AP Shoulder

AP Shoulder Position Diagram

Reference AP Shoulder Radiograph

Exposure Factors

65-70

Kilovoltage (kV)

15-20

Milliamperage (mAs)

Fine Focus

Focus Type

105-115 cm

Source-Image Distance

With Bucky

Configuration

Medium-low exposure: Parameters for optimal visualization of shoulder joint

Anatomical Structures Visible

Should be clearly observed:

Shoulder joint (glenohumeral)
Complete clavicle
Proximal humerus (head and neck)
Part of scapula (acromion, scapular spine)
Glenohumeral joint space

Field verification:

PROXIMAL HUMERUS

Head and neck visible

COMPLETE CLAVICLE

From sternum to acromion

Proper field: Include proximal humerus and complete clavicle in same image

Cassette Size and Orientation

24 × 30 cm

Transverse

Standard

Transverse orientation to cover shoulder joint and adjacent structures

Patient Positioning

Patient in standing or supine position

Place shoulder joint in center of bucky

Rotate body toward affected shoulder side, shoulder in contact with bucky

Top of cassette 5 cm above shoulder

Extend affected extremity with hand at side, palm against thigh

Imaginary line between epicondyles at 45° over cassette plane

Central Ray Point

Coracoid process

Direction: Horizontal and perpendicular to shoulder joint

Location: At level of coracoid process of scapula, centered on cassette

Objective: Optimal glenohumeral joint visualization

Specific Hand Position

Correct Position

Hand at side of body

Palm of hand against thigh

Arm in neutral rotation

Epicondylar Alignment

Line between epicondyles at 45° over cassette plane

Avoids structure superposition

Improves joint visualization

Patient Instructions

"Do not breathe during the exposure"

Maintain position without movement and apnea during radiographic exposure

1. "Turn your body slightly toward the affected side"
2. "Keep your hand resting against your thigh"
3. "Stay completely still"
4. "Take a deep breath and hold it"
5. "Do not move during the exposure"

Optimal Image Characteristics

Joint Space

Glenohumeral clearly visible

No Superposition

Differentiated bone structures

Alignment

Humeral head centered in glenoid

Full Field

Proximal humerus to clavicle

Common Technical Challenges

Frequent problems in AP shoulder projection:

Structure superposition from incorrect arm rotation
Insufficient body rotation not placing shoulder flat against bucky
Incorrect hand position affecting humeral rotation
Exclusion of structures from poor cassette placement
Patient movement during exposure

Solution: Verify adequate body rotation and hand position with palm against thigh

Special Considerations

Painful Patient

Position with maximum possible comfort, adjust rotation according to tolerance.

Geriatric Patient

Consider mobility limitations, possible need for additional support.

Pediatric Patient

Reduce exposure according to age and ALARA protocol, adjust cassette size.

Clinical Indications

Proximal humerus fractures

Glenohumeral dislocations

Osteoarthritis and arthritis

Pain and joint limitation