muscles that cross the shoulder joint: humerus Flashcards
Latissimus dorsi muscle
O: spinous processes of t7-l5 vertebrae, iliac crest of sacrum, thoracolumbar fascia, inferior angle of the scapula, lower three or four ribs I: floor of intertubercular (bicipital) groove of humorous N: thoracodorsal nerve. Root: c6, c7, c8 K: Adducts the arm at the GH joint, medially rotates the arm at the GH joint, extends the arm at the GH joint
Pectoralis major muscle
O: clavicular head: at the medial half of the clavicle. Sternal head: at the sternum, upper costal cartilage (1-6) and the aponeurosis of the external oblique I: lateral lip of the intertubercular (bicipital) groove of the humorous. Crest of the greater tubercle of the humerus. N: c5, c6, c7 lateral pectoral nerve to the clavicular head. C8,t1 medial pectoral nerve to the sternal head K: clavicular head flexes the arm at the GH joint. Sternal head extends the arm at the GH joint from a flexed position. Both heads medially rotate the arm at the GH joint and adduct the arm at the GH joint
Deltoid muscle – anterior and middle heads
O: anterior head: anterior surface of the lateral clavicle. Middle head: Acromion process of the spine of the scapula I: deltoid tuberosity of the humorous N: axillary nerve. Roots: c5, c6 K: The anterior head flexes the arm at the shoulder and medially rotates the arm at the shoulder. The middle head abducts the arm at the shoulder.
Deltoid muscle – posterior head
O: spine of scapula I: deltoid tuberosity of humorous N: axillary nerve. Root: c5,c6 K: Laterally rotates the arm of the GH joint, extends the arm at the GH joint
Supraspinatus
O: supraspinus fossa of scapula I: superior aspect of greater tubercle of humerus N: suprascapular nerve. Root: c5and c6 K: abduction of arm at gh joint, stabilize shoulder by drawing humerus toward glenoid fossa of scapula
Infraspinatus muscle
O: infraspinous fossa of the scapula I: middle part of the greater tubercle of the humerus N: suprascapular nerve. Root: c5 and c6 K: laterally rotates the arm at the gh joint, stabilizes shoulder joint
Teres minor muscle
O: middle part of the lateral border of the scapula I: inferior aspect of the greater tubercle of humerus N: axillary nerve. roots: c5 and c6 K: laterally rotates the arm at the gh joint, weakly adducts the arm at the gh joint, stabilizes shoulder
Teres major muscle
O: lower lateral border and inferior angle of scapula I: medial lip of the intertubercular (bicipital) groove of the anterior humerus N: lower scapular nerve. Root: c5,c6, c7 K: adducts the arm at gh joint, medially rotates the arm at the GH joint, extends the arm at the GH joint
Subscapularis muscle
O: subscapular fossa of the scapula I: lesser tubercle of humerus N: upper and lower subscapular nerves root: c5,c6,c7 K: medially rotates the arm at the GH joint
Coracobrachialis muscle
O: coracoid process of the scapula I: mid medial surface of the humorous N: Musculocutaneous nerve. Root: C5, C6, C7 K: flexes the arm at the GH joint, adducts the arm at the GH joint
