MRCP UK EXAMINATIONS

Detailed explanation-1: -With the arm adducted, the triceps muscle acts to hold the head of the humerus in the glenoid cavity. This action helps prevent any displacement of the humerus. The long head also assists with the extension and adduction of the arm at the shoulder joint.

Detailed explanation-2: -The triceps Brachii (TB) is a powerful extensor muscle of the upper extremity. 1 It has been described as a single muscle unit with three heads (medial, lateral, and long heads), 2 and a cadaver study found that the medial head of the TB was attached to the olecranon by a deeper separated tendon than the other heads.

Detailed explanation-3: -Actions of the Triceps Brachii Muscle Long Head: a. Extends the forearm at elbow. (It also extends the arm at the shoulder).

Detailed explanation-4: -All the heads of the triceps brachii can assist in extension of elbow. However, because the long head crosses the shoulder joint; the long head can also assist in adduction and extension of the arm at the shoulder joint.