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Gross Anatomy > Unit 1 > Flashcards

Unit 1 Flashcards

1
Q

Trapezius

A

Origin: medial third of superior nuchal line, external occipital protuberance, nuchal ligament, spinous processes of C7-T12

Insertion: Lateral third of clavicle, acromion, and spine of scapula

Innervation: spinal accessory nerve (CN XI: motor fibers) and C3, C4 spinal nerves (pain and proprioceptive fibers)

Action: descending fibers-elevates scapula
Ascending fibers-depresses scapula
Ascending and descending fibers both rotate glenoid cavity superiorly
Middle fibers-retracts scapula

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2
Q

Latissimus Dorsi

A

Origin: spinous processes of inferior six thoracic vertebrae, thoracolumbar fascia, iliac crest, inferior three or four ribs

Insertion: floor of intertubercular sulcus (groove) of humerus

Innervation: thoracodorsal nerve (C6, C7, C8)

Action: Extends, adducts, and medially rotates shoulder joint; raises body towards arms during climbing

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3
Q

Levator Scapulae

A

Origin: posterior tubercles of transverse processes of C1-C4 vertebrae

Insertion: medial border of scapula superior to root of spine

Innervation: dorsal scapular (C5) and cervical (C3, C4) spinal nerves

Action: elevates scapula and tilts its glenoid cavity inferiorly by rotating scapula

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4
Q

Rhomboid Minor

A

Origin: nuchal ligament, spinous processes of C7 and T1 vertebrae

Insertion: triangular area at medial end of scapular spine

Innervation: dorsal scapular nerve (C4, C5)

Action: retract scapula and rotate it to depress glenoid cavity; fix scapula to thoracic wall

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5
Q

Rhomboid Major

A

Origin: spinous processes of T2-T5 vertebrae

Insertion: medial border of scapula from level of spine to inferior angle

Innervation: dorsal scapular nerve (C4, C5)

Action: retract scapula and rotate it to depress glenoid cavity; fix scapula to thoracic wall

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6
Q

Serratus Posterior Superior

A

Origin: nuchal ligament, spinous processes of C7-T3 vertebrae

Insertion: superior borders of 2nd-4th ribs

Innervation: 2nd-5th intercostal nerves

Action: elevate ribs

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7
Q

Serratus Posterior Inferior

A

Origin: inferior borders of 8th-12th ribs near their angles

Insertion: spinous processes of T11-L2 vertebrae

Innervation: 9th-11th intercostal nerves, subcostal (T12) nerve

Action: depress ribs

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8
Q

Erector Spinae – Iliocostalis

A

Origin: arises by broad tendon from posterior part of iliac crest, posterior surface of sacrum, sacro-iliac ligaments, sacral and inferior lumbar spinous processes, and supraspinous ligament

Insertion: fibers run superiorly to angles of lower ribs and cervical transverse processes

Innervation: posterior rami of spinal nerves

Action: bilaterally-extend vertebral column and head; as back is flexed, control movement by gradually lengthening their fibers
Unilaterally-laterally flex vertebral column

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9
Q

Erector Spinae – Longissimus

A

Origin: arises by broad tendon from posterior part of iliac crest, posterior surface of sacrum, sacro-iliac ligaments, sacral and inferior lumbar spinous processes, and supraspinous ligament

Insertion: fibers run superiorly to ribs between tubercles and angles to transverse processes in thoracic and cervical regions and to mastoid process of temporal bone

Innervation: posterior rami of spinal nerves

Action: bilaterally-extend vertebral column and head; as back is flexed, control movement by gradually lengthening their fibers
Unilaterally-laterally flex vertebral column

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10
Q

Erector Spinae – Spinalis

A

Origin: arises by broad tendon from posterior part of iliac crest, posterior surface of sacrum, sacro-iliac ligaments, sacral and inferior lumbar spinous processes, and supraspinous ligament

Insertion: fibers run superiorly to spinous processes in upper thoracic region and to cranium

