Triceps

Definition

The triceps brachii, commonly referred to as the triceps, is a large muscle on the posterior (back) side of the upper arm. It is the main extensor muscle of the elbow joint, responsible for extending the forearm and straightening the arm.

5 Must Know Facts For Your Next Test

1. The triceps brachii has three heads: the long head, the lateral head, and the medial head.
2. The long head of the triceps originates on the infraglenoid tubercle of the scapula, while the lateral and medial heads originate on the posterior surface of the humerus.
3. The triceps is the primary muscle responsible for extending the forearm and straightening the arm, which is essential for many upper body movements and activities.
4. The triceps also plays a role in stabilizing the shoulder joint and assisting with other movements of the arm, such as adduction and horizontal abduction.
5. Injuries or weakness in the triceps can lead to difficulty with tasks requiring elbow extension, such as pushing, pressing, or straightening the arm.

Review Questions

• Describe the anatomical location and function of the triceps brachii muscle.
  • The triceps brachii is a large muscle located on the posterior (back) side of the upper arm. It is the main extensor muscle of the elbow joint, responsible for extending the forearm and straightening the arm. The triceps has three distinct heads: the long head, the lateral head, and the medial head, each originating from different areas of the humerus and scapula. The triceps plays a crucial role in many upper body movements and activities that require elbow extension, such as pushing, pressing, or straightening the arm.
• Explain the role of the triceps brachii in stabilizing the shoulder joint and assisting with other arm movements.
  • In addition to its primary function of extending the elbow, the triceps brachii also plays a role in stabilizing the shoulder joint and assisting with other movements of the arm. The long head of the triceps, which originates on the scapula, helps to stabilize the shoulder joint during arm movements. The triceps also contributes to adduction and horizontal abduction of the arm, providing additional support and control during these movements. This multifaceted role of the triceps brachii highlights its importance in overall upper body function and stability.
• Analyze the potential impact of an injury or weakness in the triceps brachii muscle and how it might affect an individual's daily activities and upper body performance.
  • An injury or weakness in the triceps brachii muscle can have significant consequences for an individual's daily activities and upper body performance. Since the triceps is the primary extensor of the elbow joint, any impairment in its function can lead to difficulties with tasks requiring elbow extension, such as pushing, pressing, or straightening the arm. This can impact a wide range of activities, from pushing open a door to performing push-ups or other upper body exercises. Additionally, the triceps' role in stabilizing the shoulder joint and assisting with other arm movements means that a weakness in this muscle can also affect the individual's overall upper body strength, coordination, and range of motion. Proper rehabilitation and strengthening of the triceps brachii is essential for restoring full upper body function and performance.

Related terms

Brachialis:

A muscle located deep to the biceps brachii, responsible for flexing the elbow joint.

Brachioradialis:

A muscle located on the lateral (outer) side of the forearm, assisting in flexing the elbow joint.

Deltoid: A large, triangular muscle that covers the shoulder joint, responsible for abducting, flexing, and extending the arm.