Chapter Objectives

16. Identify which structures are best seen with each routine and special projection of the upper limb.

AP forearm- entire radius and ulna. proximal row of carpals and distal humerus.

Lateral Forearm-Lateral radius and ulna, proximal row of carpal bones, elbow and distal end of humerus.

AP Elbow- Distal humerus, elbow joint and proximal radius and ulna.

Acute Flexion Elbow- Distal humerus or proximal forearm.

AP Oblique Lateral Rotation- Distal humerus and proximal radius and ulna

AP Oblique Medial Rotation-Distal humerus and proximal radius and ulna.

18. Identify and apply the exposure conversion chart for various sized of plaster and fiberglass casts.

Small to medium dry plaster cast- Increase 5-7 kVp

Large or wet plaster cast- Increase 8 to 10 kVp

Fiberglass cast- increase 3-4 kVp

19. List the three radiographic criteria for a true lateral elbow position.

Distal humerus and proximal forearm, olecranon process and soft tissues and fat pads visable.

Elvow joint flexed at a 90 degree angle. Olecranon orocess visualized in profile.

Three concentric arcs of the trochlear sulcus, double ridges of the capitulum and trochlea and the humeral epicondyles occurs.

20. Given various hypothetic situations, identify the correct modification of position, exposure factors or both to improve the radiographic image.

No marker present. Not at a true 90-degree angle. Concentric arches of trochlear sulcus more oval shaped and not rounded. The olecranon process is not moved into the olecranon fossa. Sail signs present indicating joint effusion. Double ridges of the capitulum and trochlea not present. CR is up too far. Pt may not be able to open arm fully. Alternate partial flexion with two views may be needed.