Innervation: posterior rami of spinal nerves

Action: bilaterally-extend vertebral column and head; as back is flexed, control movement by gradually lengthening their fibers
Unilaterally-laterally flex vertebral column

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11
Q

Splenius Capitis

A

Origin: arises from nuchal ligament and spinous processes of C7-T3 or T4 vertebrae

Insertion: fibers run superolaterally to mastoid process of temporal bone and lateral third of superior nuchal line of occipital bone

Innervation: posterior rami of spinal nerves

Action: laterally flex neck and rotate head to side of active muscles
Acting with splenius cervicis-extend head and neck

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12
Q

Splenius Cervicis

A

Origin: arises from spinous processes of T3-T6 vertebrae

Insertion: tubercles of transverse processes of C1-C3 or C4 vertebrae

Innervation: posterior rami of spinal nerves

Action: laterally flex neck and rotate head to side of active muscles
Acting with splenius capitis-extend head and neck

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13
Q

Semispinalis (Capitis and Cervicis)

A

Origin: arises from transverse processes of C4-T10 vertebrae

Insertion: fibers run superomedially to occipital bone and spinous processes in upper thoracic and cervical regions, spanning four to six segments

Innervation: posterior rami of spinal nerves

Action: extends heads and thoracic and cervical regions of vertebral column and rotates them contralaterally

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14
Q

Multifidus

A

Origin: arises from posterior sacrum, posterior superior iliac spine of ilium,aponeurosis of erector spinae, sacro-iliac ligaments, mammillary processes of lumbar vertebrae, transverse processes of thoracic vertebrae, and articular processes of C4-C7

Insertion: thickest in lumbar region, fibers pass obliquely superomedially to entire length of spinous processes for vertebrae located two to four segments superior to origin

Innervation: posterior rami of spinal nerves

Action: unilateral contraction rotates to contralateral side, stabilizes vertebrae during local movements of vertebral column

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15
Q

Rotatores (brevis and longus)

A

Origin: arises from transverse processes of vertebrae; are best developed in thoracic region

Insertion: fibers pass superomedially to attach to junction of lamina and transverse process or spinous process of vertebrae immediately (brevis) or two segments (longus) superior to vertebra of origin

Innervation: posterior rami of spinal nerves

Action: may function as organs of proprioception; possibly stabilize vertebrae and assist with local extension and rotatory movements of vertebral column

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16
Q

Obliquus Capitis Inferior

A

Origin: spinous processes of the C2 vertebrae

Insertion: transverse processes of the C1 vertebrae

Innervation: subocciptal nerve (C1)

Action: bilaterally extends head; unilaterally rotates head to same side

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17
Q

Obliquus Capitis Superior

A

Origin: transverse processes of C1

Insertion: occipital bone between the superior and inferior nuchal lines

Innervation: suboccipital nerve (C1)

Action: bilaterally extends head; unilaterally tilts head to same side, rotates to opposite side

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18
Q

Rectus Capitis Posterior Major

A

Origin: spinous processes of C2 vertebrae

Insertion: lateral part of inferior nuchal line of occipital bone

Innervation: suboccipital nerve (C1)

Action: bilaterally extends head; unilaterally rotates head to same side

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19
Q

Rectus Capitis Posterior Minor

A

Origin: posterior tubercle on the posterior arch of C1 vertebra

Insertion: medial third of the inferior nuchal line

Innervation: suboccipital nerve (C1)

Action: bilaterally extends head; unilaterally rotates head to same side

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19
Q

Sternocleidomastoid

A

Origin: lateral surface of mastoid process of temporal bone and lateral half of superior nuchal line

Insertion: sternal head - anterior surface of manubrium of sternum
Clavicular head - superior surface of medial third of clavicle

Innervation: spinal accessory nerve (CN XI; motor), C2 and C3 nerves (pain and proprioception)

