RAD 120 — Chapter 4: Upper Extremities

Vocabulary practice flashcards covering upper extremities radiography, including osteology, joint classifications, routine positions, elbow projections, special wrist views, and positioning rules.

Hand and wrist bones

Consists of $27$ total bones: $14$ phalanges, $5$ metacarpals, and $8$ carpals.

Digits 1–5

Anatomical numbering of digits from thumb ($1\text{st}$) to pinky ($5\text{th}$).

Phalanges

Finger bones comprising proximal, middle, and distal segments for digits $2\text{--}5$, and proximal and distal segments only for the thumb.

Phalanx and metacarpal parts

The structural segments consisting of the distal head, the body (shaft), and the proximal base.

Thumb joints

The interphalangeal (IP), $1\text{st}$ metacarpophalangeal (MCP), and $1\text{st}$ carpometacarpal (CMC) joints.

Digits 2–5 joints

The distal interphalangeal (DIP), proximal interphalangeal (PIP), and metacarpophalangeal (MCP) joints.

Proximal carpal row

The carpal row consisting of the scaphoid, lunate, triquetrum, and pisiform.

Distal carpal row

The carpal row consisting of the trapezium, trapezoid, capitate, and hamate.

Carpal articulations

Articular pairings where the $1\text{st}$ MC articulates with the trapezium, $2\text{nd}$ with the trapezoid, $3\text{rd}$ with the capitate, and $4\text{th}/5\text{th}$ with the hamate.

Scaphoid

The largest proximal carpal bone; the most commonly fractured carpal bone.

Capitate

The largest carpal bone overall.

Pisiform

The smallest carpal bone; characterized by a pea-shaped appearance.

Hamate

Carpal bone distinguished by a prominent hooklike process termed the hamulus.

Radiocarpal joint

Articulation where the distal radius articulates directly with the scaphoid and lunate.

Ulnar deviation

Movement of the wrist toward the pinky side; opens the lateral carpals and elongates the scaphoid.

Radial deviation

Movement of the wrist toward the thumb side; opens the medial carpals (lunate, triquetrum, pisiform, hamate).

Upper limb joint classification

All upper limb joints are structurally and functionally classified as synovial and diarthrodial (freely movable).

Interphalangeal (IP) joints

Joints classified structurally and functionally as ginglymus (hinge).

Metacarpophalangeal (MCP) joints

Joints classified structurally and functionally as ellipsoidal (condyloid).

First carpometacarpal (1st CMC) joint

The joint between the trapezium and first metacarpal, classified as saddle (sellar).

Second to fifth carpometacarpal (2nd–5th CMC) joints

Articulations between the distal carpals and metacarpals $2\text{--}5$, classified as plane (gliding).

Intercarpal joints

Articulations between individual carpal bones, classified as plane (gliding).

Radiocarpal joint classification

Wrist articulation classified structurally and functionally as ellipsoidal (condyloid).

Proximal radioulnar joint

Articulation between the radial head and the radial notch of the ulna, classified as pivot (trochoidal).

Elbow joint

Ginglymus (hinge) joint connecting the distal humerus to the proximal radius and ulna.

Radius

The lateral forearm bone located on the thumb side.

Ulna

The medial forearm bone located on the pinky side.

Proximal radius

Anatomic segment comprising the radial head, neck, and radial tuberosity.

Distal radius

Anatomic segment comprising the styloid process and the ulnar notch.

Proximal ulna

Anatomic segment comprising the olecranon, coronoid process, coronoid tubercle, trochlear notch, and radial notch.

Distal ulna

Anatomic segment comprising the ulnar head and styloid process.

Radial notch

Depression on the proximal ulna that articulates with the radial head.

Ulnar notch

Depression on the distal radius that articulates with the ulnar head to form the distal radioulnar joint.

Trochlear notch

C-shaped depression on the proximal ulna that articulates with the trochlea of the humerus.

Olecranon process

Posterior bony projection of the proximal ulna that forms the point of the elbow.

Coronoid process

Anterior projection of the proximal ulna.

Coronoid tubercle

Small prominence located on the medial aspect of the coronoid process.

Distal humerus

Anatomic region consisting of the capitulum, trochlea, and medial and lateral epicondyles.

Capitulum

Lateral condyle of the distal humerus that articulates with the radial head.

Trochlea

Medial condyle of the distal humerus that articulates with the ulna.

Radial fossa

Depression on the anterior distal humerus situated directly above the capitulum.

Coronoid fossa

Depression on the anterior distal humerus situated directly above the trochlea.

Olecranon fossa

Deep posterior depression on the distal humerus that receives the olecranon process.

Elbow flexion

Movement in which the coronoid process enters the coronoid fossa of the humerus.

Elbow extension

Movement in which the olecranon process enters the olecranon fossa of the humerus.

Forearm pronation

Forearm rotation that causes the radius to cross over the ulna.

Forearm supination

Forearm position in which the radius and ulna lie approximately parallel to each other.

PA projection of fingers

Positioned with fingers extended and separated; central ray is directed to the PIP joint.

PA oblique projection of fingers

Positioned with $45^\circ$ rotation; central ray is directed to the PIP joint.

Lateral projection of fingers

Positioned in true lateral; central ray is directed to the PIP joint.

AP projection of thumb

Positioned with the posterior aspect of the thumb against the IR; central ray is directed to the $1\text{st}$ MCP joint.

PA oblique projection of thumb

Positioned in a $45^\circ$ medial oblique; central ray is directed to the $1\text{st}$ MCP joint.

