image, what are the two images to take?

And what should you see in each.

Answer 4

• AP view of a partially flexed elbow with the forearm in contact with IR.
  Note that the radial head is demonstrated in profile.
• Same patient with the partially flexed elbow in AP position with humerus in contact with IR. This produces a partially enface view of radial head providing a clearer demonstration of the comminuted fracture. This compromise view of the elbow but can be utilized to advantage with some types of radial head fracture.

Question 5

Purpose of a 45 degree oblique?

Answer 5

Purpose of 45o lateral oblique is to demonstrate radial head & radial neck free of superimposition & unobstructed demonstration of radioulnar joint

Question 6

Lateral Elbow Expected Image Criteria

Answer 6

1. Soft tissue margins demonstrated (this image is cropped)
2. Elbow flexed 90o with joint space open
3. Humerus epicondyles are superimposed
4. Olecranon process ulna is well-seen in profile
5. Radial tuberosity should appear in profile
6. (About ½ radial head should be superimposed on coronoid process of ulna)
7. Capitellum & trochlea of distal humerus should be seen concentric circles a true lateral

Question 7

There will generally be two basic corrections for lateral elbow malposition, what are they?

Answer 7

• raise hand/lower hand (external rotation/internal rotation of humerus)
• raise/lower elbow (adduct/abduct humerus)

Question 8

Explain the proximal radial line and what it should indicate/point too……

Answer 8

Proximal radial line should always bisect capitellum in any projection
Proximal radial line essentially points to the capitellum.

Question 9

what happens when the elbow is too externally rotated?

Answer 9

When elbow is too externally rotated, capitellum (side away from IR) rotates posteriorly.

Question 10

Error 1: Shoulder higher than elbow.

Explain and give solution

Answer 10

For a true lateral, shoulder should be at level of elbow. * If shoulder is higher than elbow, radius & capitellum will project onto ulna.
-Solution is either to lift table which will lift the elbow or to lower shoulder by placing patient on a smaller chair.

Question 11

Error 2: Wrist lower than elbow

Explain and give solution

Answer 11

The lateral structures (capitellum) and the radius will move anteriorly, while a medial epicondyle (and trochlea) will move posteriorly.

The wrist should be higher than elbow to compensate for normal valgus position of the elbow. (valgus: deformity involving oblique displacement of part of a limb away from the midline.The hand should be with the ‘thumb up’.

Question 12

Explain the anterior humeral line..

Answer 12

Anterior humeral line.A line drawn on lateral along anterior surface of humerus should pass through middle 1/3 of capitellum..