All Muscles Term II Flashcards
Masseter
O- zygomatic arch of the temporal bone
I- angle, ramus, and coronoid process of the mandible
A- elevates/protracts the mandible at temporomandibular joint
Temporalis
O- temporal fossa
I- coronoid process and ramus of mandible
A- elevates/retracts the mandible at temporomandibular joint
Frontalis
O- galea aponeurotica
I- fascia and skin overlaying the frontal bone
A- draws the scalp posteriorly/anteriorly
Occipitalis
O- superior nuchal line of the occiput and mastoid area of the temporal bone
I- galea aponeurotica
A- draws the scalp posteriorly (anchor and retract galea aponeurotica)
Sternocleidomastoid
O: sternal head- anteromedial manumbium of the sternum
clavicular head- medial (one third of the) clavicle
I: mastoid process of the temporal bone and lateral superior nuchal line of the occipital bone
A: Unilaterally- laterally flexes the head and neck to the same side at the spinal joints, rotates the head and neck to the opposite side (contralaterally rotates) at the spinal joints
Bilaterally- flexes the head and neck at the spinal joints
Scalenes
O: as a group- transverse processes (TPs) of C2-C7
I: anterior & middle- first rib (posterior to clavicle)
posterior- second rib (at or above trapezius)
A: Unilaterally- with ribs fixed, laterally flexes the neck to the same side at the spinal joints, rotates the neck to the opposite side (contralaterally rotates) at the spinal joints
Bilaterally- flexes the neck at the spinal joints (anterior and middle scalenes (elevates the ribs during inhalation at the sternocostal and costospinal joints)
Splenius Capitis
O: inferior (one half) ligamentum nuchae and spinous processes (SPs) of C7-T4
I: mastoid process of the temporal bone and lateral (one third of the) superior nuchal lines of the occipital bone
A: Unilaterally- laterally flexes the head and neck to the same side as the spinal joints, rotates the head and neck to the same side (ipsilaterally rotates) at the spinal joints
Bilaterally- extends the head and neck at the spinal joints
Splenius Cervicis
O: spinous processes (SPs) of T3-T6
I: transverse processes (TPs) of C1-C3
A: Unilaterally- laterally flexes the neck to the same side at the spinal joints, rotates the neck to the same side (ipsilaterally rotates) at the spinal joints
Bilaterally- extends the neck at the spinal joints
Diaphragm
O: internal surface of ribs 7-12 and their costal cartilage, internal surface of the xiphoid process of the sternum, and anterior vertebral bodies of L1-L3
I: central tendon (dome) of the diaphragm
A: expands the thoracic cavity when abdominal breathing
External Intercostals
O: inferior boarder of one rib
I: superior boarder of the rib directly inferior
A: elevates the ribs at the sternocostal and costospinal joints (to assist with inhalation)
Internal Intercostals
O: superior boarder of one rib (and its costal cartilage)
I: inferior boarder of the rib (and its costal cartilage) directly superior
A: depresses ribs at the sternocostal and costospinal joints (to assist with exhalation)
Serratus Posterior Superior
O: inferior ligamentum nuchae and spinous processes (SPs) of C7-T3
I: superior external surfaces of ribs 2-5
A: elevate ribs 2-5 (during inhalation) at the sternocostal and costospinal joints
Serratus Posterior Inferior
O: spinous processes of T11-L3
I: inferior external surfaces of ribs 9-12
A: depress ribs 9-12 (in exhalation) at the sternocostal and costospinal joints
Upper Fibers of Trapezius
O: external occipital protuberance, superomedial (one third of the) nuchal line of the occiput and ligamentum nuchae
I: posterolateral (one third of the) clavicle
A: elevates the scapula at the scapulothoracic joint
upwardly rotates the scapula at the scapulothoracic joint
Middle Fibers of Trapezius
O: spinous processes (SPs) of C7-T3
I: acromion process and superior border of the scapular spine
A: adducts (retracts) the scapula at the scapulothoracic joint
Lower Fibers of Trapezius
O: spinous processes (SPs) of T4-T12
I: tubercle at the root of the spine of the scapula
A: depress the scapula at the scapulothoracic joint
upwardly rotates the scapula at the scapulothoracic joint
adducts (retracts) the scapula at the scapulothoracic joint
Rhomboids
O: spinous processes (SPs) of C7-T5
I: medial border of the scapula from the root of the spine to the inferior angle
A: adducts (retracts) the scapula at the scapulothoracic joint
elevates the scapula at the scapulothoracic joint
downwardly rotates the scapula at the scapulothoracic joint
Levator Scapula
O: transverse processes (TPs) of C1-C4
I: medial border of the scapula from the superior angle to the root of the spine of the scapula
A: elevates the scapula at the scapulothoracic joint
downwardly rotates the scapula at the scapulothoracic joint
Serratus Anterior
O: external surfaces of anterolateral ribs 1-9
I: anterior surface of the medial border of the scapula
A: abducts (protracts) the scapula at the scapulothoracic joint
upwardly rotates the scapula at the scapulothoracic joint
depress the scapula at the scapulothoracic joint
Pectoralis Minor
O: ribs 3-5
I: medial aspect of the coracoid process of the scapula
A: abducts (protracts) the scapula at the scapulothoracic joint
depresses the scapula at the scapulothoracic joint
downwardly rotates the scapula at the scapulothoracic joint
