Muscles 1 Flashcards
Muscles Week 1
Pectoralis minor Origin
Ribs 3-5 and overlying fascia
Serratus anterior Origin
All or nearly all ribs
Trapezius Origin
External occipital protuberance, medial one-third of superior nuchal line, nuchal ligament, lateral one-third of clavicle anterior rami of C3-C4 spinous processes of vertebrae C7-T3 or T4
Levator scapulae Origin
Transverse processes of vertebrae C1-C4
Rhomboid major Origin
Spinous processes of vertebrae T2-T5
Rhomboid minor Origin
Spinous processes of vertebrae C7-T1, nuchal ligament
Pectoralis major Origin
Medial half of clavicle, costal cartilages 1-7, aponeurosis of external oblique
Latissimus dorsi Origin
Vertebrae T7-L5, lower three or four ribs, iliac crest, thoracolumbar fascia
Deltoid Origin
Acromion and spine of scapula; clavicle
Supraspinatus Origin
Supraspinous fossa of scapula
Infraspinatus Origin
Infraspinous fossa of scapula
Teres major Origin
Inferior angle of scapula
Teres minor Origin
Lateral border and adjacent posterior surface of scapula
Subscapularis Origin
Subscapular fossa of scapula
Coracobrachialis Origin
Coracoid process
Biceps brachii, short head Origin
coracoid process
Biceps brachii, long head Origin
superior margin of glenoid cavity
Brachialis Origin
Anterior surface of distal half of humerus
Brachioradialis Origin
Lateral supracondylar ridge of humerus
Triceps brachii, lateral head Origin
posterior surface of proximal end of humerus
Triceps brachii, long head Origin
inferior margin of glenoid cavity and joint capsule
Triceps brachii, medial head Origin
posterior surface of entire humeral shaft
Anconeus Origin
Lateral epicondyle of humerus
Pronator quadratus Origin
Anterior surface of distal ulna
Pronator teres Origin
Humeral shaft near medial epicondyle; coronoid process of ulna
Supinator Origin
Lateral epicondyle of humerus; supinator crest and fossa of ulna just distal to radial notch; anular and radial collateral ligaments of elbow
Flexor carpi radialis Origin
Medial epicondyle of humerus
Flexor carpi ulnaris Origin
Medial epicondyle of humerus; medial margin of olecranon; posterior surface of ulna
Palmaris longus Origin
Medial epicondyle of humerus
Extensor carpi radialis longus Origin
Lateral supracondylar ridge of humerus
Extensor carpi radialis brevis Origin
Lateral epicondyle of humerus
Extensor carpi ulnaris Origin
Lateral epicondyle of humerus; posterior surface of ulnar shaft
Extensor digitorum Origin
Lateral epicondyle of humerus
Rectus abdominis Origin
Pubic symphysis and superior margin of pubis
Erector Spinae Origin
Nuchal ligament, ribs 3-12, thoracic and lumbar vertebrae, median and lateral sacral crests, thoracolumbar fascia
Semispinalis thoracis Origin
Vertebrae T6-T10
Multifidus Origin
Vertebrae C4-L5, posterior superior iliac spine, sacrum, aponeurosis of erector spinae
Quadratus lumborum Origin
Iliac crest, iliolumbar ligament
External oblique Origin
Ribs 5-12
Internal oblique Origin
Inguinal ligament, iliac crest, and thoracolumbar fascia
Transverse abdominis Origin
Inguinal ligament, iliac crest, thoracolumbar fascia, costal cartilages 7-12
External intercostals Origin
Inferior margins of ribs 1-11
Internal intercostals Origin
Superior margins and costal cartilages of ribs 2-12; margin of sternum
Pectoralis minor Insertion
Coracoid process of scapula
Serratus anterior Insertion
Medial border of scapula
Trapezius Insertion
Acromion and spine of scapula, lateral one-third of clavicle
Levator scapulae Insertion
Superior angle to medial border of scapula
Rhomboid major Insertion
Medial border of scapula
Rhomboid minor Insertion
Medial border of scapula
Pectoralis major Insertion
