Position Upper Extremity Imaging - ARRT Radiography Exam

What is the CR location for an AP hand projection?

Third metacarpophalangeal (MCP) joint. Centering at this joint captures the entire hand with balanced exposure and minimal distortion of metacarpals and phalanges.
What is the CR location for an AP elbow projection?

Mid-elbow joint (about $2.5$ cm distal to the midpoint of epicondyles). This location targets the joint space precisely, accounting for the slight distal position relative to epicondyles.
What is the CR location for an AP forearm projection?

Midshaft of the forearm. Centering midshaft captures the entire forearm length, including both joints, with balanced exposure in AP projection.
Which projection is routine to evaluate a suspected scaphoid fracture of the wrist?

PA wrist with ulnar deviation (scaphoid view). This view elongates the scaphoid bone, minimizing overlap with adjacent carpals to better visualize potential fractures.
Which routine wrist projection best demonstrates the distal radioulnar joint space?

AP oblique wrist with medial (internal) rotation. Medial rotation in AP oblique separates the distal radius and ulna, providing clear visualization of the joint space.
Which projection is performed to evaluate elbow effusion and fat pads after trauma?

Lateral elbow projection (for anterior and posterior fat pads). The lateral view elevates fat pads in effusion, making anterior and posterior pads visible for trauma assessment.
What is the central ray (CR) location for a PA wrist projection?

Midcarpal area. Centering the CR here ensures optimal visualization of carpal bones and wrist joint spaces in the PA projection.
Which elbow projection is used to best demonstrate the radial head free of superimposition?

AP oblique elbow with lateral (external) rotation. Lateral rotation projects the radial head away from the ulna, allowing evaluation without bony overlap.
Which projection is used for an acute elbow injury when the patient cannot extend the elbow?

AP partial flexion and lateral partial flexion (Coyle method as needed). Partial flexion views accommodate limited extension, while Coyle method adapts for radial head visualization in injury.
Which elbow projection best demonstrates the coronoid process of the ulna?

AP oblique elbow with medial (internal) rotation. Medial rotation profiles the coronoid process, separating it from the radius for clear visualization in the oblique view.
Which forearm projection demonstrates the radius and ulna superimposed?

Lateral forearm projection. The lateral view superimposes proximal radius over ulna and distal ulna over radius, profiling the forearm accurately.
Which positioning method is used for a true lateral finger (digits 2 to 5) projection?

Lateromedial with the finger fully extended. Lateromedial positioning with extension profiles the finger laterally, showing joint spaces and soft tissues without overlap.
Which positioning requirement defines a true lateral elbow projection?

Elbow flexed $90^\circ$ ; humeral epicondyles perpendicular to IR. 90° flexion with perpendicular epicondyles ensures true lateral alignment, profiling the olecranon and joint spaces.
Which hand projection best demonstrates the phalanges free of superimposition?

PA oblique hand (lateral rotation). Lateral rotation separates the phalanges, reducing overlap for clear evaluation of individual bones and joints.
What is the positioning requirement for a true lateral hand projection?

Fingers extended; metacarpals superimposed. Extending fingers and superimposing metacarpals ensure a true lateral view, profiling interphalangeal joints without distortion.
What is the hand and wrist positioning requirement for a true lateral wrist projection?

Thumb up; radius and ulna superimposed. This positioning aligns the wrist in true lateral, ensuring superimposition of radius and ulna for accurate side profile imaging.
What is the CR location for an AP thumb projection?

First metacarpophalangeal (MCP) joint. Centering at the first MCP joint ensures comprehensive coverage of the thumb's phalanges and metacarpal in AP view.
What anatomy must be included on all forearm projections?

Elbow and wrist joints. Including both joints ensures complete evaluation of the forearm bones, from proximal radius/ulna to distal articulations.
What anatomy must be included on all humerus projections?

Shoulder and elbow joints. Including both joints captures the entire humerus, allowing evaluation of shaft, articulations, and potential fractures.
What is the CR location for a PA finger (digits 2 to 5) projection?

Proximal interphalangeal (PIP) joint. Centering at the PIP joint provides optimal exposure and detail for the phalanges and interphalangeal joints in PA view.
Which humerus projection requires the epicondyles parallel to the IR for a true AP view?

AP humerus projection. Parallel epicondyles in AP ensure the distal humerus is not rotated, providing a true anterior-posterior view.
What is the positioning requirement for an AP forearm projection?

Hand supinated; humeral epicondyles parallel to IR. Supination with parallel epicondyles aligns the forearm in true AP, separating radius and ulna for clear joint visualization.
Which finger projection is preferred to show the joint spaces open and phalanges in profile?

PA finger projection. The PA view aligns phalanges parallel to the image receptor, opening joint spaces and profiling bones effectively.
Which projection is used to demonstrate the carpal canal (tangential wrist)?

Tangential (Gaynor-Hart) carpal canal projection. This tangential view projects the carpal tunnel axially, visualizing the pisiform, hamate hook, and tunnel contents clearly.
Which thumb projection best demonstrates the trapezium and first carpometacarpal joint?

AP oblique thumb (lateral rotation). Lateral rotation in AP oblique minimizes overlap, clearly demonstrating the trapezium and first CMC joint structures.

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