ARRT - American Registry of Radiologic Technologists Upper Extremity Procedures Questions and Answers

Question 1

A patient arrives in the emergency department with a traumatic injury to their elbow and is unable to extend it for a standard AP projection. To best demonstrate a potential fracture of the radial head, which specialized projection should be performed?

Accepted Answer

Axiolateral projection (Coyle method)

Answer

The Coyle method is a specific trauma projection used to evaluate the radial head and coronoid process when the patient cannot extend their elbow. It involves flexing the elbow 90 degrees and angling the central ray 45 degrees toward the shoulder, which projects the radial head free of superimposition.

Question 2

An AP oblique projection of the shoulder (Grashey method) is performed primarily to demonstrate which of the following?

Accepted Answer

An open glenohumeral joint space.

Answer

The primary purpose of the Grashey method is to place the glenoid cavity in profile, thereby demonstrating an open glenohumeral joint space. This is achieved by rotating the patient 35 to 45 degrees toward the affected side. This view is excellent for evaluating joint space narrowing associated with arthritis.

Question 3

A radiographer is performing a PA projection of the wrist for a suspected scaphoid fracture. Which specific positioning maneuver is critical to best visualize the scaphoid bone free of foreshortening and superimposition?

Accepted Answer

Ulnar deviation

Answer

Ulnar deviation of the wrist elongates the scaphoid and opens the intercarpal spaces, particularly around the scaphoid. This movement corrects the natural foreshortening of the scaphoid that occurs in a neutral PA position, providing a clearer view for fracture assessment.

Question 4

Which of the following upper extremity projections is performed to evaluate for a suspected dislocation of the shoulder by demonstrating the relationship of the humeral head to the glenoid fossa in a true lateral perspective of the scapula?

Accepted Answer

PA oblique projection (Scapular Y)

Answer

The PA oblique (Scapular Y) projection provides a lateral view of the scapula. The 'Y' is formed by the acromion, coracoid process, and the body of the scapula. The humeral head should be superimposed over the junction of the 'Y'. This view is essential for determining the direction (anterior or posterior) of a shoulder dislocation.

Question 5

A trauma patient requires a lateral projection of the proximal humerus but cannot abduct their arm. The technologist decides to perform a transthoracic lateral (Lawrence method). What is the proper positioning for the patient's uninjured arm?

Accepted Answer

Raised above the head.

Answer

For the transthoracic lateral projection, the uninjured arm must be raised above the head. This elevates the uninjured shoulder, preventing its superimposition over the proximal humerus of the injured side, which is being imaged through the thorax.

ARRT - American Registry of Radiologic Technologists Practice Test

ARRT - American Registry of Radiologic Technologists Practice Test

ARRT - American Registry of Radiologic Technologists Upper Extremity Procedures Questions and Answers