Scapular Muscles Flashcards
Origin of the Deltoid
- Anterior: Clavicular portion from clavicle
- Middle: Acromial portion from scapula
- Posterior: Spinous portion from scapula
Insertion of the Deltoid
- Deltoid tuberosity/humerus
Action of the Deltoid
- Anterior: Flexes and medially rotates humerus
- Middle: Abducts humerus
- Posterior: Extends and laterally rotates humerus
Nerve supply of the Deltoid
- Axillary nerve
Origin of the Supraspinatus
- Supraspinatus fossa/scapula
Insertion of the Supraspinatus
- Greater tuberosity/humerus
Action of the Supraspinatus
- Initiates abduction of the humerus
- Helps laterally rotates humerus
- Helps stabilize humerus
Nerve supply of the Supraspinatus
- Suprascapular nerve
Origin of the Infraspinatus
- Infraspinatus fossa/humerus
Insertion of the Infraspinatus
- Greater tuberosity/humerus
Action of the Infraspinatus
- Laterally rotates humerus
- Stabilizes scapula
Nerve suppy of the Infraspinatus
- Suprascapular nerve
Origin of the Subscapularis
- Subscapular fossa/scapula
Insertion of the Subscapularis
- Lesser tuberosity/humerus
Action of the Subscapularis
- Stabilization of the shoulder joint
- Medially rotates humerus
Nerve supply of the Subscapularis
- Upper and lower subscapular nerve
Origin of the Teres Major
- Inferior angle/scapula
Insertion of the Teres Major
- Intertubercular groove
Action of the Teres Major
- Adducts humerus
- Stabilizes shoulder joint
- Medially rotates humerus
Nerve supply of the Teres Major
- Lower subscapular nerve
Origin of the Teres Minor
- Axillary border/scapula
Insertion of the Teres Minor
- Greater tuberosity/humerus
Action of the Teres Minor
- Laterally rotates humerus
- Stabilizes shoulder joint
Nerve supply of the Teres Minor
- Axillary nerve