RAD 210 Ch. 4 Upper Limb Flashcards
What are the four main groups of bones in the upper limb?
- Hand and wrist
- Forearm
- Arm (humerus)
- Shoulder girdle
How many bones are in the hand and wrist?
27 bones total
- 14 phalanges (fingers & thumb)
- 5 metacarpals (palm)
- 8 carpals (wrist)
When is a grid used in upper limb imaging?
Only when the body part measures larger than 10 cm (e.g., shoulder).
What patient positioning is required for a PA Oblique Finger projection?
- Seated, elbow flexed 90°, hand and forearm resting on table.
- Rotate hand 45° medially or laterally, depending on digit examined.
- Fingers separated and parallel to IR.
What anatomy should be demonstrated in a PA Finger projection?
- Distal phalanx to distal metacarpal, including joints.
- No rotation, with symmetric appearance of shafts.
- Equal soft tissue on both sides of the phalanges.
What anatomy should be demonstrated in a PA Oblique Finger projection?
- Oblique view of distal, middle, and proximal phalanges.
- Distal metacarpal and associated joints included.
What is the correct patient position for a PA Finger projection?
- Seated, elbow flexed 90°, hand and forearm on table.
- Hand pronated, fingers separated.
What positioning confirms a correct PA Oblique Finger projection?
- Interphalangeal and MCP joints open.
- Finger is 45° oblique with no superimposition of adjacent digits.
Which two carpal bones should be clearly visible for PA Oblique Wrist?
Trapezium & scaphoid
Q: What is the standard SID for upper limb radiography?
40 inches (100 cm)
What anatomy should be demonstrated in a Lateral Finger projection?
- Distal phalanx to distal metacarpal with clear joint spaces.
- No superimposition of adjacent digits.
What anatomy should be demonstrated in an AP Thumb projection?
Distal and proximal phalanges, first metacarpal, trapezium, and joints
What positioning confirms a correct Lateral Thumb projection?
- Thumb in true lateral position.
- Interphalangeal and MCP joints open.
- CR and collimation centered at the first MCP joint.
What is the Modified Roberts Method (AP Axial Thumb projection) used for?
Better visualization of the first carpometacarpal (CMC) joint.
What is the CR angulation for an AP Axial (Modified Roberts Method) Thumb projection?
CR angled 10°–15° proximally (toward the wrist), centered at first CMC joint.
What anatomical alignment indicates a true lateral for Lateral Wrist Projection?
Ulnar head superimposed over the distal radius
Why is ulnar deviation used for PA Axial (Ulnar Deviation) Scaphoid Projection?
- Reduces foreshortening of the scaphoid
- Opens carpal joint spaces
What is this method “AP Axial Projection: Hand (Brewerton Method)” primarily used for?
Early detection of rheumatoid arthritis
What anatomy should be visible for “AP Elbow (Partially Flexed)”?
- Distal ⅓ of humerus (best seen on “humerus parallel” projection)
- Proximal ⅓ of forearm (best seen on “forearm parallel” projection)
For “AP Oblique Elbow (Medial vs. Lateral Oblique)” what does each projection best visualize?
- Medial (internal) oblique: Coronoid process
- Lateral (external) oblique: Radial head & neck
For “AP Oblique Elbow (Exposure Factors)”
What must be clearly demonstrated?
- Optimal density & contrast
- No motion
- Sharp bony trabeculation & soft tissue detail
How many phalanges does each finger and thumb have?
- Fingers (Digits 2-5): 3 phalanges (proximal, middle, distal)
- Thumb (1st Digit): 2 phalanges (proximal, distal)
What are the three parts of a phalanx (finger bone)?
- Head (distal, rounded end)
- Body (shaft, curved middle section)
- Base (proximal, expanded end)
How many carpal bones are in the wrist?
8 carpal bones that are divided into proximal & distal rows (4 in each)
What are the four bones in the Proximal Row (lateral to medial)?