Lateral lip of intertubercular sulcus of humerus
Latissimus dorsi Insertion
Floor of intertubercular sulcus of humerus
Deltoid Insertion
Deltoid tuberosity of humerus
Supraspinatus Insertion
Greater tubercle of humerus
Infraspinatus Insertion
Greater tubercle of humerus
Teres major Insertion
Medial lip of intertubercular sulcus of humerus
Teres minor Insertion
Greater tubercle of humerus; posterior surface of joint capsule
Subscapularis Insertion
Lesser tubercle of humerus, anterior surface of joint capsule
Coracobrachialis Insertion
Medial aspect of humeral shaft
Biceps brachii, short head Insertion
Tuberosity of radius, fascia of forearm
Biceps brachii, long head Insertion
Tuberosity of radius, fascia of forearm
Brachialis Insertion
Coronoid process and tuberosity of ulna
Brachioradialis Insertion
Lateral surface of radius near styloid process
Triceps brachii, lateral head Insertion
Olecranon, fascia of forearm
Triceps brachii, long head Insertion
Olecranon, fascia of forearm
Triceps brachii, medial head Insertion
Olecranon, fascia of forearm
Anconeus Insertion
Olecranon and posterior surface of ulna
Pronator quadratus Insertion
Anterior surface of distal radius
Pronator teres Insertion
Lateral surface of radial shaft
Supinator Insertion
Proximal one-third of radius
Flexor carpi radialis Insertion
Base of metacarpals II-III
Flexor carpi ulnaris Insertion
Pisiform, hamate, metacarpal V
Palmaris longus Insertion
Flexor retinaculum, palmar aponeurosis
Extensor carpi radialis longus Insertion
Base of metacarpal II
Extensor carpi radialis brevis Insertion
Base of metacarpal III
Extensor carpi ulnaris Insertion
Base of metacarpal V
Extensor digitorum Insertion
Dorsal surfaces of phalanges II-V
Rectus abdominis Insertion
Xiphoid process, costal cartilages 5-7
Erector Spinae Insertion
Mastoid process, cervical and thoracic vertebrae, and all ribs
Semispinalis thoracis Insertion
Vertebrae C6-T4
Multifidus Insertion
Laminae and spinous processes of vertebrae superior to origins
Quadratus lumborum Insertion
Rib 12 and vertebrae L1-L4
External oblique Insertion
Anterior half of iliac crest, pubic symphysis, and superior margin of pubis
Internal oblique Insertion
Ribs 10-12, costal cartilages 7-10, pubis
Transverse abdominis Insertion
Linea alba, pubis, aponeurosis of internal oblique
External intercostals Insertion
Superior margin of next lower rib
Internal intercostals Insertion
Inferior margin of next higher rib
Pectoralis minor Action
With serratus anterior, draws scapula laterally and forward around chest wall; with other muscles, rotates scapula and depresses apex of shoulder, as in reaching down to pick up a suitcase
Serratus anterior Action
With pectoralis minor, draws scapula laterally and forward around chest wall; protracts scapula, and is the prime mover in all forward-reaching and pushing actions; aids in rotating scapula to elevate apex of shoulder; fixes scapula during abduction of arm
Trapezius Action
Stabilizes scapula and shoulder during arm movements; elevates and depresses apex of shoulder; acts with other muscles to rotate and retract scapula
Levator scapulae Action
Elevates scapula if cervical vertebrae are fixed; flexes neck laterally if scapula is fixed; retracts scapula and braces shoulder; rotates scapula and depresses apex of shoulder
Rhomboid major Action
Retracts scapula and braces shoulder; fixes scapula during arm movements
Rhomboid minor Action
Retracts scapula and braces shoulder; fixes scapula during arm movements
Pectoralis major Action
Flexes, adducts, and medially rotates humerus, as in climbing or hugging. Aids in deep inspiration.
