Scapulohumeral Muscles Flashcards
Insertion of Deltoid?
Deltoid tuberosity of humerus
Origin of Deltoid?
Lateral third of clavicle, acromion and spine of scapula
Innervation of Deltoid?
Axillary Nerve (C5, C6)
Actions of Deltoid?
Clavicular (anterior) part flexes and medially rotates shoulder joint, acromial (middle) part abducts shoulder joint; spinal (posterior) part extends and laterally rotates the shoulder
Origin of Supraspinatus?
Supraspinous fossa of scapula
Insertion of Supraspinatus?
Superior facet of greater tubercle of humerus
Innervation of Supraspinatus?
Suprascapular nerve (C4, C5, C6)
Action of Supraspinatus?
Initiates and assists deltoid in abduction of shoulder joint and acts with other rotator cuff muscles
Infraspinatus Origin?
Infraspinous fossa of scapula
Infraspinatus Insertion?
Middle facet of greater tubercle of humerus
Innervation of Infraspinatus?
Suprascapular nerve (C5, C6)
Infraspinatus action?
Laterally rotate the shoulder joint; help hold humeral head in glenoid cavity of scapula
Teres Minor Origin?
Middle part of lateral border of scapula
Teres minor insertion?
Inferior facet of greater tubercle of humerus
Innervation of Teres minor?
Axillary nerve (C5, C6)
Action of Teres Minor?
Laterally rotate the shoulder joint; help hold humeral head in glenoid cavity of scapula
Teres Major origin?
Inferior part of lateral border of scapula and posterior surface of inferior angle of scapula
Teres major insertion?
Medial lip of intertubercular sulcus of humerus
Innervation of Teres Major?
Lower subscapular nerve (C5, C6)
Actions of Teres major?
Adducts and medially rotates the shoulder joint
Subscapularis Origin?
Subscapular fossa (most of anterior surface of scapula)
Insertion of subscapularis?
Lesser tubercle of humerus
Innervation of Subscapularis?
Upper and lower sub-scapular nerves (C5, C6, C7)
Subscapularis Actions?
Medially rotates and adducts shoulder joint; helps hold humeral head in glenoid cavity.
