108 Hand, Forearm, Humerus A&P

What should be done with a patient's sling or splints before imaging?

Do not remove them without permission from the provider.

What is the recommended Source-to-Image Distance (SID) for forearm and elbow imaging?

40 inches.

What is the positioning requirement for the patient's wrist, elbow, and humerus during imaging?

They should be on the same plane.

What is the central ray (CR) entry point for an AP forearm projection?

At the midpoint of the forearm.

What structures should be included in an AP forearm projection?

Entire forearm, including wrist, distal humerus, and proximal row of carpal bones.

What is the patient position for a lateral forearm projection?

Elbow centered to the middle of the IR with humeral epicondyles parallel to the IR.

What should be the CR orientation for a lateral forearm projection?

Mid forearm

What is the evaluation criteria for an AP elbow projection?

Radial head, neck, and tuberosity slightly superimposed over the proximal ulna and the elbow joint open.

What is the purpose of the partial flexion position for an AP elbow?

To image the distal humerus and proximal forearm separately when the patient cannot fully extend the elbow.

What is the CR orientation for the AP elbow in the partial flexion position?

Perpendicular to the humerus, passing through the elbow joint.

What structures are shown in the AP elbow—distal humerus partial flexion position?

Distal humerus without rotation, proximal radius superimposed over the ulna, and a closed elbow joint.

What is the CR angle for the axiolateral (Coyle) projection for the radial head?

Angled 45 degrees toward the shoulder.

What is the positioning for the AP humerus projection?

Epicondyles perpendicular to the IR with the top border of the IR approximately 1½ inches above the humeral head.

What structures should be visible in a lateral humerus projection?

Both elbow and shoulder joints, with superimposed humeral epicondyles.

What is the CR orientation for the transthoracic lateral projection of the humerus?

Perpendicular to the midportion of the humerus, entering at the surgical neck.

What is the respiration instruction for the transthoracic lateral projection?

Exposure made on inspiration or using a breathing technique with slow, deep breathing.

What is the evaluation criteria for the trauma horizontal beam lateral projection?

Both proximal and distal humerus joints should be included.

Fossa

Shallow depression in a bone

Styloid

Pointed projection

Condyle

Rounded articular surface

Epicondyle

Prominence above a condyle

Tubercle, Tuberosity

Roughened bump for muscle attachment

Head

Rounded proximal end of a bone

radiocarpal joint

Wrist joint formed by articulation between the distal radius and the proximal row of carpal bones

intercarpals

the space between the carpals

distal radioulnar joint

The articulation between the distal ends of the radius and ulna that allows for pronation and supination of the forearm

MCP

Metacarpophalangeal

DIP

Distal interphalngeal

PIP

Proximal interphalangeal

Humerus, elbow, forearm positioning

Must be in same plane. Long bones: include both joints. Always do AP & Lateral.

SID

40 inches.

Collimation

Collimate ~1 inch beyond skin line.

Grid usage

Used for proximal humerus/transthoracic.

Forearm - AP Positioning

Patient seated, arm extended, palm up, epicondyles parallel to IR. CR → mid-forearm. Shows entire radius & ulna, wrist + elbow joints.

Forearm - Lateral Positioning

Elbow flexed 90°, thumb up, wrist & elbow same plane. CR → mid-forearm. Shows radius/ulna superimposed distally, elbow flexed.

Elbow - AP Positioning

Arm extended, palm up, epicondyles parallel to IR. CR → mid-elbow. Shows distal humerus, proximal radius & ulna.

Elbow - AP Partial Flexion

Used if elbow cannot fully extend. CR perpendicular to elbow joint, angled through humerus or forearm.

Elbow - Lateral Positioning

Elbow flexed 90°, thumb up. CR → mid-elbow. Shows olecranon, fat pads, superimposed epicondyles.

Elbow - AP Medial Oblique

Hand pronated, elbow extended. CR → mid-elbow. Shows coronoid process free of superimposition.

Elbow - AP Lateral Oblique

Hand supinated, elbow externally rotated. CR → mid-elbow. Shows radial head & neck free of superimposition.

Elbow - Coyle Method

Elbow flexed 90°, CR angled 45° toward shoulder. Shows radial head & capitulum.

Humerus - AP Positioning

Arm extended, palm up, epicondyles parallel to IR. CR → mid-humerus. Shows entire humerus, shoulder + elbow joints.

Humerus - Lateral Positioning

Elbow flexed 90°, palm on hip or abdomen. Epicondyles perpendicular to IR. CR → mid-humerus. Shows lateral humerus, superimposed epicondyles.

Humerus - Transthoracic (fractures)

Affected arm against IR, unaffected arm raised. CR → surgical neck. Breathing technique or full inspiration. Shows lateral humerus through thorax.

Forearm Bones

Ulna = medial (pinky side). Radius = lateral (thumb side).

Radius - Proximal Structures

Head, neck, radial tuberosity.

Radius - Distal Structures

Base with styloid process, ulnar notch.

Ulna - Proximal Structures

Olecranon process, coronoid process, trochlear notch, radial notch.

Ulna - Distal Structures

Head, styloid process.

Humerus - Proximal Structures

Head (articulates with scapula), anatomic neck, surgical neck (fracture site), greater tubercle, lesser tubercle.