Latissimus dorsi Action
Adducts and medially rotates humerus; extends the shoulder joint as in pulling on the oars of a rowboat; produces backward swing of arm in such actions as walking and bowling; with hands grasping overhead objects, pulls body forward and upward, as in climbing; aids in deep inspiration, sudden expiration such as sneezing and coughing, and prolonged forceful expiration as in singing or blowing a sustained note on a wind instrument
Deltoid Action
Anterior fibers flex and medially rotate arm; lateral fibers abduct arm; posterior fibers extend and laterally rotate arm; involved in arm swinging during such actions as walking or bowling, and in adjustment of hand height for various manual tasks
Supraspinatus Action
Aids deltoid in abduction of arm; resists downward slippage of humeral head when arm is relaxed or when carrying weight
Infraspinatus Action
Modulates action of deltoid, preventing humeral head from sliding upward; rotates humerus laterally
Teres major Action
Extends and medially rotates humerus; contributes to arm swinging
Teres minor Action
Modulates action of deltoid, preventing humeral head from sliding upward as arm is abducted; rotates humerus laterally
Subscapularis Action
Modulates action of deltoid, preventing humeral head from sliding upward as arm is abducted; rotates
Coracobrachialis Action
Flexes and medially rotates arm; resists deviation of arm from frontal plane during abduction
Biceps brachii, short head Action
Rapid or forceful supination of forearm; synergist in elbow flexion; slight shoulder flexion; tendon of long head stabilizes shoulder by holding humeral head against glenoid cavity
Biceps brachii, long head Action
Rapid or forceful supination of forearm; synergist in elbow flexion; slight shoulder flexion; tendon of long head stabilizes shoulder by holding humeral head against glenoid cavity
Brachialis Action
Prime mover of elbow flexion
Brachioradialis Action
Flexes elbow
Triceps brachii, lateral head Action
Extends elbow
Triceps brachii, long head Action
Extends elbow; long head extends and adducts humerus
Triceps brachii, medial head Action
Extends elbow
Anconeus Action
Extends elbow; may help to control ulnar movement during pronation
Pronator quadratus Action
Prime mover of forearm pronation; also resists separation of radius and ulna when force is applied to forearm through wrist, as in doing push-ups
Pronator teres Action
Assists pronator quadratus in pronation, but only in rapid or forceful action; weakly flexes elbow
Supinator Action
Supinates forearm
Flexor carpi radialis Action
Flexes wrist anteriorly; aids in radial flexion of wrist
Flexor carpi ulnaris Action
Flexes wrist anteriorly; aids in ulnar flexion of wrist
Palmaris longus Action
Anchors skin and fascia of palmar region; resists shearing forces when stress is applied to skin by such actions as climbing and tool use.
Extensor carpi radialis longus Action
Extends wrist; aids in radial flexion of wrist
Extensor carpi radialis brevis Action
Extends wrist; aids in radial flexion of wrist
Extensor carpi ulnaris Action
Extends and fixes wrist when fist is clenched or hand grips an object; aids in ulnar flexion of wrist
Extensor digitorum Action
Extends wrist, metacarpophalangeal, and interphalangeal joints; tends to spread digits apart when extending metacarpophalangeal joints
Rectus abdominis Action
Flexes lumbar region of vertebral column, producing forward bending at the waist
Erector Spinae Action
Extension and lateral flexion of vertebral column; the longissimus capitis also produces ipsilateral rotation of the head.
Semispinalis thoracis Action
Extension and contralateral rotation of vertebral column
Multifidus Action
Stabilization of adjacent vertebrae, maintenance of posture, control of vertebral movement when erector spinae acts on vertebral column
Quadratus lumborum Action
Aids respiration by fixing rib 12 and stabilizing inferior attachments of diaphragm. Unilateral contraction causes ipsilateral flexion of lumbar vertebral column; bilateral contraction extends lumbar vertebral column.
External oblique Action
Supports abdominal viscera against pull of gravity; stabilizes vertebral column during heavy lifting; maintains posture; compresses abdominal organs, thus aiding in forceful expiration of contents during childbirth, urination, defecation, and vomiting; unilateral contraction causes contralateral rotation of waist
Internal oblique Action
Supports abdominal viscera against pull of gravity; stabilizes vertebral column during heavy lifting; maintains posture; compresses abdominal organs, thus aiding in forceful expiration of contents during childbirth, urination, defecation, and vomiting; unilateral contraction causes ipsilateral rotation of waist
Transverse abdominis Action
Compresses abdominal contents, with same effects as external oblique, but does not contribute to movements of vertebral column
External intercostals Action
When scalenes fix rib 1, external intercostals elevate and protract ribs 2-12, expanding the thoracic cavity and creating a partial vacuum causing inflow of air; exercise a braking action during expiration so that expiration is not overly abrupt
Internal intercostals Action
In inspiration, the intercartilaginous part aids in elevating the ribs and expanding the thoracic cavity; in expiration, the interosseous part depresses and retracts the ribs, compressing the thoracic cavity and expelling air; the latter occurs only only in forceful expiration, not in relaxed breathing
