Muscles of the Shoulder Flashcards
Deltoid origin
- spine of scapula 2. acromion 3. lateral 1/3 of clavicle
Deltoid insertion
- deltoid tuberosity of humerus
Deltoid innervation
axillary nerve
Deltoid action
- abducts arm 2. anterior fibers can flex arm 3. posterior fibers can extend arm
Supraspinous origin
supraspinous fossa
Supraspinous insertion
greater tubercle of humerus (middle part)
Supraspinous innervation
suprascapular nerve
Supraspinous action
- abducts arm 2. initiates abduction
Infraspinous origin
infraspinous fossa
Infraspinous insertion
greater tubercle of humerus (middle part)
Infraspinous innervation
suprascapular nerve
Infraspinous action
laterally rotates arm
Teres minor origin
lateral border of scapula (upper half)
Teres minor insertion
greater tubercle of humerus (inferior part)
Teres minor innervation
axillary nerve
Teres minor action
laterally rotates arm
Teres major origin
lateral border of scapul a(lower half and inferior angle)
Teres major insertion
anterior side of humerus (medial lip of intertubercular groove)
Teres major innervation
lower subscapular nerve
Teres major action
extends and medially rotates arm
Triceps origin
long head: infraglenoid tubercle of scapula laterla head: posterior humerus superior to radial groove medial head: posterior humerus inferior to radial groove
Triceps insertion
olegranon process of the ulna
Triceps innervation
radial nerve
Triceps action
- extends forearm 2. long head can extend arm
