Hand and wrist injuries are among the most common reasons patients present for radiographic examination in emergency departments, urgent care centers, and outpatient orthopedic clinics. From a simple fall onto an outstretched hand (FOOSH injury) to suspected scaphoid fractures in young athletes, the radiologic technologist's ability to produce diagnostic-quality images of the hand, wrist, and digits directly impacts patient outcomes. A poorly positioned hand series can miss a subtle fracture, delay treatment, or lead to unnecessary repeat exposures — and no technologist wants to explain to a patient why they need a third image of an already painful injury.
This comprehensive guide covers every standard projection of the hand, wrist, and fingers that you will encounter in clinical practice and on the ARRT radiography registry exam. We cover positioning steps, centering points, collimation boundaries, evaluation criteria, and the common errors that separate a good image from a great one. Whether you are a first-year student preparing for clinical rotations or a seasoned technologist looking for a refresher, this article will sharpen your positioning skills.
This article covers the standard hand series (PA, PA oblique, lateral), wrist series (PA, lateral, PA oblique), finger and thumb projections (PA, oblique, lateral for each digit), and special views including the scaphoid series, Norgaard (ball-catcher's) view, and carpal tunnel views. We also address pediatric modifications and trauma considerations.
Before positioning any part of the upper extremity, you must be comfortable with the underlying anatomy. The hand and wrist comprise 27 bones: 8 carpal bones in the wrist, 5 metacarpals in the palm, and 14 phalanges in the fingers (3 each for digits 2–5, 2 for the thumb). Knowing the bony landmarks helps you center accurately and evaluate your images for completeness.
Proximal row (radial to ulnar): Scaphoid (carpal navicular) — the most commonly fractured carpal bone, Lunate — frequently dislocated, Triquetrum, and Pisiform (a sesamoid bone sitting on the triquetrum). Distal row: Trapezium, Trapezoid, Capitate (the largest carpal bone), and Hamate (with its distinctive hook).
A helpful mnemonic for the carpal bones (proximal row then distal row): "So Long To Pinky, Here Comes The Thumb" — Scaphoid, Lunate, Triquetrum, Pisiform; Trapezium, Trapezoid, Capitate, Hamate.
Which carpal bone is most commonly fractured? The scaphoid. The scaphoid spans both rows of carpal bones, making it vulnerable during falls onto an outstretched hand. Because of its retrograde blood supply, scaphoid fractures have a high rate of nonunion and avascular necrosis (AVN), making early and accurate radiographic diagnosis critical. This is a high-yield topic on every ARRT registry exam.
The routine hand series consists of three projections: posteroanterior (PA), PA oblique, and lateral. These three views provide orthogonal visualization of all phalanges, metacarpals, and the visible carpal bones, allowing the radiologist to evaluate fractures, dislocations, foreign bodies, and arthritic changes.
Positioning: The patient is seated at the end of the table with the affected arm extended. The hand is placed palm-down (pronated) on the IR with the fingers slightly separated. The central ray (CR) is directed perpendicular to the IR, entering at the third metacarpophalangeal (MCP) joint. The IR is centered to the same location.
Technical Factors: 50–60 kVp, 2–4 mAs (for a DR system), small focal spot, 100 cm SID. No grid for hands (extremity technique rarely requires a grid unless the part measures over 10 cm).
Evaluation Criteria:
When positioning a patient with a painful or deformed hand, use a sponge cushion to support the forearm and elevate the wrist, allowing the hand to lie flat without the patient having to force the palm down. For suspected fractures, never force the hand into position — work with the patient's limited range of motion and document any positioning compromises.
Positioning: From the PA position, the hand is rotated externally (laterally) approximately 45 degrees onto the ulnar side, with the fingers slightly spread and supported by a radiolucent wedge or sponge. The thumb remains in a natural, relaxed position. The CR enters at the third MCP joint perpendicular to the IR.
What It Shows: The oblique projection profiles the metacarpal shafts and phalanges with less superimposition than the PA view. It is particularly valuable for evaluating metacarpal neck and shaft fractures, as well as the radial and ulnar aspects of the phalanges.
Common Error: Insufficient rotation (< 30 degrees) or excessive rotation (> 60 degrees) reduces the diagnostic value. The goal is approximately 45 degrees of external rotation — enough to separate the metacarpal shafts without creating excessive foreshortening.
Positioning: From the PA position, the hand is rotated externally so the lateral aspect rests on the IR (thumb side up). The fingers are spread in a "fan" pattern to minimize superimposition. The CR enters at the second MCP joint (proximal phalanx of the index finger), perpendicular to the IR.