Action: unilaterally tilts head to same side and rotates it so face is turned superiorly toward opposite side
Bilaterally extends neck at atlanto-occipital joints; flexes cervical vertebrae so that chin approaches manubrium; extends superior cervical vertebrae while flexing inferior vertebrae so chin is thrust forward with head kept level
With cervical vertebrae fixed, may elevate manubrium and medial end of clavicles, assisting pump-handle action of deep respiration

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20
Q

Anterior Scalene

A

Origin: anterior tubercles of transverse processes of C3-C6 vertebrae

Insertion: 1st rib

Innervation: cervical spinal nerves C4-C6

Action: flexes neck laterally; elevates 1st rib during forced inspiration

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21
Q

Middle Scalene

A

Origin: posterior tubercles of transverse processes of C4-C7 vertebrae

Insertion: superior surface of 1st rib; posterior to groove for subclavian artery

Innervation: anterior rami of cervical spinal nerves

Action: flexes neck laterally; elevates 1st rib during forced inspiration

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22
Q

Posterior Scalene

A

Origin: posterior tubercles of transverse processes of C4-C6 vertebrae

Insertion: external border of 2nd rib

Innervation: anterior rami of cervical spinal nerves C7 and C8

Action: flexes neck laterally; elevates 2nd rib during forced inspiration

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23
Q

Deltoid

A

Origin: lateral third of clavicle; acromion and spine of scapula

Insertion: deltoid tuberosity of humerus

Innervation: axillary nerve (C5, C6)

Action: clavicular (anterior) part flexes and medially rotates shoulder joint; acromial (middle) part abducts shoulder joint; spinal (posterior) part extends and laterally rotates shoulder joint

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24
Q

Supraspinatus

A

Origin: supraspinous fossa of scapula

Insertion: superior facet of greater tubercle of humerus

Innervation: suprascapular nerve (C4, C5, C6)

Action: initiates and assists deltoid in abduction of shoulder joint and acts with other rotator cuff muscles

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25
Q

Infraspinatus

A

Origin: infraspinous fossa of scapula

Insertion: middle facet of greater tubercle of humerus

Innervation: suprascapular nerve (C5, C6)

Action: laterally rotate shoulder joint; help hold humeral head in glenoid cavity of scapula

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26
Q

Teres Minor

A

Origin: middle part of lateral border of scapula

Insertion: inferior facet of greater tubercle of humerus

Innervation: axillary nerve (C5, C6)

Action: laterally rotate shoulder joint; help hold humeral head in glenoid cavity of scapula

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27
Q

Teres Major

A

Origin: inferior part of lateral border of scapula and posterior surface of inferior angle of scapula

Insertion: medial lip of intertubercular sulcus of humerus

Innervation: lower subscapular nerve (C5, C6)

Action: adducts and medially rotates shoulder joint

28
Q

Subscapularis

A

Origin: subscapular fossa (most of anterior surface of scapula)

Insertion: lesser tubercle of humerus

Innervation: upper and lower subscapular nerves (C5, C6, C7)

Action: medially rotates and adducts shoulder joint; helps hold humeral head in glenoid cavity

29
Q

Pectoralis Major

A

Origin: clavicular head-anterior surface of medial half of clavicle
sternocostal head-anterior surface of sternum, superior six costal cartilages, aponeurosis of external oblique muscle

Insertion: lateral lip of intertubercular sulcus (groove) of humerus

Innervation: lateral and medial pectoral nerves, clavicular head (C5, C6), sternocostal head (C7, C8, T1)

Action: adducts and medially rotates shoulder joint, draws scapula anteriorly and inferiorly
Acting alone, clavicular head flexes shoulder joint and sternocostal head extends it from the flexed portion

30
Q

Pectoralis Minor

A

Origin: 3rd-5th ribs near their costal cartilages

Insertion: medial border and superior surface of coracoid process of scapula

Innervation: medial pectoral nerve (C8, T1)

Action: stabilizes scapula by drawing inferiorly and anteriorly against thoracic wall

