Teres muscle

The teres muscles are two muscles of the shoulder that connect the scapula to the humerus. These muscles are the teres major muscle and the teres minor muscle.

Teres Major Muscle

The teres major muscle is a thick, flattened muscle that originates from the lower part of the scapula and inserts into the medial lip of the intertubercular sulcus of the humerus. It is primarily responsible for the adduction and medial rotation of the arm. The teres major is innervated by the lower subscapular nerve and receives blood supply from the circumflex scapular artery.

Teres Minor Muscle

The teres minor muscle is a narrow, elongated muscle that originates from the lateral border of the scapula and inserts into the greater tubercle of the humerus. It is part of the rotator cuff and is involved in the lateral rotation of the arm. The teres minor is innervated by the axillary nerve and also receives blood supply from the circumflex scapular artery.

Function

The teres muscles play a crucial role in the movement and stabilization of the shoulder joint. The teres major muscle assists in adduction and medial rotation of the arm, while the teres minor muscle is involved in lateral rotation and stabilization of the humerus within the glenoid cavity.

Clinical Significance

Injuries to the teres muscles can affect shoulder movement and stability. The teres minor muscle is particularly important in maintaining the integrity of the rotator cuff, and damage to this muscle can lead to rotator cuff tears or shoulder impingement syndrome.

See Also

• Rotator cuff
• Shoulder joint
• Scapula
• Humerus

References

• Gray's Anatomy
• Netter's Atlas of Human Anatomy