Educational resource developed at the Veterinary Anatomy Section, ICAR-Indian Veterinary Research Institute (ICAR-IVRI), Bareilly.
📝 STANDARD DESCRIPTION:
Type: Intrinsic, Scapulohumeral (Medial)
Origin: Caudal angle and caudal border of scapula
Insertion: Teres major tuberosity on medial humerus (common with latissimus dorsi)
Function: Flexes shoulder joint and adducts limb.
📚 DETAILED DESCRIPTION:
THE CAUDAL MEDIAL FLEXOR
Located on the medial aspect just caudal to the shoulder joint, forming a functional unit with the latissimus dorsi (shared insertion).
ORIGIN SITES: Arises from the caudal angle (distal tip) and caudal border of the scapula, giving it a caudal line of pull compared to other shoulder flexors.
SYNERGISTIC INSERTION: Inserts via common tendon with latissimus dorsi on the teres major tuberosity. This combined insertion creates one of the most powerful retractor/adductor complexes in the body.
QUADRANGULAR SPACE: Forms the caudal boundary of the quadrangular space through which the axillary nerve passes. Surgical approaches to the axillary nerve or shoulder must account for teres major position.
FUNCTION: Flexes the shoulder (drawing limb forward/upward) and adducts the limb toward the body wall.
// COMPARATIVE ANALYSIS
| HORSE |
Similar position; also shares tendon with latissimus. |
| DOG |
More distinct separation from latissimus insertion. |
CLINICAL RELEVANCE
Caudal Dislocation: Helps resist caudal displacement of humeral head; injury allows caudal 'slipping'.
