Competency Flashcards
Brachialis
O: Distal half of anterior aspect of the humerus (medial and lateral surfaces) and adjacent intermuscular septae
I: Coronoid process and tuberosity of ulna
A: Flexion at elbow in all positions
N: Musculocutaneous (C5, C6)
Coracobrachialis
O: Apex of coracoid process
I: Linear roughening on medial midshaft of humerus;
A: flex and adduct at the GH joint
N: Musculocutaneous nerve (C5, C6, C7)
Brachioradialis
O: Proximal 2/3 of lateral supracondylar ridge of humerus and adjacent intermuscular septum
I: Styloid process of radius
A: Accessory flexion of elbow (humero-ulnar) joint when forearm is midpronated; assist with pronation and supination of the forearm with resistance (weak)
N: radial nerve (C5, C6, C7) before division into superficial and deep branches
Triceps brachii
O: Long head - infraglenoid tubercle of scapula
Medial head - posterior surface of the distal half of humerus (distal to radial groove)
Lateral head - posterior surface of the proximal half of humerus (superior to radial groove)
I: Olecranon
A: All heads: extension at elbow joint. Long head: extend and adduct at the GH joint
N: radial nerve (C6, C7, C8)
Deltoid (anterior fibers)
O: Anterior border of the lateral 1/3 of clavicle
I: Deltoid tuberosity of the humerus
A: Abduct, flexion, horizontal adduction, and internal rotation of the humerus
N: Axillary (C5, C6)
Deltoid (middle fibers)
O: Lateral margin of the acromion
I: Deltoid tuberosity of the humerus
A: abduct at GH joint
N: Axillary (C5, C6)
Deltoid (posterior fibers)
O: Inferior edge of the crest of the spine of the scapula
I: Deltoid tuberosity of the humerus
A: Abduct, extension, horizontal abduction, and external rotation at the GH joint
N: Axillary (C5, C6)
Latissimus dorsi
O: Spinous processes of T7-T12 and related interpinous ligaments; via the thoracolumbar fascia to the spinous process of the lumbar vertebrae, related interspinous ligaments, and posterior iliac crest; last three or four ribs, inferior angle of the scapula
I: Floor of the intertubercular sulcus (or groove)
A: Adduction, medial rotation, & extension at GH joint
N: Thoracodorsal nerve (C6,C7,C8)
Teres major
O: Lower one third of lateral border of the scapula
I: Medial lip of intertubercular sulcus on the anterior surface of the humerus; crest of the lesser tubercle of the humerus
A: Medial rotation, extension, & adduction at the GH joint
N: lower subscapular nerve (C5, C6)
Trapezius (superior fibers)
O: External occipital protuberance, the medial portion of superior nuchal line of occiput, medial margin of ligamentum nuchae,
I: Posterior border of lateral 1/3 of the clavicle
A: Unilaterally: Elevation and upper rotation of the scapula; ipsilateral side bending (laterally flex) and contralateral rotation of the head;
Bilaterally: extend the head and neck
N: Accessory nerve (CN XI) and branches of C3, C4
Trapezius (middle fibers)
O: Inferior aspect of ligamentum nuchae, spinous proces of 7th cervical and upper thoracic
I: Medial margin of acromion process of scapula, superior lip of posterior border of spine of
scapula
A: Retract, adduct, & stabilize scapula
N: CN XI and C3, C4
Trapezius (inferior fibers)
O: Spinous process of inferior thoracic vertebrae
I: Medial end of the spine of scapula
A: Depression & upwardly rotate the scapula
N: CN XI and C3, C4
Levator scapula
O: Transverse processes of C1-C4 vertebrae at the posterior tubercles
I: Posterior surface of medial border of scapula from superior angle to root of spine of the scapula
A: Unilaterally: Elevates scapula; ipsilateral side bending and ipsilateral rotation of the head, downwardly rotate the scapula
Bilaterally: extend the head and neck
N: Anterior rami of C3 and C4 spinal nerves and by branches (C5) from the dorsal scapular nerve
Pectoralis major
O: Clavicular head - anterior surface of medial half of clavicle;
Sternocostal head - anterior surface of the sternum; first seven costal cartilages; sternal end of the sixth rib; aponeurosis of external oblique
I: Lateral lip of the intertubercular sulcus of humerus; crest of greater tubercle of humerus
A: All fibers: adduct, horizontal adduct & medial rotation at the GH joint; assist to elevate the thorax during forced inhalation with arm
Clavicular head: flexion of the extended shoulder
Sternocostal head: extension of the flexed shoulder
N: Medial and lateral pectoral nerves (C5-T1)
Clavicular head: lateral pectoral (C5, C6)
Sternocostal head: lateral and medial pectoral nerves (C7, C8, T1)
Pectoralis minor
O: Anterior surface of the superior borders of third to fifth ribs; and from deep fascia overlying the
related intercostal spaces
I: Coracoid process of scapula (medial border and upper surface)
A: Stabilization of the scapula against thoracic wall by pulling the coracoid process anteriorly,
downward rotation of the scapula; depression of the scapula, abduction of the scapula,
N: Medial pectoral nerve (C8, T1) (some with fibers from the communicating branch of the lateral pectoral nerve C6, C7,C8,T1)