Scapulohumeral Muscles Flashcards
Which muscles are in the scapulohumeral muscle group?
Deltoid, subscapularis, supraspinatus, infraspinatus, teres minor and major
What are the attachment sites for the deltoid muscle?
O: lateral 1/3 clavicle, scapular spine and acromion
I: deltoid tuberosity of humerus
What are the actions of the deltoid muscle?
Anterior part flexes and medial rotates the humerus
Middle part abducts the humerus
Posterior part extends and laterally rotates the humerus
Which muscles are innervated by the axillary nerve?
Deltoid and teres minor
What are the attachment sites for subscapularis?
O: medial aspect of the subscapular fossa
I: lesser tubercle of humerus
What is the action of subscapularis?
Medially rotate and adduct the humerus
Holds the humeral head in the glenoid cavity
Which muscles are innervated by the suprascapular nerve?
Supraspinatus, infraspinatus
What innervates subscapularis?
Upper and lower subscapular N
What are the attachment sites for supraspinatus?
O: supraspinous fossa of scapula
I: greater tubercle of humerus
What is the action of supraspinatus?
Within the deltoid muscle abduct the humerus
Holds the humeral head in the glenoid cavity
What are the attachment sites for infraspinatus?
O: infraspinous fossa of scapula
I: greater tubercle of humerus
What is the action of infraspinatus?
Laterally rotates the humerus
Holds the humeral head in the glenoid cavity
What are the attachment sites for teres minor?
O: middle part of the lateral border of the scapula
I: greater tubercle of the humerus
What is the action of teres minor?
Laterally rotates the humerus
Holds the humeral head in the glenoid cavity
What are the attachment sites for teres major?
O: posterior aspect of the inferior angle of scapula
I: medial edge of the intertubercular groove of humerus
