Anterior Shoulder - Axilla and Arm Muscles Flashcards
Pectoralis Major- Clavicular Head Origin
Anterior surface of medial half of clavicle
Pectoralis Major- Clavicular Head Insertion
Lateral lip intertubercular sulcus of humerus
Pectoralis Major- Clavicular Head Innervation
Lateral and medial pectoral nerves; clavicular head (C5,C6), sternocostal head (C7,C8,T1)
Pectoralis Major- Clavicular Head Action
Both heads adducts and medially rotates humerus; draws scapula anteriorly and inferiorly. Clavicular head flexes humerus
Pectoralis Major- Sternocostal Head Origin
Anterior surface of sternum, superior six costal cartilages, aponeurosis of external oblique muscle
Pectoralis Major- Sternocostal Head Insertion
Lateral lip intertubercular sulcus of humerus
Pectoralis Major- Sternocostal Head Innervation
Lateral and medial pectoral nerves; clavicular head (C5,C6), sternocostal head (C7,C8,T1)
Pectoralis Major- Sternocostal Head Action
Both heads adducts and medially rotates humerus; draws scapula anteriorly and inferiorly. Sternocostal head extends it from the flexed position
Serratus Anterior Origin
External surfaces of lateral parts of 1st-8th ribs
Serratus Anterior Insertion
Anterior surface of medial border of scapula
Serratus Anterior Innervation
Long thoracic nerve
Serratus Anterior Action
Protracts scapula and holds it against thoracic wall; rotates scapula
Serratus Anterior Root
C5,C6,C7
Subclavius Origin
Junction of 1st rib and its costal cartilage
Subclavius Insertion
Inferior surface of middle third of clavicle
Subclavius Innervation
Nerve to subclavius (C5,C6)
Subclavius Root
C5,C6
Coracobrachialis Origin
Tip of coracoid process of scapula
Coracobrachialis Insertion
Middle third of medial surface of humerus
Coracobrachialis Innervation
Musculocutaneous nerve (C5,C6,C7)
Coracobrachialis Action
Helps flex and adduct arm; resists dislocation of shoulder
Biceps Brachii - Short Head Origin
Tip of coracoid process of scapula
Biceps Brachii - Short Head Insertion
Tuberosity of radius and fascia of forearm via bicipital aponeurosis
Biceps Brachii - Short Head Innervation
Musculocutaneous nerve (C5,C6,C7)
Biceps Brachii - Short Head Action
Supinates forearm and, when it is supinated, flexes elbow, short head resists dislocation of shoulder
Biceps Brachii - Long Head Origin
Supraglenoid tubercle of scapula
Biceps Brachii - Long Head Insertion
Tuberosity of radius and fascia of forearm via bicipital aponeurosis
Biceps Brachii - Long Head Innervation
Musculocutaneous nerve (C5,C6,C7)
Biceps Brachii - Long Head Action
Supinates forearm and, when it is supinated, flexes elbow
Brachialis Origin
Distal half of anterior surface of humerus
Brachialis Insertion
Coronoid process and tuberosity ulna
Brachialis Innervation
Musculocutaneous nerve (C5,C6) and radial nerve(C5,C7)
Brachialis Action
Flexes forearm in all positions
Triceps Brachii - Long Head Origin
Infraglenoid tubercle of scapula
Triceps Brachii - Long Head Insertion
Proximal end of olecranon of ulna and fascia of forearm
Triceps Brachii - Long Head Innervation
Radial nerve (C6,C7,C8)
Triceps Brachii - Long Head Action
Chief extensor of forearm; long head resists dislocation of humerus; especially important during adduction
Triceps Brachii - Lateral Head Origin
Posterior surface of humerus, superior to radial groove
Triceps Brachii - Lateral Head Insertion
Proximal end of olecranon of ulna and fascia of forearm
Triceps Brachii - Lateral Head Innervation
Radial nerve (C6,C7,C8)
Triceps Brachii - Lateral Head Action
Chief extensor of forearm; long head resists dislocation of humerus; especially important during adduction
Triceps Brachii - Medial Head Origin
Posterior surface of humerus, inferior to radial groove
Triceps Brachii - Medial Head Insertion
Proximal end of olecranon of ulna and fascia of forearm
Triceps Brachii - Medial Head Innervation
Radial nerve (C6,C7,C8)
Triceps Brachii - Medial Head Action
Chief extensor of forearm; long head resists dislocation of humerus; especially important during adduction
Anconeus Origin
Lateral epicondyle of humerus
Anconeus Insertion
Lateral surface of olecranon and superior part of posterior surface of ulna
Anconeus Innervation
Radial nerve (C7,C8,T1)
Anconeus Action
Assists triceps in extending forearm; stabilizes elbow joint; may abduct ulna during pronation
costoclavicular impression is at what end of clavicle
sternal
humeral condyle is made up by blank and blank
capitulum, trochlea
capitulum is blank
lateral
trochlea is blank
medial
radial fossa is blank
lateral
coronoid fossa is blank
medial
axillary artery becomes blank artery
brachial
terminal branches of brachial plexus are all blank innervation
cutaneous
Pectoralis minor origin
3-5 ribs near costal cartilages
Pectoralis minor insertion
Medial and superior surface of coracoid process
Pectoralis minor innervation
Medial pectoral nerve (C8, T1)
Pectoralis minor action
Stabilize scapula by drawing it inferiorly and anteriorly on thoracic wall
Subclavius action
Anchors and depresses clavicle