Muscles of the posterior compartment of the arm

Question 1

Triceps brachii

Answer 1

Origin:

• Long head - infraglenoid tubercle of scapula;
• Medial head - posterior surface of humerus;
• Lateral head - posterior surface of humerus

Insertion:

• Olecreanon

Innervation:

• Radial nerve (C6, C7, C8)

Function:

• Extension of the forearm at the elbow joint; long head can also extend and adduct the arm at the shoulder joint