Anatomy Muscles - Exam1 Flashcards
Upper Trapezius
Proximal: external occipital protuberance, medial 1/3 of superior nuchal line, ligamentum nuchae, spinous process C7
Distal: lateral 1/3 of clavicle
Innervation: accessory nerve (CN XI)
Action: elevation of scapula, capital extension, cervical extension, rotation of head to opposite side, (with lower trap) upward rotation of the scapula
Middle Trapezius
P: spinous process T1-T5
D: medial margin of acromion, spine of scapula
N: accessory nerve (CN XI)
A: scapular adduction
Lower Trapezious
P: spinous process T6-T12
D: spine of scapula tubercle
N: C3, C4 with contributions from accessory nerve
A: scapular adduction, scapular upper rotation, scapular depression
Rhomboid Minor
P: ligamentum nuchae, sp of C7 and T1
D: root of scapular spine
N: dorsal scapular nerve (C5)
A: scapular adduction, scapular downward rotation, scapular elevation
Rhomboid Major
P: sp of T2-T5
D: medial border of scapula from spine to inferior angle
N: dorsal scapular nerve (C5)
A: scapular adduction, downward rotation, scapular elevation
Levator Scapulae
P: posterior tubercles of transverse precesses if C1-C4
D: medial border of scapula superior to spine of scapula
N: dorsal scapular nerve (C5), C3, C4
A: Scapular elevation, adduction, and downward rotation; Cervical rotation to same side, cervical bending to same side; assists in cervical extension (bilateral)
Deltoid Anterior
P: later 1/3 of clavicle
D: deltoid tuberosity of humerus
N: axillary nerve (C5, C6)
A: flexes & medially rotates arm, horizontal adduction, abduction of arm
Deltoid Middle
P: acromion
D: deltoid tuberosity of humerus
N: axillary nerve (C5, C6)
A: abducts arm
Deltoid Posterior
P: scapular spine
D: deltoid tuberosity of humerus
N: axillary nerve (C5, C6)
A: extends & laterally rotates arm, horizontal abduction, abduction of arm
Supraspinatus
P: supraspinous fossa of scapula
D: superior facet of greater tubercle of humerus
N: suprascapular nerve (C5, C6)
A: maintains humeral head in glenoid fossa, abduction of shoulder (initiates abduction)
Infraspinatus
P: infraspinous fossa of scapula
D: middle facet of greater tubercle of humerus
N: suprascapular nerve (C5, C6)
A: maintains humeral head in glenoid fossa, laterally rotates arm
Teres Minor
P: middle part of later border of scapula
D: inferior facet of greater tubercle of humerus
N: axillary nerve (C5, C6)
A: maintains humeral head in glenoid fossa, laterally rotates arm, assists in adduction
Pectoralis Major
P: clavicular head: anterior surface of medial half of claviclesternocostal head: sternum (anterior surface to rib 6), Ribs 2-7 (costal cartilage), aponeurosis of external oblique
D: lateral lip of intertubercular groove of humerus (crest of greater tubercle)
I: upper (clavicular) head: lateral pectoral nerve (C5-C7); lower (sternocostal) head: medial and lateral pectoral nerves (C6-T1)
A: whole muscle: adducts and medially rotates humerus, elevation of sternum in forced inspiration (with UE fixed); clavicular (upper) head: horizontal shoulder adduction, flexion and medial rotation; sternocostal (lower) head: horizontal shoulder adduction (obliquely toward opposite hip), shoulder extension
Pectoralis Minor
P: 3rd-5th ribs near their costal cartilages
D: medial border and superior surface of coracoid process
I: medial and lateral pectoral nerves (C5-T1)
A: scapular protraction/abduction (“anterior tilt”), elevation of ribs in forced inspiration with scapula fixed by levator scapulae
Subclavius
P: junction of 1st rib and its costal cartilage
D: inferior surface of middle 1/3 of clavicle
I: nerve to subclavius (C5-C6)
A: depresses and moves clavicle forward (provides protection for nerves, veins, and arteries); Assists shoulder depression
Subscapularis
P: subscapular fossa
D: lesser tubercle of humerus
I: upper & lower subscapular nerve (C5, 6)
A: medially rotates arm, maintains humeral head in glenoid fossa
Latissimus Dorsi
P: Thoracolumbar fascia (sp of T6-T12, sp of lumbar and sacral), ribs 9-12, iliac crest
D: floor of inter-tubercular groove
I: thoracodorsal nerve (C6-C8)