31
Q

Subclavius

A

Origin: junction of 1st rib and its costal cartilage

Insertion: inferior surface of middle third of clavicle

Innervation: subclavian nerve (C5, C6)

Action: anchors and depresses clavicle

32
Q

Serratus Anterior

A

Origin: external surfaces of lateral parts of 1st-8th ribs

Insertion: anterior surface of medial border of scapula

Innervation: long thoracic nerve (C5, C6,C7)

Action: protracts scapula and holds against thoracic wall; rotates scapula

33
Q

Omohyoid

A

Origin: superior border of scapula near suprascapular notch

Insertion: inferior border of hyoid

Innervation: C1-C3 by a branch of ansa cervicalis

Action: depresses, retracts, and steadies hyoid

34
Q

Biceps Brachii

A

Origin: short head - tip of coracoid process of scapula
Long head - supraglenoid tubercle of scapula

Insertion: tuberosity of radius and fascia of forearm via bicipital aponeurosis

Innervation: musculocutaneous nerve (C5, C6)

Action: supinates forearm and when it is supinated, flexes elbow joint; flexes shoulder joint; short head resists dislocation of shoulder

35
Q

Brachialis

A

Origin: distal half of anterior surface of humerus

Insertion: coronoid process and tuberosity of ulna

Innervation: musculocutaneous nerve (C5, C6)

Action: flexes elbow joint in all positions

36
Q

Coracobrachialis

A

Origin: tip of coracoid process of scapula

Insertion: middle third of medial surface of humerus

Innervation: musculocutaneous nerve (C5, C6, C7)

Action: helps flex and adduct shoulder joint; resists dislocation of shoulder

37
Q

Triceps Brachii

A

Origin: long head - infraglenoid tubercle of scapula
Lateral head - posterior surface of humerus, superior to radial groove
Medial head - posterior surface of humerus, inferior to radial groove

Insertion: proximal end of olecranon of ulna and fascia of forearm

Innervation: radial nerve (C6, C7, C8)

Action: chief extensor of elbow joint; long head extends shoulder joint and resists dislocation of humerus (especially important during abduction)

38
Q

Brachioradialis

A

Origin: proximal two thirds of lateral supra-epicondylar ridge of humerus

Insertion: lateral surface of distal end of radius proximal to styloid process

Innervation: radial nerve (C5, C6, C7)

Action: relatively weak flexion of elbow joint, maximal when forearm is in mid pronated position

39
Q

Extensor Carpi Radialis Longus

A

Origin: lateral supra-epicondylar ridge of humerus

Insertion: dorsal aspect of base of 2nd metacarpal

Innervation: radial nerve (C6, C7)

Action: extend and abduct wrist joint; extensor carpi radialis brevis active during fist clenching

40
Q

Extensor Carpi Radialis Brevis

A

Origin: lateral epicondyle of humerus

Insertion: dorsal aspect of base of 3rd metacarpal

Innervation: deep branch of radial nerve (C7, C8)

Action: extend and abduct wrist joint; extensor carpi radialis brevis active during fist clenching

41
Q

Extensor Digitorum

A

Origin: lateral epicondyle of humerus

Insertion: extensor expansions of medial four fingers

Innervation: posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve

Action: extend wrist joint; extend medial four fingers primarily at metacarpophalangeal joints, secondarily at interphalangeal joints

42
Q

Extensor Digiti Minimi

A

Origin: lateral epicondyle of humerus

Insertion: extensor expansion of 5th finger

Innervation: posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve

Action: extends wrist joint; extends 5th fingers primarily at metacarpophalangeal joints, secondarily at interphalangeal joints

43
Q

Extensor Carpi Ulnaris

A

Origin: lateral epicondyle of humerus; posterior border of ulna via a shared aponeurosis

Insertion: dorsal aspect of base of 5th metacarpal

Innervation: posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve

Action: extends and adducts wrist joint (also active during fist clenching)

44
Q

Supinator

A

Origin: lateral epicondyle of humerus, radial collateral and anular ligaments, supinator fossa, crest of ulna

