VIDEO
CONTENT
QUIZ
MATERIALS
Quick Facts
Key Features
Origin
Insertion
Actions
Clinical Correlates
Arterial Supply
Innervation
Quick Facts:
- Origin: Posterior aspect of superior half of lateral border of scapula.
- Insertion: Greater tubercle of humerus.
- Action: Laterally rotates, transversely abducts, and stabilizes the arm at the glenohumeral (shoulder) joint.
- Innervation: Axillary nerve (C5-C6).
- Arterial Supply: Circumflex scapular and posterior circumflex humeral arteries.
Key Features & Anatomical Relations:
- The teres minor muscle is one of the rotator cuff muscles.
- It is located:
- Anterior (deep) to the clavicular part of the deltoid muscle.
- Posterior (superficial) to the scapula, and the long head of the triceps brachii muscle.
- Superior to the teres major muscle.
- Inferior to the infraspinatus muscle.
Origin:
- The teres minor muscle originates from the posterior aspect of the superior half of the lateral border of the scapula and its adjacent area.
Insertion:
- The fibers of the teres minor muscle travel superolaterally and insert, via a short tendon, onto the inferior facet of the greater tubercle of the humerus. Part of this tendon also merges with the capsule of the glenohumeral (shoulder) joint.
Actions:
- The teres minor muscle is involved in multiple actions:
- Laterally rotates the arm at the glenohumeral (shoulder) joint.
- Transversely abducts the arm at the glenohumeral joint (i.e., it abducts the flexed arm along the transverse plane).
- Assists in adduction of the arm at the glenohumeral joint.
- It is one of the four rotator cuff (SITS) muscles, with the other three being the supraspinatus, infraspinatus, and subscapularis muscles. These muscles work together to stabilize the glenohumeral joint by holding the head of the humerus in the glenoid fossa of the scapula during its movements.
List of Clinical Correlates:
- Injury or rupture of the rotator cuff.
Arteria circumflexa posterior humeri
- Origin: Axillary artery (third part).
- Course: Posteriorly with the axillary nerve, through the quadrangular space, to the posterior aspect of the humerus.
- Branches: Anastomoses with the anterior circumflex humeral artery.
- Supplied Structures: Deltoid, teres major, teres minor, long and lateral heads of the triceps brachii muscles, glenohumeral joint, cutaneous supply to the area posterolateral to the proximal humerus.
Arteria circumflexa scapulae
- Origin: Subscapular artery.
- Course: Along lateral scapular border into infraspinous fossa.
- Branches: Unnamed branches.
- Supplied Structures: Posterior portion of the teres major and minor muscles, deltoid muscle, long head of the triceps brachii muscle, scapula, skin overlying the scapula.
Nervus axillaris
- Origin: Subscapular artery.
- Course: Along lateral scapular border into infraspinous fossa.
- Branches: Unnamed branches.
- Supplied Structures: Posterior portion of the teres major and minor muscles, deltoid muscle, long head of the triceps brachii muscle, scapula, skin overlying the scapula.
