Which muscles are the prime movers for elbow extension?

Which muscles are the prime movers for elbow extension?

• A. Brachialis and Biceps brachii
• B. Triceps brachii and Anconeus
• C. Anconeus and Brachioradialis
• D. Deltoid

Answer: (B)

Elbow extension is produced primarily by the triceps brachii, which straightens the forearm at the elbow. The anconeus assists this motion and helps stabilize the joint, especially when resistance is applied. The other muscles shown don’t extend the elbow: the brachialis and biceps brachii flex the elbow; the brachioradialis mainly flexes the elbow in a neutral forearm position; and the deltoid acts on the shoulder, not the elbow. So the primary movers for elbow extension are the triceps brachii and the anconeus.

Elbow extension is produced primarily by the triceps brachii, which straightens the forearm at the elbow. The anconeus assists this motion and helps stabilize the joint, especially when resistance is applied. The other muscles shown don’t extend the elbow: the brachialis and biceps brachii flex the elbow; the brachioradialis mainly flexes the elbow in a neutral forearm position; and the deltoid acts on the shoulder, not the elbow. So the primary movers for elbow extension are the triceps brachii and the anconeus.