Humerus - Distal Structures

Medial/lateral epicondyles, trochlea (ulna), capitulum (radius), coronoid fossa (anterior), radial fossa (anterior), olecranon fossa (posterior).

Elbow Joint - Components

Humeroulnar, humeroradial, proximal radioulnar joints, all within one capsule.

Elbow Joint - Movements

Flexion/extension (hinge) and supination/pronation (pivot).

Fat Pads of the Elbow

Anterior fat pad, posterior fat pad (hidden unless pathology), fat pad sign = displaced triangular shadows → occult radial head fracture.

Bony Surface Landmarks

Fossa = depression. Styloid = pointed projection. Condyle = rounded articular surface. Epicondyle = process above condyle. Tubercle/tuberosity = roughened bump. Head = rounded proximal end of bone.

AP forearm part position

Elbow extended with hand supinated ; humeral epicondyles parallel to IR

AP forearm CR placement

midpoint of forearm

Lateral forearm part position

Elbow is flexed 90 degrees, thumb side up ; ulnar and radial styloid processes superimposed (stacked)

forearm, elbow, and humerus patient positioning

wrist, elbow, and humerus on the same plane. Patient is seated with legs not under table

Lateral forearm central ray

midpoint of forearm

AP elbow part positioning

elbow extended and hand supinated, elbow centered to middle of IR

AP elbow central ray centering

perpendicular to elbow joint

Lateral elbow part positioning

Elbow flexed 90 degrees, thumb side up, humeral epicondyles perpendicular to IR

Lateral elbow CR centering

perpendicular to elbow joint

AP elbow partial flexion (distal humerus) part positioning

Supinate hand and center IR to condyles of humerus with elevated forearm

AP elbow partial flexion (distal humerus) CR centering

Perpendicular to elbow joint, passing through elbow joint

AP elbow partial flexion (proximal forearm) part positioning

Leave elbow flexed, patient is standing, supinate hand and center IR to condyles of humerus

AP elbow partial flexion (proximal forearm) CR centering

Perpendicular to elbow joint and long axis of forearm

Elbow AP medial oblique part positioning

Elbow centered to IR, rotate the arm 45 degrees medially

Elbow AP medial oblique CR centering

perpendicular to elbow joint, collimatation is 3 inches above and below elbow crease

Elbow AP lateral oblique part positioning

Laterally rotate arm 45 degrees, first and second digit will touch table

Elbow AP lateral oblique CR centering

Perpendicular to elbow joint, collimation 3 inches above and below elbow joint

When to use the coyle method for radial head

When patients cannot fully extend the elbow for medial and lateral oblique projections

Axiolateral (Coyle method) positioning

the CR is at a cephalic angle of 45 degrees towards shoulder, the patients hand is pronated with the elbow flexed at a 90 degree angle

Axiolateral (Coyle method) CR centering

entering elbow joint at mid elbow

AP humerus part positioning

Patient is standing with back to board, arm out with supinated hand

AP humerus CR centering

Perpendicular to midportion of humerus, collimated to include the elbow joint and 1 ½ inches above humeral head with 1 inch on the sides

Lateral humerus part positioning

Patients body facing board, top of IR 1 ½ inches above humeral head, elbow flexed with hand over stomach, shoulder and elbow touching board

Lateral humerus CR centering

at midpoint of humerus

Transthoracic lateral part positoining

Patients left side is toward the board, with non injured arm raised with hand on back of head

Transthoracic lateral CR centering

Centered at surgical neck of humerus to IR

Structures shown in Lateral Forearm

Entire forearm with wrist and distal humerus

Structures shown in AP elbow

Medial and lateral epicondyle, Trochlea, proximal ulna, capitulum, radial head, radial neck, radial tuberosity

Structures shown in Lateral elbow

Humeral epicondyles, radial head, coronoid process, Olecranon process

Structures shown in AP medial oblique elbow

Coronoid, coronoid process, ulna, radial head, radial neck, olecranon process, olecranon fossa

Structures shown in AP lateral oblique elbow

Radial head, Radial neck, Tuberosity, ulna, capitulum

Structures shown in Axiolateral (Coyle) radial head

Open joint space between radial head and capitulum, humeral epicondyles

Structures shown in AP Humerus

Elbow and shoulder joints, Humeral epicondyles, Humeral head, greater tubercle

Structures shown in Lateral Humerus

Elbow and shoulder joints, superimposed humeral epicondyles, Lesser tubercle, Greater tubercle superimposed over humeral head

Structures shown in Transthoracic Lateral

Unaffected humerus above shoulder, proximal half of humerus projected through thorax

Where is the radial tuberosity?

On the radius, below the radial head

What is the number one thing to remember when doing forearm, elbow, and humerus

Always keep each of them on the same plane

technique for wrist

55 kvp at 1.5 to 2 MA

KvP for forearm

60-65

Technique for humerus

65-70 kvp at 2.5 - 3 MAs

Instruction for upper extremities

Don’t breathe, don’t move

technique for transthoracic lateral

80 kvp at 40 ma

How can you tell if it is a AP humerus just by looking at the humerus

The greater tubercle is shown on the lateral side of the humerus

Breathing technique

Have the patient breathe normally

Condyle over the ulna

Trochlea