Lateral projection of thumb

Positioned in true lateral; central ray is directed to the $1\text{st}$ MCP joint.

PA projection of hand

Positioned palm down; central ray is directed perpendicular to the $3\text{rd}$ MCP joint.

PA oblique projection of hand

Positioned with $45^\circ$ lateral rotation; central ray is directed to the $3\text{rd}$ MCP joint.

Fan lateral projection of hand

Positioned with digits separated and parallel to the IR; central ray is directed to the $2\text{nd}$ MCP joint.

Lateral hand in flexion or extension

Positioned with metacarpals superimposed; central ray is directed to the $2\text{nd}\text{--}5\text{th}$ MCP joints.

PA projection of wrist

Positioned palm down; central ray is directed to the midcarpal area.

PA oblique projection of wrist

Positioned with $45^\circ$ lateral rotation; central ray is directed to the midcarpal area.

Lateral projection of wrist

Positioned in true lateral with radius and ulna superimposed; central ray is directed to the midcarpal area.

AP projection of forearm

Positioned supinated, including both wrist and elbow joints; central ray is directed to the midforearm.

Lateral projection of forearm

Positioned with the elbow flexed $90^\circ$ and thumb up, including both joints; central ray is directed to the midforearm.

AP projection of elbow

Positioned fully extended and supinated; central ray is directed to the midelbow.

Lateral projection of elbow

Positioned flexed $90^\circ$ with thumb up; central ray is directed to the midelbow.

AP oblique projection of elbow

Positioned with $45^\circ$ medial or lateral rotation; central ray is directed to the midelbow.

AP elbow demonstrated anatomy

Demonstrates the distal humerus, proximal radius, and proximal ulna, with the radial head partially superimposed by the ulna.

AP lateral (external) oblique elbow

Projection demonstrating the radial head, neck, and tuberosity FREE of the ulna, with the capitulum and lateral epicondyle in profile.

AP medial (internal) oblique elbow

Projection demonstrating the coronoid process in profile, as well as the trochlea and medial epicondyle.

Lateral elbow demonstrated anatomy

Demonstrates the olecranon and trochlear notch in profile, fat pads, and three concentric arcs.

True lateral elbow criteria

Epicondyles superimposed, three concentric arcs visualized, and elbow flexed $90^\circ$.

Three concentric arcs

Radiographic landmarks of a lateral elbow formed by the trochlear sulcus, outer ridges of the capitulum and trochlea, and the trochlear notch.

AP elbow partial flexion

Routine consisting of two separate images when full extension is not possible: humerus parallel to IR and forearm parallel to IR.

AP elbow partial flexion (humerus parallel)

Partial flexion position that best demonstrates the distal humerus.

AP elbow partial flexion (forearm parallel)

Partial flexion position that best demonstrates the proximal radius and ulna.

Coyle method — radial head

Positioned with $90^\circ$ elbow flexion and central ray angled $45^\circ$ toward the shoulder; demonstrates radial head, neck, and tuberosity.

Coyle method — coronoid

Positioned with $80^\circ$ elbow flexion and central ray angled $45^\circ$ away from the shoulder; demonstrates coronoid process in profile.

AP acute flexion (Jones method)

Projection used when the elbow cannot extend; demonstrates the olecranon process.

Anterior elbow fat pad

Soft tissue structure normally faintly visible; elevation may indicate joint effusion.

Posterior elbow fat pad

Soft tissue structure normally not visible; visualization following trauma suggests joint effusion.

Supinator fat stripe

Fat stripe located anterior to the proximal radius; displacement may indicate a radial head or neck fracture.

PA scaphoid with ulnar deviation

Special wrist projection that elongates the scaphoid; central ray is angled $10\text{--}15^\circ$ proximally.

Modified Stecher method

Scaphoid projection with hand elevated $20^\circ$, often accompanied by ulnar deviation; central ray is perpendicular.

Scaphoid central ray location

Directing the central ray $\frac{3}{4}\text{ inch}$ distal and medial to the radial styloid.

PA projection with radial deviation

Special wrist projection that opens ulnar-side carpal spaces; central ray is directed to the midcarpal area.

Gaynor-Hart method

Tangential projection demonstrating the carpal canal (carpal tunnel) with the wrist hyperextended.

Gaynor-Hart central ray

Central ray angled $25\text{--}30^\circ$ proximally to the long axis of the hand.

Gaynor-Hart evaluation criteria

Radiographic outcome demonstrating the pisiform and the hamulus separated in profile.

Bilateral PA clenched wrist

Special view assessing scapholunate ligament injury, evaluated by widening of the scapholunate space.

Modified Robert method

Special projection demonstrating a Bennett fracture at the base of the $1\text{st}$ metacarpal.

Brewerton method

Special MCP joint projection utilized to evaluate early rheumatoid arthritis.

Upper limb SID

Maintained at a minimum distance of $40\text{ inches}$.

Upper limb exposure factors

Technical factors utilizing low-to-medium kVp, short exposure time, small focal spot, and adequate mAs.

Upper limb grids

Generally nongrid imaging unless the anatomic part thickness exceeds $4\text{ inches}$.

General central ray (CR) rule

Directed perpendicular to the part and image receptor unless otherwise indicated.

Upper limb IR alignment

Positioned such that the long axis of the anatomy is parallel to the long axis of the IR.

Upper limb collimation

Four-sided collimation including all necessary anatomy and soft tissue margins.

Correct exposure appearance

Demonstrated radiographically by clear soft tissue margins and sharp bony trabecular markings.

Laterality labeling

Identifying RIGHT or LEFT when applicable and confirming marker correctness prior to labeling.