What It Shows: The lateral view demonstrates the anterior-posterior relationships of the phalanges and metacarpals. It is essential for detecting volar or dorsal displacement of fracture fragments, which is not visible on PA or oblique views.
The wrist series is one of the most frequently ordered extremity exams. Accurate positioning is critical because subtle wrist fractures (scaphoid, lunate, distal radius) can be easily missed with suboptimal technique.
Positioning: The patient sits alongside the table with the affected arm extended. The hand is pronated (palm down) with the wrist centered to the IR. The fingers are gently flexed (clenched fist position) to bring the wrist closer to the IR. The CR is directed perpendicular to the IR, entering at the midcarpal area (approximately at the midpoint of the wrist joint, level with the radiocarpal articulation).
Evaluation Criteria:
On a true PA wrist, the radial styloid process projects distal to the ulnar styloid process by approximately 8–10 mm. If both styloids appear level, suspect rotation. Additionally, the distal articular surface of the radius has a normal volar tilt of about 10–15 degrees and a radial inclination of about 22–25 degrees — important measurements when evaluating distal radius fractures.
Positioning: From the PA position, the wrist is rotated externally 90 degrees so the ulnar side contacts the IR. The wrist and hand form a straight line (no flexion or extension). The fingers may be flexed slightly for comfort. The CR enters at the radiocarpal joint (palpable just distal to the radial styloid), perpendicular to the IR.
Critical Evaluation: In a true lateral wrist, the distal radius, lunate, capitate, and third metacarpal should be aligned along a central axis — this is the DISI/VISI alignment assessment. The radius and ulna should be superimposed distally. The palmar surface of the pisiform should be visible. Any step-off or angulation at the radiocarpal joint suggests a fracture or dislocation.
Positioning: From the PA position, the wrist is rotated externally approximately 45 degrees onto the ulnar side. The CR enters at the midcarpal area. This projection is excellent for evaluating the radial side of the carpus, the scaphoid waist, and the trapezium-trapezoid articulation.
| Projection | Centering Point | CR Angle | SID | Key Anatomy Shown |
|---|---|---|---|---|
| PA Hand | 3rd MCP joint | 0° (perpendicular) | 100 cm | All phalanges, metacarpals, carpals |
| PA Oblique Hand | 3rd MCP joint | 0°, hand rotated 45° | 100 cm | Metacarpal shafts, phalangeal profiles |
| Lateral Hand (Fan) | 2nd MCP joint | 0° | 100 cm | AP relationship of phalanges/metacarpals |
| PA Wrist | Midcarpal area | 0° | 100 cm | Radiocarpal joint, intercarpal spaces |
| Lateral Wrist | Radiocarpal joint | 0° | 100 cm | Distal radius, lunate-capitate alignment |
| PA Oblique Wrist | Midcarpal area | 0°, wrist rotated 45° | 100 cm | Scaphoid, trapezium, radial carpus |
| Scaphoid (Ulnar Deviation) | Scaphoid | 0° or 10° proximally | 100 cm | Scaphoid in full longitudinal profile |
| Norgaard (Ball-Catcher's) | Midcarpal (both hands) | 0° | 100 cm | MCP joints (rheumatoid erosions) |
The scaphoid series is a dedicated set of projections designed to optimally visualize the scaphoid bone. Because scaphoid fractures often present with normal findings on a routine 3-view wrist series, dedicated scaphoid views are essential when there is clinical suspicion (snuffbox tenderness, mechanism of FOOSH).
Positioning: The patient's hand is pronated in the PA position. The wrist is actively deviated toward the ulnar side (little finger side). The patient may be asked to make a fist, which further extends the scaphoid. The CR enters at the scaphoid (located in the anatomical snuffbox region, just distal to the radial styloid). Some protocols add a 10-degree proximal CR angulation.
Why This Works: Ulnar deviation moves the scaphoid away from the radius and into a more elongated, longitudinal position, reducing bony superimposition and allowing the waist of the scaphoid to be evaluated in profile.
Some departments include additional projections as part of the scaphoid series:
When a patient presents with snuffbox tenderness and a negative initial 3-view wrist series, do not clear the scaphoid. Place the wrist in ulnar deviation and repeat. If still negative but clinical suspicion remains high, the standard of care is to immobilize the wrist and repeat radiography in 10–14 days. At that point, hyperemia from the healing process may cause the fracture line to become visible due to bone resorption at the fracture margins. Some departments proceed directly to CT or MRI for suspected occult scaphoid fractures.
