A patient has a deep cut wound on the posterior surface of his shoulder in its middle third. What muscle might be injured?

Answer options

1. Anconeus muscle
2. Biceps muscle of arm
3. Triceps muscle of arm
4. Coracobrachial muscle
5. Brachial muscle

Explanation

The triceps, also triceps brachii is a large muscle on the back (posterior) of the upper arm between the shoulder and the elbow. It is the muscle principally responsible for the extension of the elbow joint (straightening of the arm).