Insertion: lateral, posterior, and anterior surfaces of proximal third of radius

Innervation: deep branch of radial nerve (C7, C8)

Action: supinates forearm; rotates radius to turn palm anteriorly or superiorly (if elbow is flexed)

45
Q

Abductor Pollicis Longus

A

Origin: posterior surface of proximal halves of ulna, radius, and interosseous membrane

Insertion: base of 1st metacarpal

Innervation: posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve

Action: extends wrist joint; abducts thumb and extends it at carpometacarpal joint

46
Q

Extensor Pollicis Longus

A

Origin: posterior surface of middle third of ulna and interosseous membrane

Insertion: dorsal aspect of base of distal phalanx of thumb

Innervation: posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve

Action: extends wrist joint; extends distal phalanx of thumb at interphalangeal joint; extends metacarpophalangeal and carpometacarpal joints

47
Q

Extensor Pollicis Brevis

A

Origin: posterior surface of distal third of radius and interosseous membrane

Insertion: dorsal aspect of base of proximal phalanx of thumb

Innervation: posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve

Action: extends wrist joint; extends proxima; phalanx of thumb at metacarpophalangeal joint; extends carpometacarpal joint

48
Q

Extensor Indicis

A

Origin: posterior surface of distal third of ulna and interosseous membrane

Insertion: extensor expansion of 2nd finger

Innervation: posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve

Action: extends wrist joint; extends 2nd finger (enabling its independent extension); helps extend hand at wrist

49
Q

Pronator Teres

A

Origin: Ulnar head - coronoid process of ulna
Humeral head - medial epicondyle of humerus

Insertion: middle convexity of lateral surface of radius

Innervation: median nerve (C6, C7)

Action: pronates and flexes forearm

50
Q

Flexor Carpi Radialis

A

Origin: medial epicondyle of humerus

Insertion: base of 2nd (3rd) metacarpal

Innervation: median nerve (C6, C7)

Action: flexes and abducts hand at wrist

51
Q

Palmaris Longus

A

Origin: medial epicondyle of humerus

Insertion: distal half of flexor retinaculum, palmar aponeurosis

Innervation: median nerve (C7, C8)

Action: flexes hand (at wrist) and tenses palmar aponeurosis

52
Q

Flexor Carpi Ulnaris

A

Origin: olecranon and posterior border of ulna (via aponeurosis)

Insertion: pisiform, hook of hamate, 5th metacarpal

Innervation: ulnar nerve (C7, C8)

Action: flexes and adducts hand at wrist

53
Q

Flexor Digitorum Superficialis

A

Origin: humero-ulnar head - medial epicondyle of humerus and coronoid process of ulna
Radial head - oblique line of radius

Insertion: shafts of middle phalanges of medial four digits

Innervation: median nerve (C7, C8, T1)

Action: flexes wrist joint; flexes proximal interphalangeal joints of middle four digits; acting more strongly, it also flexes proximal phalanges at metacarpophalangeal joints

54
Q

Flexor Digitorum Profundus

A

Origin: proximal three quarters of medial and anterior surfaces of ulna and interosseous membrane

Insertion: bases of distal phalanges of 2nd, 3rd, 4th, and 5th digits

Innervation: lateral part (to digits 2 and 3) - median nerve (C8, T1) (anterior interosseous branch)
Medial part (to digits 4 and 5) - ulnar nerve (C8, T1)

Action: flexes wrist joint; flexes distal interphalangeal joints of digits 2, 3, 4, and 5; assists with wrist flexion

55
Q

Flexor Pollicis Longus

A

Origin: anterior surface of radius and adjacent interosseous membrane

Insertion: base of distal phalanx of thumb

Innervation: anterior interosseous nerve, from median nerve (C8, T1)

Action: flexes wrist joint; flexes metacarpophalangeal and interphalangeal joints of thumb