Each finger (digits 2–5) and the thumb (digit 1) can be imaged individually when a single digit is the clinical concern. Individual digit imaging allows for better detail and less superimposition than a full hand series.
Each finger requires three projections: PA, oblique, and lateral. The IR should be collimated to include only the affected digit plus a small margin to show joint relationships.
PA Finger: The affected finger is placed flat on the IR with the palm down. The adjacent fingers are flexed out of the way. CR enters at the proximal interphalangeal (PIP) joint of the affected finger.
Oblique Finger: The hand is rotated approximately 45 degrees externally from PA. The CR enters at the PIP joint of the affected finger.
Lateral Finger: The affected finger is placed in a true lateral position. For digits 2–5, this is typically achieved by fanning the unaffected fingers backward and bringing the affected finger into profile against the IR. CR enters at the PIP joint.
The thumb is positioned differently from the fingers because of its unique orientation (rotated 90 degrees relative to the other digits).
AP Thumb (Anteroposterior): The hand is internally rotated (pronated) so the dorsal surface of the thumb rests against the IR. The CR enters at the first MCP joint. This projection demonstrates the thumb in anatomical AP orientation.
PA Oblique Thumb: The hand is rotated approximately 45 degrees from the AP position. The CR enters at the first MCP joint.
Lateral Thumb: The hand is externally rotated so the radial side of the thumb contacts the IR. The CR enters at the first MCP joint. This view is excellent for detecting proximal phalanx fractures and first MCP dislocations (gamekeeper's thumb / skier's thumb).
Gamekeeper's thumb (skier's thumb) is an injury to the ulnar collateral ligament (UCL) of the first MCP joint. The lateral thumb projection with stress (if ordered) can demonstrate UCL rupture. On the AP view, look for a small avulsion fracture at the ulnar base of the proximal phalanx of the thumb — this is a Stener lesion equivalent when the ligament retracts and becomes interposed between the adductor pollicis aponeurosis.
Named after the Danish radiologist Otto Norgaard, this bilateral PA projection is used to evaluate early erosive changes of rheumatoid arthritis at the metacarpophalangeal (MCP) joints. Both hands are placed palms-up (supinated) on a single IR, with the thumbs extended and the fingers flexed as if catching a ball. The CR enters at the midpoint between the two hands at the level of the MCP joints. The semipronated oblique orientation profiles the radial and ulnar aspects of the MCP joints, where early rheumatoid erosions typically appear.
This specialized projection visualizes the carpal arch and the hook of hamate, pisiform, and trapezial ridge. It is indicated for suspected carpal tunnel syndrome, hook of hamate fractures, and pisiform fractures. The wrist is hyperextended (dorsiflexed) approximately 90 degrees with the palm flat on the IR. The CR is directed 15–25 degrees from the vertical toward the wrist, entering the palm at the level of the carpometacarpal joints. This view is notoriously difficult to position on patients with wrist pain — use a radiolucent support under the hand to minimize discomfort.
Even experienced technologists make positioning errors on hand and wrist exams. Here are the most frequent mistakes and how to correct them:
The hand looks asymmetrical — one side appears wider. Ensure the palm is flat against the IR with no tilt. Use a small wedge under the forearm if needed.
Fingers touching obscure bony margins. Gently separate fingers using cotton balls or radiolucent spacers between digits. Explain to the patient why this is necessary.
Extraneous anatomy increases scatter and reduces image quality. Collimate tightly to the area of interest. For individual digits, the collimation should be just larger than the digit itself.
Hands are difficult to immobilize. Use short exposure times (< 0.05 s), carefully explain breath-holding (yes, for hand exams too — any torso motion can transmit to the hand), and use a sponge to support the limb.
Insufficient ulnar deviation fails to elongate the scaphoid. Ensure the patient actively deviates the hand toward the ulnar side — the full range of motion provides the best view.
The radius and ulna are not superimposed. In a true lateral, the radial styloid should be superimposed over the ulnar styloid. Recheck elbow and wrist alignment.
Pediatric hand and wrist imaging requires special attention. Children have open growth plates (physes) that can be mistaken for fractures by the untrained eye. The distal radial and ulnar physes are common sites of Salter-Harris fractures in children.
When a patient presents with a suspected fracture, dislocation, or severe deformity, standard positioning protocols must be adapted. The following principles apply:
Try these ARRT-style multiple choice questions based on this article. Click an option to check your answer — correct answers turn green, wrong ones turn red.
Try these ARRT-style multiple choice questions based on this article. Click an option to check your answer — correct answers turn green, wrong ones turn red.