1 — Triceps brachii, medial head; deep head; 2 — Triceps brachii, lateral head; 3 — Humerus; 4 — Lateral intermuscular septum of arm; 5 — Lateral bicipital groove; 6 — Radial nerve; 7 — Brachialis; 8 — Cephalic vein; 9 — Biceps brachii; 10 — Brachial fascia; 11 — The integument; 12 — Medial bicipital groove; 13 — Brachial artery; 14 — Basilic vein; 15 — Median nerve; 16 — Brachial veins; 17 — Ulnar nerve; 18 — Medial intermuscular septum of arm; 19 — Triceps brachii, long head