- Scaphoid (boat-shaped, most commonly fractured)
- Lunate (moon-shaped, articulates with capitate)
- Triquetrum (pyramidal, three articular surfaces)
- Pisiform (pea-shaped, smallest carpal bone)
What are the four bones in the Distal Row (lateral to medial)?
- Trapezium (four-sided, articulates with thumb)
- Trapezoid (smallest distal carpal, wedge-shaped)
- Capitate (largest carpal, has a rounded head)
- Hamate (hook-shaped, has the hamulus process)
Which carpal bone is the most commonly fractured?
Scaphoid (articulates with the radius, important in wrist movement)
Which carpal has a “hook-like” process?
Hamate (has the hamulus process)
What is the Carpal Sulcus (Carpal Tunnel)?
- A concave groove formed by the palmar surface of the carpals
- Allows passage of major nerves & tendons
What are the names of the epicondyles of the humerus?
- Lateral Epicondyle (smaller, above capitulum)
- Medial Epicondyle (larger, above trochlea)
What is the mnemonic for Remembering the Carpals (Proximal to Distal, Lateral to Medial)?
“Some Lovers Try Positions That They Can’t Handle”
(Scaphoid, Lunate, Triquetrum, Pisiform, Trapezium, Trapezoid, Capitate, Hamate)
What are the two bones of the forearm?
- Radius (lateral/thumb side)
- Ulna (medial/pinky side)
What are the two radioulnar joints, and what is their function?
*Proximal & Distal Radioulnar Joints
*Allow rotational movement of the forearm (pronation & supination)
What are the two processes of the proximal ulna?
- Olecranon Process (posterior, forms elbow tip)
- Coronoid Process (anterior, fits into coronoid fossa of humerus)
What is the trochlear notch?
- A large, concave depression in the ulna
- Articulates with trochlea of humerus
What are the three concentric arcs visible on a true lateral elbow radiograph?
- Trochlear Sulcus (smallest arc)
- Capitulum & Trochlea outer ridges
- Trochlear Notch of Ulna (largest arc)
What type of synovial joint are the interphalangeal (IP) joints?
- Hinge (Ginglymus) joints
- Allow only flexion and extension
What type of synovial joint are the metacarpophalangeal (MCP) joints?
- Ellipsoidal (Condyloid) joints
- Allow flexion, extension, abduction, adduction, and circumduction
What type of synovial joint is the 1st carpometacarpal (CMC) joint (thumb)?
- Saddle (Sellar) joint
- Allows opposition, flexion, extension, abduction, adduction, and rotation
What are the three concentric arcs in a true lateral elbow?
- Trochlear Sulcus (smallest arc)
- Capitulum & Trochlea (double-lined intermediate arc)
- Trochlear Notch (largest arc)
What type of joint is the elbow?
- Ginglymus (Hinge) Joint
- Allows flexion & extension
What is the trochlear notch?
- A large, concave depression in the ulna
- Articulates with trochlea of humerus
What is the radial notch?
- A shallow depression on the lateral ulna * Articulates with the head of the radius
Which bone rotates during pronation?
Radius rotates around the stationary ulna
What is the mnemonic to remember the capitulum?
Capitulum = “Cap” = Head of the Radius
What are the two epicondyles of the distal humerus?
- Lateral Epicondyle (smaller, near capitulum)
- Medial Epicondyle (larger, more prominent)
What is the deep posterior depression on the distal humerus?
Olecranon Fossa (receives olecranon process when arm extends)
Why is an accurate lateral elbow position important?
- Helps visualize fat pads (important for trauma diagnosis)
- Ensures joint alignment is correct
What movement occurs at the metacarpophalangeal (MCP) joints?
- Ellipsoidal (Condyloid) Joint
- Allows flexion, extension, abduction, adduction, circumduction
What is the trochlear sulcus, and why is it important?
- It is the depression on the trochlea (seen in lateral view of elbow)
- Helps evaluate joint alignment in elbow radiographs
