Upper extremity Flashcards
Insertion of the pectoralis major
Lateral lip of the intertubercular sulcus of humerus
Origin of the pectoralis major
(clavicular head) anterior surface of medial half of clavicle
(Sternocostal head) anterior surface of sternum, superior 6 costal cartilages, aponeurosis of external oblique muscle
Innervation of the pectoralis major
Lateral and medial pectoral nerves
Clavicular hear- C5 and C6
Sternocostal head C7, C8, T1
Actions of the pectoralis major
Adducts and medially rotates humerus; draws scapula anteriorly and inferiorly. Acting alone, clavicular head flexes humorus and sternocostal head extends it from the flexed position.
Origin of the pectoralis minor
3rd-5th ribs near their costal cartilages
Insertion of the pectoralis minor
Medial border and superior surface of the coracoid process of the scapula
Actions of the pectoralis minor
Stabilizes scapula by drawing inferiorly and anteriorly against the thoracic wall
Origin of the subclavius
Junction if the 1st rib and its coastal cartilage
Insertion of the subclavius
Inferior surface of the middle third of the clavicle
Innervation of the subclavius
Subclavian nerve (C5, C6)
Actions of the subclavius
Anchors and depresses the clavicle
Origin of the serratus anterior
External surface of the lateral parts of the 1st-8th ribs
Insertion of the serratus anterior
Anterior surface of the medial border of the scapula
Innervation of the serratus anterior
Long thoracic nerve (C5, C6, C7)
Actions of the serratus anterior
Protracts the scapula
Fixes it to the thoracic wall
Rotates the scapula
Innervation of the pectoralis minor
Medial pectoral nerve (C8-T1)
Origin of the trapezius
Medial third of the superior nuchal line
External occipital protuberance
Nuchal ligament
Spinous processes of C7-T12
Insertion of the trapezius
Lateral third of the clavicle
The acromion
The spine of the scapula
Innervation of the trapezius
Spinal accessory nerve (CN XI) (motor)
C3 + C4 (pain and proprioception)
Actions of the trapezius
Descending (superior) part elevates
Ascending (inferior) part depresses
Middle part retracts
Descending and ascending work together to rotate glenoid cavity
Origin of the latissimus dorsi
Spinous processes of inferior 6 thoracic vertebrae
Thoracolumbar fascia
Iliac crest
Inferior 3 or 4 ribs
Insertion of the latissimus dorsi
Floor of the intertubercular sulcus of the humerus
Innervation of the latissimus dorsi
Thoracodorsal nerve (C6, C7, C8)
Actions of the latissimus dorsi
Extends, adducts, and medially rotates humerus
Raises body towards arms during climbing
Origin of the deltoid
Lateral third of the clavicle
The acromion
The spine of the scapula
Insertion of the deltoid
The deltoid tuberosity of the humerus
Innervation of the deltoid
Axillary nerve (C5, C6)
Actions of the deltoid
Clavicular (anterior) part flexes and medially rotates arm
Acromial (middle) part abducts arm
Spinal (posterior) part extends and laterally rotates arm
Origin of the levator scapulae
Posterior tubercles of the transverse processes of C1-C4 vertebrae
Insertion of the levator scapulae
Medial border of the scapula superior to the root of the spine
Innervation of the levator scapulae
Dorsal scapular nerve (C5) Cervical nerves (C3-C4)
Actions of the levator scapulae
Elevates scapula and tilts its glenoid cavity inferiorly by rotating the scapula
Origin of the infraspinatus
Infraspinatus fossa
Insertion of the infraspinatus
Middle facet of the greater tubercle of the humerus
Innervation of the infraspinatus
Suprascapular nerve (C4, C5, C6)
Actions of the infraspinatus
Laterally rotates arm
Helps hold humeral head in glenoid cavity of scapula
Origin of the teres minor
Middle part of the lateral border of scapula
Insertion of the teres minor
Inferior facet of the greater tubercle of the humerus
Innervation of the teres minor
Axillary nerve (C5, C6)
Actions of the teres minor
Laterally rotates arm
Helps hold humeral head in the glenoid cavity of the scapula
Origin of the teres major
Posterior surface of the inferior angle of the scapula
Insertion of the teres major
Medial lip of the intertubercular sulcus of the humerus
Innervation of the teres major
Lower subscapular nerve (C5, C6)
Actions of the teres major
Adducts and medially rotates arm
Origin of the subscapularis
Subscapular fossa (most of anterior surface of scapula)
Insertion of the subscapularis
Lesser tubercle of the humerus
Innervation of the subscapularis
Upper and lower subscapular nerve (C5, C6, C7)
Actions of the subscapularis
Medially rotates and adducts arm
Helps hold the humeral head in the glenoid cavity
Origin of the coracobrachialis
Tip of the coracoid process of the scapula
Insertion of the coracobrachialis
Middle third of the medial surface of the humerus
Innervation of the coracobrachialis
Musculocutaneous nerve (C5, C6)
Actions of the coracobrachialis
Helps flex and adduct arm
Resists dislocation of shoulder
Origin of triceps brachii
Long head: infraglenoid tubercle of the scapula
Lateral head: posterior surface of the humerus, superior to the radial groove
Medial head: posterior surface of the humerus, inferior to the radial groove
Insertion of the triceps brachii
Proximal end of the olecranon of the ulna and fascia of the forearm
Innervation of the triceps brachii
Radial nerve (C6, C7, C8)
Actions of the triceps brachii
Chief extensor of the forearm
Long head extends arm and resists dislocation of humerus (especially important during abduction)
Origin of the anconeus
Lateral epicondyle of the humerus
Insertion of the anconeus
Lateral surface of the olecranon and superior part of the posterior surface of the ulna
Innervation of the anconeus
Radial nerve (C7, C8, T1)
Action of the anconeus
Assists triceps in extending the forearm
Stabilizes elbow joint
Abducts ulna during pronation
Origin of the pronator teres
Ulnar head: Coronoid process of the ulna
Humeral head: medial epicondyle of the humerus
Insertion of the pronator teres
Middle convexity of lateral surface of radius
Innervation of the pronator teres
Median nerve (C6, C7)
Actions of the pronator teres
Pronates and flexes the forearm (at elbow)
Origin of the flexor carpi radialis (FCR)
Medial epicondyle of the humerus