1.5 Intrinsic Muscle of the Thoracic Limb: Caudal Muscles of the Arm

Caudal Muscles of the Arm

Tensor fasciae antebrachii

Triceps brachii

Anconeus

name the caudal muscles of the arm (3)

Tensor fasciae antebrachii

• thin, strap muscle that extends from the latissimus dorsi to the medial fascia of the antebrachium and olecranon.

• It lies on the long head of the triceps brachii muscle.

• Origin: fascia covering the lateral side of the latissimus dorsi

• Insertion: olecranon

• Action: to extend the elbow joint

• Innervation: Radial nerve

Triceps brachii

• large, powerful muscle composed of four head: long head (caudal border of the scapula), lateral head (tricipital line of the humerus), medial head (crest of the lesser tubercle), accessory head (neck of the humerus)

• its long head crosses the shoulder, and all heads cross the elbow joint to insert on the olecranon.

• Origin: Caudal border of the scapula

• Insertion: olecranon tuber

• Action: It extends the elbow and flexes the shoulder (long head of triceps)

• Innervation: Radial nerve

Anconeus

• small muscle that arises from the distal part of the humerus to insert on the lateral part of the olecranon

• Origin: lateral supracondylar crest

• Insertion: proximal end of the ulna

• Action: to extend the elbow joint

• Innervation: Radial nerve

True

TRUE OR FALSE: long head, medial head, and accessory head of the triceps brachii is seen in the medial view