Unit 4: Upper Extremity Muscles (Shoulder and Upper Arm) Flashcards
Action:
-Unilaterally elevate the scapula
-Unilaterally, downwardly rotate the scapula
-Unilaterally, laterally flex the head and neck
-Unilaterally, rotate the head and neck to the same side
-Bilaterally extend the head and neck
Origin:
-Transverse processes of first through fourth cervical vertebrae
Insertion:
-Medial border of scapula, between superior angle and superior portion of spine of scapula
levator scapula
Action:
-Upper fibers bilaterally extend the head and neck
-Upper fibers unilaterally, laterally flex the head and neck to the same side
-Upper fibers unilaterally, rotate the head and neck to the opposite side
-Upper fibers unilaterally, elevate the scapula
-Upper fibers unilaterally, upwardly rotate the scapula
-Middle fibers adduct and stabilize the scapula
-Lower fibers depress and upwardly rotate the scapula
Origin:
-External occipital protuberance, medial portion of superior nuchal line of the occiput, ligamentous nuchal and spinous processes of C7-T12
Insertion:
-Lateral one-third of clavicle, acromion and spine of the scapula
trapezius
upper trapezius
middle trapezius
lower trapezius
Action:
-Depress the scapula
-Abduct the scapula
-Downwardly rotate the scapula
Origin:
-Third, fourth and fifth ribs
Insertion:
-Medial surface of coracoid process of the scapula
pectoralis minor
Action:
-Adduct the scapula
-Elevate the scapula
-Downwardly rotate the scapula
Origin:
-Spinous processes of T2-T5
Insertion:
-Medial border of the scapula between the spine of the scapula and inferior angle
rhomboid major
Action:
-Adduct the scapula
-Elevate the scapula
-Downwardly rotate the scapula
Origin:
-Spinous processes of C7-T1
Insertion:
-Upper portion of medial border of the scapula, across from spine of the scapula
rhomboid minor
Action:
-With the origin fixed, abduct the scapula
-With the origin fixed, upwardly rotate the scapula
-With the origin fixed, depress the scapula
-With the origin fixed, hold the medial border of the scapula against the rib cage
-With the scapula fixed, may act to elevate the thorax during forced inhalation
Origin:
-External surfaces of upper eight or nine ribs
Insertion:
-Anterior surface of medial border of the scapula
serratus anterior
Action:
-Depress the clavicle and draw it anteriorly
-Elevate first rib
-Stabilize the sternoclavicular joint
Origin:
-First rib and cartilage
Insertion:
-Inferior surface of middle one-third of clavicle
subclavius
Action:
-All fibers, adduct the shoulder
-All fibers, medially rotate the shoulder
-Upper fibers, flex the shoulder
-Upper fibers, horizontally adduct the shoulder
-Lower fibers, extend the shoulder
Origin:
-Medial half of clavicle, sternum and cartilage of first through sixth ribs
Insertion:
Crest of greater tubercle of humerus
pectoralis major
Action:
-All fibers, abduct the shoulder
-Anterior fibers, flex, medially rotate, and horizontally adduct the shoulder
-Posterior fibers, extend, laterally rotate, and horizontally abduct the shoulder
Origin:
-Lateral one-third of clavicle, acromion and spine of scapula
Insertion:
-Deltoid tuberosity
deltoid
anterior deltoid
middle deltoid
posterior deltoid
Includes:
-Supraspinatus
-Infraspinatus
-Teres minor
-Subscapularis
rotator cuff
Action:
-Abduct the shoulder
-Stabilize the head of humerus in glenoid cavity
Origin:
-Supraspinous fossa of the scapula
Insertion:
-Greater tubercle of the humerus
supraspinatus
Action:
-Laterally rotate shoulder
-Adduct the shoulder
-Stabilize the head of humerus in glenoid cavity
Origin:
-Infraspinous fossa of scapula
Insertion:
-Greater tubercle of the humerus
infraspinatus
Action:
-Laterally rotate the shoulder
-Adduct the shoulder
-Stabilize the head of humerus in glenoid cavity
Origin:
-Upper two-thirds of lateral border of the scapula
Insertion:
-Greater tubercle of the humerus
teres minor
Action:
-Medially rotate the shoulder
-Stabilize the head of humerus in glenoid cavity
Origin:
-Subscapular fossa of the scapula
Insertion:
-Lesser tubercle of the humerus
subscapularis
primary responsibility is to maintain shoulder joint stability
action of the rotator cuff
Action:
-Extend the shoulder
-Adduct the shoulder
-Medially rotate the shoulder
Origin:
-Inferior angle and lower one-third of lateral border of the scapula
Insertion:
-Crest of the lesser tubercle of the humerus
teres major
Action:
-Extend the shoulder
-Adduct the shoulder
-Medially rotate the shoulder
Origin:
-Inferior angle of scapula, spinous processes of last six thoracic vertebrae, last three or four ribs, thoracolumbar fascia and posterior iliac crest
Insertion:
-Intertubercular groove of the humerus
latissimus dorsi
Action:
-Flex the elbow
-Supinate the forearm
-Flex the shoulder
Origin:
-Short head, coracoid process of scapula
-Long head, supraglenoid tubercle of scapula
Insertion:
-Tuberosity of the radius and aponeurosis of the biceps brachii
biceps brachii
Action:
-Flex the shoulder
-Adduct the shoulder
Origin:
-Coracoid process of the scapula
Insertion:
-Medial surface of mid-humeral shaft
coracobrachialis
Action:
-All heads, extend the elbow
-Long head, extend and adduct the shoulder
Origin:
-Long head, infraglenoid tubercle of the scapula
-Lateral head, posterior surface of proximal half of the humerus
-Medial head, posterior surface of distal half of the humerus
Insertion:
-Olecranon process of the ulna
triceps brachii
-Supraspinatus (eccentric contraction)
-Infraspinatus (concentric contraction)
-Teres Minor (concentric contraction)
early and late cocking throwing motion
subscapularis (concentric contraction)
acceleration throwing motion
-Supraspinatus (concentric contraction)
-Infraspinatus (eccentric contraction)
-Teres Minor (eccentric contraction)
deceleration and follow-through throwing motion
