A&P practical #2 Flashcards
What are the 4 muscles of the thorax, shoulder, and trunk?
Pectoralis major, deltoid, latissimus dorsi, rectus abdominus
Pectoralis major: origin
clavicle and sternum and costal cartilages 2-6
Pectoralis major: insertion
greater tubercle of humerus
Pectoralis major: action
prime mover of arm flexion, adduction and medial rotation of arm, elevates rib cage during deep inspiration
Deltoid: origin
spine and acromion process of scapula, later 1/3 of clavicle
deltoid: insertion
deltoid tuberosity of humerus
deltoid: action
prime mover of arm abduction, synergist in flexion, extension of arm
Latissimus dorsi: origin
spines of T7-T12, ribs 8-12, iliac crest and thoracolumbar fascia
Latissimus dorsi: insertion
intertubercular groove of humerus
Latissimus dorsi: action
prime arm extensor, adduction and medial rotation at the shoulder, depresses shoulder
Rectus abdominus: origin
pubic symphysis, pubic crest
rectus abdominis: insertion
xiphoid process, costal cartilages of ribs 5-7
rectus abdominus: action
trunk flexion, compresses, abdominal viscera, expiration
What are the 4 rotator cuff muscles of the arm?
supraspinatus, infraspinatus, teres minor, subscapularis
supraspinatus: origin
supraspinous fossa
supraspinatus: insertion
greater tubercle of humerus
supraspinatus: action
shoulder abduction
Infraspinatus: origin
infraspinous fossa
infraspinatus: insertion
greater tubercle of humerus
infraspinatus: action
externally/ laterally rotates
teres minor: origin
lateral border of scapula
teres minor: insertion
greater tubercle of humerus
teres minor: action
externally/ laterally rotates
subscapularis: origin
subscapular fossa
subscapularis: insertion
lesser tubercle of humerus
subscapularis: action
internally/ medially rotates
What are the 4 muscles of the arm?
biceps brachii, triceps brachii, brachialis, brachioradialis
Biceps brachii: origin of long head
supraglenoid tubercle of scapula
biceps brachii: origin of short head
coracoid process of scapula
biceps brachii: insertion
radial tuberosity
biceps brachii: action
major forearm flexor, supinates forearm, weak flexor of arm
triceps brachii: origin of long head
infraglenoid tubercle
triceps brachii: origin of lateral head
posterior superior humerus
triceps brachii: origin of medial head
posterior inferior humerus
Triceps brachii: insertion
olecranon process of ulna
triceps brachii: action
extends forearm
brachialis: origin
distal anterior humerus
brachialis: insertion
ulnar tuberosity and coronoid process