Unit 3 Flashcards
Extensor Pollicis Longus
O: Posterior surface of ulna and interosseous membrane
I: Base of distal phalanx of thumb
N: Posterior interosseous nerve (Radial; C6-C8)
A: Extend thumb (IP, MCP, CMC joints); abduct wrist
Rhomboid minor
O: Spinous processes of C7-T1; nuchal ligament
I: Upper portion of medial border of scapula, across from spine of scapula
N: Dorsal scapular C4-C5
A: Adduct the scapula (scapulothoracic joint), elevate the scapula (S/T joint), downwardly rotate scapula (S/T joint)
Flexor Carpi Radialis
O: Common flexor tendon from medial epicondyle of humerus
I: Bases of 2nd/3rd metacarpals
N: Median (C6-C8)
A: Flex the wrist, abduct the wrist, may assist to flex elbow
Extensor Carpi Radialis Longus
O: Distal 1/3 of the lateral supracondylar ridge of humerus
I: base of 2nd metacarpal
N: Radial nerve (C5-C8)
A: Extend wrist, abduct wrist, assist to flex the elbow
Trapezius
O: External occipital protuberance, medial portion of superior nuchal line of the occiput, ligamentum nuchae, and spinous processes of C7-T12
I: Lateral 1/3 of clavicle, acromion, and spine of the scapula
N: Spinal portion of Cranial nerve XI (accessory) and ventral ramus of C2-4
A: Upper fibers
Bilaterally - Extend the head and neck
Unilaterally - Ipsilateral lateral flexion of head/neck; Contralateral rotation of head/neck; elevate the scapula (scapulothoracic joint); upwardly rotate the scapula (S/T joint)
Middle fibers - Adduct the scapula (S/T joint); Stabilize (S/T joint)
Lower fibers - Depress the scapula (S/T joint); upwardly rotate the scapula (S/T joint)
Serratus Anterior
O: External surfaces of upper 8-9 ribs
I: Anterior surface of medial border of scapula
N: Long thoracic C5, 6, 7, 8
A:
With the origin fixed - Abducts the scapula (scapulothoracic joint), upwardly rotates the scapula (S/T joint), Depress the scapula (S/T joint), Hold the medial border of the scapula against the rib cage
With the scapula fixed - May act to elevate the thorax during forced inhalation
Subscapularis
O: Subscapular fossa of scapula
I: Lesser tubercle of humerus
N: Upper and lower subscapular C5-C7
A: Medially rotate shoulder (glenohumeral joint), stabilize head of humerus in glenoid cavity
Flexor Carpi Ulnaris
O: (Humeral head) - Common flexor tendon from medial epicondyle of humerus
(Ulnar head) - Posterior surface of proximal two-thirds of ulna
I: Pisiform, hook of hamate, and base of fifth metacarpal
N: Ulnar (C7-T1)
A: Flex the wrist, adduct the wrist (ulnar deviation), assist to flex elbow
Supinator
O: Lateral epicondyle of Humerus, radial collateral ligament, annular ligament, supinator crest of ulna
I: Anterior, lateral surface of proximal 1/3 of radial shaft
N: Deep branch of Radial nerve (C5-C7)
A: Supinate forearm
Flexor Digitorum Superficialis
(2nd layer)
O: Common flexor tendon from medial epicondyle of humerus, ulnar collateral ligament, coronoid process of ulna, interosseous membrane, and proximal shaft of radius
I: Sides of middle phalanges of 2nd to 5th fingers
N: Median (C7-T1)
A: Flex 2nd-5th fingers (MCP and distal IP joints); assist to flex wrist
Biceps Brachii
O: Short head - Coracoid process of scapula
Long head - Supraglenoid tubercle of scapula
I: Tuberosity of the radius and aponeurosis of the biceps brachii
N: Musculocutaneous (C5, C6)
A: Flex the elbow (humeroulnar joint), supinate the forearm (radioulnar joints), flex the shoulder (glenohumeral joint)
Abductor Pollicis Longus
O: Posterior surface of radius and ulna, interosseous membrane
I: Base of 1st metacarpal
N: Posterior interosseous nerve (Radial; C6-C8)
A: Abduct thumb (CMC), extend thumb (CMC), abduct wrist
Flexor Digitorum Profundus
(3rd layer)
O: Anterior and medial surfaces of proximal 3/4 of ulna and interosseous membrane
I: Bases of distal phalanges, palmar surface of digits 2-5
N: (2nd and 3rd finger) - Median (C7-T1)
(4th and 5th finger) - Ulnar (C7-T1)
A: Flex 2-5 fingers (MCP, Distal IP joints); assist to flex wrist
Extensor Carpi Ulnaris
O: Lateral Epicondyle of Humerus (common extensor tendon)
I: Base of 5th metacarpal bone
N: Deep branch of Radial nerve (C6-C8)
A: Extend wrist, adduct wrist (ulnar deviation)
Infraspinatus
O: Infraspinous fossa of scapula
I: Greater tubercle of humerus
N: Suprascapular C4-C6
A: Laterally rotate the shoulder (glenohumeral joint), adduct shoulder (G/H joint), stabilize head of humerus in glenoid cavity
Brachialis
O: Distal half of anterior surface of humerus
I: Tuberosity and coronoid process of ulna
N: Musculocutaneous, small branch from radial (C5, C6)
A: Flex the elbow (humeroulnar joint)
Pectoralis Major
O: Medial half of clavicle, sternum, and cartilage of ribs 1-6
I: Crest of greater tubercle of humerus
N: Lateral and Medial Pectoral nerve: C5-T1
A: All fibers - Adduct the shoulder (glenohumeral joint), medially rotate the shoulder (G/H joint), Assist to elevate the thorax during forced inhalation (with arm fixed)
Upper fibers - Flex the shoulder (G/H joint), Horizontally adduct the shoulder (G/H joint)
Lower fibers - Extend the shoulder (G/H joint)
Teres Major
O: Inferior angle and lower 1/3 of lateral border of scapula
I: Crest of lesser tubercle of the humerus
N: Lower subscapular C5-C7
A: Extend the shoulder (glenohumeral joint), adduct the shoulder (G/H joint), medially rotate the shoulder
Subclavius
O: First rib and cartilage
I: Inferior surface of middle one-third of clavicle
N: Subclavian C5-C6
A: Depress the clavicle and draw it anteriorly, elevate the first rib (to assist during inhalation), stabilize the sternoclavicular joint
Pronator Quadratus
O: Medial, anterior surface of distal ulna
I: Lateral, anterior surface of distal radius
N: Anterior interosseous nerve (Median; C7-T1)
A: Pronates forearm