Deltoid
O: Anterior fibers- lateral (one third of the) clavicle
Middle fibers- lateral acromion process of the scapula
Posterior fibers- spine of the scapula
I: deltoid tuberosity of the humerus
A: All fibers- abduct the shoulder at the glenohumeral joint
Anterior fibers- flex the shoulder at the glenohumeral joint
internally rotate the shoulder at the glenohumeral joint
horizontally adduct the shoulder at the glenohumeral joint
Posterior fibers- extend the shoulder at the glenohumeral joint
externally rotate the shoulder at the glenohumeral joint
horizontally abduct the shoulder at the glenohumeral joint
Coracobrachialis
O: coracoid process of the scapula
I: medial surface of the mid-humeral shaft
A: flexes the shoulder at the glenohumeral joint
adducts the shoulder at the glenohumeral joint
horizontally adducts the shoulder at the glenohumeral joint
Pectoralis Major
O: clavicular fibers- anteromedial (one half of the) clavicle Middle
sternal fibers- sternum and costal cartilage of ribs 1-6
I: crest of the greater tubercle of the humerus
A: All fibers- adduct the shoulder at the glenohumeral joint
internally rotate the shoulder at the glenohumeral joint
Clavicular fibers- flex the shoulder at the glenohumeral joint
horizontally adduct the shoulder at the glenohumeral joint
Sternal fibers- extend the shoulder at the glenohumeral joint
Latissimus dorsi
O: spinous processes (SPs) of T7-L5, posterior sacrum, posterior iliac crest and posterior ribs 10-12 all via the thoracolumbar fascia
I: intertubercular (bicipital) groove (just on the inside of the lesser tubercle) of the humerus
A: internally rotates the shoulder at the glenohumeral joint
adducts the shoulder at the glenohumeral joint
extends the shoulder at the glenohumeral joint
Teres Major
O: inferior angle and inferior (one third of the) lateral border of the scapula
I: crest of the lesser tubercle of the humerus
A: internally rotates the shoulder at the glenohumeral joint
adducts the shoulder at the glenohumeral joint
extends the shoulder at the glenohumeral joint
Supraspinatus
O: supraspinous fossa of the scapula
I: superior greater tubercle of the humerus
A: abducts the shoulder at the glenohumeral joint
stabilizes the shoulder at the glenohumeral joint
Infraspinatus
O: infraspinous fossa of the scapula
I: posterior greater tubercle of the humerus
A: externally rotates the shoulder at glenohumeral joint
adducts the shoulder at the glenohumeral joint
stabilizes the shoulder at the glenohumeral joint
Teres Minor
O: superior (two thirds of the) lateral border of the scapula
I: posterior greater tubercle of the humerus
A: externally rotates the shoulder at the glenohumeral joint
adducts the shoulder at the glenohumeral joint
stabilizes the shoulder at the glenohumeral joint
Subscapularis
O: subscapular fossa of the scapula
I: lesser tubercle of the humerus
A: internally rotates the shoulder at the glenohumeral joint
stabilizes the shoulder at the glenohumeral joint
Biceps Brachii
O: long head- supraglenoid tubercle of the scapula
short head- coracoid process of the scapula
I: tuberosity of the radius and bicipital aponeurosis
A: flexes the elbow at the humeroulnar joint
supinates the forearm at the radioulnar joints
flexes the shoulder at the glenohumeral joint
Triceps Brachii
O: long head- infraglenoid tubercle of the scapula
lateral head- proximal (one third of the) posterior shaft of the humerus
medial head- distal (two thirds of the) posterior shaft of the humerus medial head
I: olecranon process of the ulna
A: all heads- extends the elbow at the glenohumeral joint
long head- extends the shoulder at the glenohumeral joint
adducts the shoulder at the glenohumeral joint
horizontally abducts the shoulder at the glenohumeral joint
Brachialis
O: distal (half of the) anterior shaft of the humerus
I: tuberosity and coronoid process of the ulna
A: flexes the shoulder at the humeroulnar joint
Brachioradialis
O: proximal (two thirds of the) lateral supracondylar ridge of the humerus
I: lateral side of the styloid process of the radius
A: flexes the elbow at the humeroulnar joint
supinates* the forearm at the radioulnar joints
pronates* the forearm at the radioulnar joints
*Supination from pronation to neutral of the forearm and pronation from supination to neural of the forearm
Pronator Teres
O: medial epicondyle of the humerus and coronoid process of the ulna
I: middle (third) of lateral surface of the radius
A: pronates the forearm at the radioulnar joints
flexes the elbow at the humeroulnar joint
Supinator
O: lateral epicondyle of the humerus, supinator crest of the ulna and the proximal ulna*
I: anterior, lateral surface of proximal (one third of the) radial shaft
A: supinates the forearm at the radioulnar joints
*Supinator comes posteriorly off the ulna and wraps around the lateral radius to its insertion
Flexors of the Wrist (as a group)
O: medial epicondyle of the humerus
Muscle group general location: proximal, anteromedial forearm
A: flexes the wrist at the radiocarpal joint (and flexes the elbow at the humeroulnar joint)
Extensors of the Wrist (as a group)
O: lateral epicondyle of the humerus
Muscle group general location: proximal, posterolateral forearm
A: extends the wrist at the radiocarpal joint (and extends the elbow at the humeroulnar joint)
