Shoulder and upper arm of child shown with deltoid muscle illustrated. Preferred site of injection is indicated by a + within a circle.

Dorsal scapular region. Quadrangular space and triangular interval.

Anterior view of the bones and muscle attachments of the axilla and pectoral region.

Transverse MRI through shoulder joint and axilla (1, greater tubercle; 2, biceps brachii; 3, glenoid labrum; 4, glenoid fossa of scapula; 5, head of humerus; 6, subscapularis; 7, infraspinatus; 8, deltoid).

Lateral view of the surface anatomy of the arm: (1) deltoid, (2) biceps brachii, (3) brachialis, (4) brachioradialis, (5) olecranon, (6) lateral epicondyle, (7) lateral head, and (8) long head.

Posterior view of the superficial muscles of the back; trapezius muscle is reflected on the left.

Transverse MRI of arm at mid humerus: BB, biceps brachii; BV, brachial vessels/nerves; MT, medial head of triceps; BC, brachialis; T, deltoid tuberosity; H, humerus; D, deltoid; LAT, lateral head triceps; LT, long head triceps; LI, lateral intermuscular s

Superficial muscles of the back.

Coronal MRI of the shoulder; A, acromion; C, clavicle; GT, greater tubercle; H, head of humerus; TR, trapezius; SP, supraspinatus; SV, suprascapular vessels/nerve; GF, glenoid fossa; S, scapula; SB, subscapularis; TM, teres minor, LB, long head of biceps

Deltoid muscle