Educational resource developed at the Veterinary Anatomy Section, ICAR-Indian Veterinary Research Institute (ICAR-IVRI), Bareilly.
📝 STANDARD DESCRIPTION:
Type: Intrinsic, Brachial
Origin: Proximal caudal aspect of humerus
Insertion: Medial aspect of proximal radius and medial coronoid process of ulna
Function: Pure and powerful flexor of the elbow joint.
📚 DETAILED DESCRIPTION:
THE ELBOW FLEXOR PURIST
Located within the musculospiral groove of the humerus, deep to the biceps and adjacent to the radial nerve.
COURSE MECHANICS: Originates from the proximal caudal humerus, wraps around the medial aspect, and passes deep to the biceps tendon near the elbow to insert on the proximal radius and ulna.
PURE FLEXOR: Unlike the biarticular biceps, the brachialis acts only on the elbow joint, making it the 'pure' elbow flexor. It provides the actual power for rapid flexion during the swing phase of locomotion.
NEURAL SUPPLY: Primarily musculocutaneous nerve, but receives branches from the radial nerve in cattle (dual innervation pattern in some specimens).
SURGICAL CORRIDOR: Directly deep to the biceps; must be retracted to access the elbow joint capsule medially.
// COMPARATIVE ANALYSIS
| DOG |
Exclusively musculocutaneous innervation; no radial contribution. |
| HORSE |
Similar position; less bulky than biceps. |
CLINICAL RELEVANCE
Radial Nerve Compression: Located adjacent to radial nerve in musculospiral groove; hematomas here affect both structures.
