Musculus teres major
The teres major is a powerful muscle on the caudal scapula. It originates from the caudal angle of the scapula and adjacent scapular cartilage and inserts on the teres major tuberosity on the medial humerus (with the latissimus dorsi). Its actions are to flex the shoulder, medially rotate the humerus, and retract the forelimb. It is innervated by the subscapular nerves (roughly C7-C8). It 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)
Isolated injury is uncommon. Relevant in evaluations of shoulder function and after trauma.
## Overview The teres major helps retract and stabilize the shoulder and is heavily loaded during collection and half-halts. Strain produces a shortened forelimb stride, pain at the caudal border of
Sudden shoulder swelling or reduced limb retraction after trauma should be evaluated.
## Overview The teres major helps retract and stabilize the shoulder and is heavily loaded during collection and half-halts. Strain produces a shortened forelimb stride, pain at the caudal border of the scapula, reluctance to perform half-halts or downward transitions, and stiffness in collected work. ## Causes Overuse during collected work. ## Diagnosis Palpation and observation under saddle. ## Treatment Rest from collected work, physiotherapy, and gradual return. ## Recovery and Prognosis Good. ## Prevention Progressive development of collection. Signs include: shortened forelimb stride; pain on palpation at the caudal border of the scapula; reluctance to half-halt or perform downward transitions; stiffness in collected work
Isolated injury is uncommon. Relevant in evaluations of shoulder function and after trauma.
Sudden shoulder swelling or reduced limb retraction after trauma should be evaluated.
See the Teres Major on our interactive 3D horse model. Open 3D Model