Muscle OIA's Flashcards
Pectoralis Major
O: medial clavicle, sternum, and costal cartilages of the ribs
I: inter-tubercular groove-lateral lip
A: flexes the shoulder, adducts and medially rotates the humerus
Pectoralis Minor
O: ribs 3-5
I: coracoid process of the scapula
A: pulls scapula anteriorly and inferiorly / if scapula is fixed, elevates ribs
Trapezius
O: Superior nuchal line, external occipital protuberance, ligamentium niche, spinous processes of C7 and all thoracic vertebrae
I: lateral clavicle, acrimonious process and spine of the vertebrae
A: adducts scapula, elevates and rotates shoulder upward / if scapula is fixed, draws the head backward (hyperextends)
Latissimus Dorsi
O: lower thoracic and lumbar vertebrae and lumbodorsal fascia (thoracolumbar fascia / aponeurosis)
I: Inter-tubercular groove
A: extends the shoulder, adducts and medially rotates the humerus
Serratus Anterior
O: anterior superior surface of the first 8 or 9 ribs
I: anterior surface of vertebral border of scapula
A: holds scapula to chest wall, rotates scapula so shoulder moves upward
Rhomboids Major
O: spinous process of C7 and T1 vertebrae
I: vertebral border of scapula at base of spine
A: adducts scapula, rotates the scapula so shoulder moves downward
Deltoid
O: lateral clavicle, acrimonion process and sine of scapula
I: deltoid tuberosity
A: flexes and extends shoulder; abducts humerus
Rotator Cuff Mnemonic
SITTS
- Supraspinatus
- Infraspinatus
- Teres Minor
- Teres Major
- Subscapularis
Supraspinatus
O: supraspinous fossa
I: greater tubercle of the humerus
A: abducts the humerus
Infraspinatus
O: infraspinous fossa
I: greater tubercle of the humerus
A: laterally rotates the humerus
Teres Minor
O: axillary border of scapula above teres major
I: greater tubercle of the humerus
A: laterally rotates the humerus
Teres Major
O: inferior axillary border of scapula
I: intertubercular groove (medial lip)
A: extends the shoulder, adducts an medially rotates humerus
Subscapularis
O: subscapular fossa
I: lesser tubercle of humerus
A: adducts and medially rotates the humerus
Triceps
(Three Heads)
O: below the glenoid fossa (long head) and posterior shaft of the humerus (other 2 heads)
I: olecranon process of the ulna
A: extends shoulder and elbow
Biceps Brachii
(Two Heads)
O: coracoid process (short head) and above the glenoid fossa (long head)
I: radial tuberosity
A: extends shoulder and elbow, supinates forearm and hand
Coracobrachialis
O: coracoid process of the scapula
I: proximal medial humerus
A: flexes shoulder and adducts the humerus
Brachialis
O: distal anterior surface of the humerus
I: coronoid process of the ulna
A: flexes elbow
Brahioradialis
O: ridges superior to the lateral epicondyle of the humerus
I: radial styloid process
A: flexes elbow
Pronator Teres
O: medial epicondyle of the humerus
I: lateral surface of the mid shaft of the radius (distal of the insertion of the supinator
A: pronates forearm and hand, flexes elbow
Flexor Carpi Radialis
O: medial epicondyle of the humerus
I: base of the 2nd and 3rd metacarpals - anterior aspect
A: flexes elbow, flexes and abducts wrist
Palmaris Longus
O: medial epicondyle of the humerus
I: palmar aponeurosis
A: tenses palmar aponeurosis, flexes elbow and wrist
Flexor Digitorum Superficialis
O: medial epicondyle of the humerus, coronoid process of ulna and proximal radius
I: medial phalanges of digits 2-5
A: flexes all joints, except distal, of all fingers; flexes wrist and elbow
Flexor Carpi Ulnaris
O: medial epicondyle of the humerus
I: base of 5th metacarpal - anterior aspect, pisiform, hamate
A: flexes elbow, flexes and adducts wrist
Flexor Digitorum Profundus
O: anterior medial surface of the proximal ulna
I: distal phalanges of digits 2-5
A: flexes all joints (including distal) of all fingers, flexes wrist
Pronator Quadratus
O: distal anterior ulna
I: distal anterior radius
A: pronates forearm and hand
Flexor Pollicis Longus
A: flexes pollex
Extensor Carpi Radialis Longus
O: ridge superior to the lateral epicondyle of the humerus
I: base of second metacarpal - posterior aspect
A: extends elbow, extends and abducts wrist
Extensor Carpi Radialis Brevis
O: lateral epicondyle of the humerus
I: base of the 3rd metacarpal
A: extends elbow, extends and abducts wrist
Extensor Digitorum
O: lateral epicondyle of the humerus
I: posterior surfaces of the phalanges of digits 2-5
A: extends elbow, extends and abducts wrist
Extensor Digitorum
O: lateral epicondyle of the humerus
I: base of the 5th metacarpal - posterior aspect
A: extends elbow, extends and adducts wrist
Extensor Indicus
A: extends the second digit
Extensor Pollicis Longus
A: extends pollex, abducts wrist
Extensor Pollicis Brevis
A: extends pollex, abducts wrist
Abductor Pollicis Longus
A: abducts pollex
Supinator
O: proximal posterior ulna, lateral epicondyle of the humerus
I: lateral surface of the radius distal to the radial tuberosity (proximal to pronator teres)
A: supinates forearm and hand
Palmar Interossei
A: adducts fingers
Dorsal Interossei
A: abducts the fingers
Lumbricals
A: flex the metacarpophalangeal (MCP) joints, extend the interphalangeal joints
(Numbered 1-4 starting with the index finger)
