Musculus teres major
A powerful muscle on the caudal scapula that flexes and medially rotates the shoulder. Works with the latissimus dorsi to retract the forelimb during the propulsive phase of the stride.
Origin: Caudal angle of the scapula and adjacent scapular cartilage
Insertion: Teres major tuberosity on the medial humerus (with latissimus dorsi)
Action: Flexes the shoulder; medially rotates the humerus; retracts the forelimb
Innervation: Subscapular nerves (C7-C8)
Heavy collection and half-halts load this muscle significantly as it helps retract and stabilize the shoulder.
Heavy collection and half-halts load this muscle significantly as it helps retract and stabilize the shoulder. Signs include: Shortened forelimb stride; pain on palpation at the caudal border of the scapula; reluctance to perform half-halts or downward transitions; stiffness in collected work.
See the Teres Major on our interactive 3D horse model. Open 3D Model