A: extends, adducts, medially rotates humerus; with insertion fixed, will hyperextend spine and anteriorly tilt pelvis
Teres Major
P: posterior surface of inferior angle of scapula
D: medial lip of intertubercular groove of humerus
I: lower subscapular nerve (C5, C6)
A: medially rotates arm, adducts arm, extends arm from a flexed position
Biceps Brachii
P: short head: tip of coracoid process; long head: supraglendoid tubercle of scapula, through capsule of glenohumeral joint and labrum
D: tuberosity of radius and fascia of forearm via bicipital aponeurosis
I: musculocutaneous nerve (C5, C6)
A: shoulder flexion, elbow flexion, forearm supination, stabilization of GH joint
Brachialis
P: distal 1/2 anterior surface of humerus
D: ulnar tuberosity and coronoid process
I: musculocutaneous nerve (C5, C6)
A: elbow flexion
Coracobrachialis
P: tip of coracoid process
D: middle 1/3 of medial surface of humerus
I: musculocutaneous nerve (C5-C7)
A: flexion and adduction of arm
Triceps Brachii (long head)
P: infraglenoid tubercle of scapula
D: proximal end of olecranon of ulna, capsule of elbow joint & antebrachial fascia
I: radial nerve (C6-C8)
A: extension of elbow, assist extension and adduction of shoulder
Triceps Brachii (lateral head)
P: posterior surface of humerus, superior to radial groove and lateral intermuscular septum
D: proximal end of olecranon of ulna, capsule of elbow joint & antebrachial fascia
I: radial nerve (C6-C8)
A: extension of elbow
Triceps Brachii (medial head)
P: posterior surface of humerus inferior to radial groove, medial and lateral intermuscular septa
D: proximal end of olecranon of ulna, capsule of elbow joint & antebrachial fascia
I: radial nerve (C6-C8)
A: extension of elbow
Brachioradialis
P: proximal 2/3 of lateral supracondylar ridge of humerus & lateral intermuscular septum
D: lateral surface of distal end of radius proximal to styloid process
I: radial nerve (C5, C6)
A: elbow flexion - strongest in the midprone position
Aconeus
P: lateral epicondyle of humerus and capsule of elbow joint
D: lateral surface of olecranon and superior part of posterior surface of ulna
I: radial nerve (C6-C8)
A: elbow extension (weak)
Pronator Teres
P: humeral head: shaft proximal to medial epicondyle and common flexor tendon; ulnar head: coronoid process
D: lateral surface of middle shaft of radius
I: median nerve (C6-C7)
A: pronation of forearm, assists with elbow flexion
Pronator Quadratus
P: distal 1/4 of anterior surface of ulna
D: distal 1/4 of anterior surface of radius
I: median nerve (anterior interosseous n.) (C7-C8)
A: pronation of forearm
Supinator
P: lateral epicondyle of humerus, radial collateral & annular ligament, supinator crest of ulna
D: lateral surface of proximal 1/3 of radius, tuberosity & oblique line of radius
I: radial nerve (C6, C7)
A: supination of forearm
Extensor Carpi Radialis Longus
P: lateral supracondylar ridge of humerus, common extensor tendon, lateral intermuscular septum
D: dorsal aspect of base of 2nd metacarpal on radial side
I: radial nerve (C6, C7)
A: wrist extension, radial (abduction) deviation, assist elbow flexion
Extensor Carpi Radialis Brevis
P: lateral epicondyle of humerus via common extensor tendon, radial collateral ligament of elbow joint
D: dorsal aspect of base of 3rd metacarpal on radial side - some slips sent to 2nd metacarpal bone
I: radial nerve (posterior interosseous branch) (C7, C8)
A: extend wrist & assist with radial deviation
Extensor Carpi Ulnaris
P: lateral epicondyle of humerus via common extensor tendon, posterior border of ulna by an aponeurosis shared by FCU & FDP
D: tubercle on dorsal aspect of base of 5th metacarpal
I: radial nerve (posterior interosseous branch)
A: extend & ulnar (adduction) deviation of wrist
Flexor Carpi Radialis
P: medial epicondyle of humerus by common flexor tendon
D: bases of 2nd & 3rd metacarpals
I: median nerve (C6-C7)
A: flexion and radial deviation (abduction) of wrist, assists elbow flexion and forearm pronation
Palmaris Longus
P: medial epicondyle of humerus by common flexor tendon
D: flexor retinaculum & palmar aponeurosis
I: median nerve (C7-C8)
A: tenses palmar fascia, wrist flexion