Triceps brachii

Triceps Brachii

The Triceps Brachii (pronounced: TRY-seps BRAY-key-eye) is a large, three-headed muscle located at the back of the upper arm. The term "triceps" is derived from the Latin words "tri" (meaning three) and "ceps" (meaning head), referring to the muscle's three distinct heads: the long head, the lateral head, and the medial head.

Etymology

The term "Triceps Brachii" is derived from Latin. "Triceps" means "three-headed" and "Brachii" refers to its location in the arm. The muscle is named for its three points of origin, or 'heads', and its location in the upper arm.

Anatomy

The Long Head of the Triceps Brachii originates from the scapula, specifically the infraglenoid tubercle. It extends down the arm, along the back, and inserts into the olecranon process of the ulna.

The Lateral Head originates from the posterior surface of the humerus, above the radial groove. It also inserts into the olecranon process of the ulna.

The Medial Head originates from the posterior surface of the humerus, below the radial groove. Like the other two heads, it inserts into the olecranon process of the ulna.

Function

The primary function of the Triceps Brachii is to facilitate the extension of the elbow joint. It also assists in the adduction and extension of the shoulder joint.

Related Terms

Elbow Joint - The joint where the Triceps Brachii inserts and performs its primary function.
Humerus - The bone from which the lateral and medial heads of the Triceps Brachii originate.
Scapula - The bone from which the long head of the Triceps Brachii originates.
Ulna - The bone into which all three heads of the Triceps Brachii insert.