56
Q

Pronator Quadratus

A

Origin: distal quarter of anterior surface of ulna

Insertion: distal quarter of anterior surface of radius

Innervation: anterior interosseous nerve, from median nerve (C8, T1)

Action: pronates forearm; deep fibers bind radius and ulna together

57
Q

Opponens Pollicis

A

Origin: flexor retinaculum and tubercles of scaphoid and trapezium

Insertion: Lateral side of 1st metacarpal

Innervation: recurrent branch of median nerve (C8, T1)

Action: to oppose thumb, it draws 1st metacarpal medially to center of palm and rotates it medially

58
Q

Abductor Pollicis Brevis

A

Origin: flexor retinaculum and tubercles of scaphoid and trapezium

Insertion: lateral side of base of proximal phalanx of thumb

Innervation: recurrent branch of median nerve (C8, T1)

Action: abducts thumb; helps oppose it

59
Q

Flexor Pollicis Brevis

A

Origin: flexor retinaculum and tubercles of scaphoid and trapezium

Insertion: lateral side of base of proximal phalanx of thumb

Innervation: superficial head - recurrent branch of median nerve (C8, T1)
Deep head - deep branch of ulnar nerve (C8, T1)

Action: flexes thumb

60
Q

Adductor Pollicis

A

Origin: oblique head - bases of 2nd and 3rd metacarpals, capitate, adjacent carpals

Insertion: medial side of base of proximal phalanx of thumb

Innervation: deep branch of ulnar nerve (C8, T1)

Action: adducts thumb toward lateral border of palm

61
Q

Abductor Digiti Minimi

A

Origin: pisiform

Insertion: medial side of base of proximal phalanx of 5th finger

Innervation: deep branch of ulnar nerve (C8, T1)

Action: abducts 5th finger; assists in flexion of its proximal phalanx

62
Q

FLexor Digiti Minimi Brevis

A

Origin: hook of hamate and flexor retinaculum

Insertion: medial side of base of proximal phalanx of 5th finger

Innervation: deep branch of ulnar nerve (C8, T1)

Action: flexes proximal phalanx of 5th finger

63
Q

Opponens Digiti Minimi

A

Origin: hook of hamate and flexor retinaculum

Insertion: medial border of 5th metacarpal

Innervation: deep branch of ulnar nerve (C8, T1)

Action: draws 5th metacarpal anterior and rotates it, bringing 5th finger into opposition with thumb

64
Q

Lumbricals (1 and 2)

A

Origin: lateral two tendons of flexor digitorum profundus (as unipennate muscles)

Insertion: lateral sides of extensor expansions of 2nd-5th fingers

Innervation: median nerve (C8, T1)

Action: flex metacarpophalangeal joints; extend interphalangeal joints of 2nd-5th fingers

65
Q

Lumbricals (3 and 4)

A

Origin: medial three tendons of flexor digitorum profundus (as biennale muscles)

Insertion: lateral sides of extensor expansions of 2nd-5th fingers

Innervation: deep branch of ulnar nerve (C8, T1)

Action: flex metacarpophalangeal joints; extend interphalangeal joints of 2nd-5th fingers

66
Q

Dorsal Interossei (1-4)

A

Origin: adjacent sides of two metacarpals (as bipennate muscles)

Insertion: bases of proximal phalanges; extensor expansions of 2nd-4th fingers

Innervation: deep branch of ulnar nerve (C8, T1)

Action: abducts 2nd-4th fingers from axial line; act with lumbricals in flexing metacarpophalangeal joints and extending interphalangeal joints

67
Q

Palmar Interossei (1-3)

A

Origin: palmar surfaces of 2nd, 4th, and 5th metacarpals (as unipennate muscles)

Insertion: bases of proximal phalanges; extensor expansions of 2nd, 4th, and 5th fingers

Innervation: deep branch of ulnar nerve (C8, T1)

Action: adducts 2nd, 4th, and 5th fingers toward axial line; assist lumbricals in flexing metacarpophalangeal joints and extending interphalangeal joints

Gross Anatomy (2 decks)

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