Muscular System - Upper Flashcards

1
Q

How are head and neck muscles organized?

A

based on location and/or function

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2
Q

Muscles of the Scalp

What is the muscle of the scalp?

A

occipitofrontalis muscle

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3
Q

Muscles of the Scalp

What forms the occipitofrontalis muscle?

A

frontal belly + occipital belly connected by epicranial aponeurosis

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4
Q

Muscles of the Scalp

What does the frontal belly do?

A

wrinkles forehead skin, raises eyebrows

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5
Q

Muscles of the Scalp

What is the epicranial aponeurosis?

A

flat tendon – sheet of connective tissue

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6
Q

Muscles of Facial Expression

  • origin
  • insertion
  • nerve/innervation
A

O: skull bones

I: skin of face

N: CN VII

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7
Q

Muscles of Facial Expression

What does contraction of muscle cause?

A

different facial expressions

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8
Q

Muscles of Facial Expression

How are muscles classified? (3)

A
  • muscles around orbital cavity
  • muscles around nasal cavity
  • muscles around oral cavity
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9
Q

Muscles of Facial Expression

What is the muscle around the orbital cavity? What does it do?

A

orbicularis oculi – completely surrounds orbit and closes eyelids

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10
Q

Muscles of Facial Expression

What is the muscle around the nasal cavity? What does it do?

A

nasalis muscle – bridges over nose and flares the nostrils

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11
Q

Muscles of Facial Expression

What is the muscle around the oral cavity? What does it do?

A

orbicularis oris – completely surrounds oral fissure, and closes/purses lips

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12
Q

Muscles of Mastication

What are the 4 muscles?

A

masseter
temporalis
medial pterygoid
lateral pterygoid

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13
Q

Muscles of Mastication

What are all muscles innervated by?

A

mandibular branch/division of CN V

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14
Q

Muscles of Mastication

Masseter

  • origin
  • insertion
  • function
A

O: zygomatic arch

I: ramus of mandible (lateral surface)

F:

  • elevates mandible
  • clenches teeth
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15
Q

Muscles of Mastication

Temporalis

  • origin
  • insertion
  • function
A

O: temporal fossa of skull

I: coronoid process of mandible

F: elevates mandible

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16
Q

Muscles of Mastication

Medial Pterygoid

  • origin
  • insertion
  • function
A

O: sphenoid bone

I: medial surface of ramus of mandible

F:

  • elevates mandible, and moves it side to side
  • contralateral deviation (deviates mandible to opposite side)
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17
Q

Muscles of Mastication

Lateral Pterygoid

  • origin
  • insertion
  • function
A

O: sphenoid bone

I: condyle of mandible, and articular disc of TMJ

F:

  • protrudes mandible, and moves it side to side
  • contralateral deviation (deviates mandible to opposite side)
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18
Q

Extraocular Muscles

How many muscles are there? What do they do?

A

7 muscles that either move eyeball in different directions, OR elevate upper eyelid

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19
Q

Extraocular Muscles

What does the levator palpebrae superioris do?

A

attaches to upper eyelid

elevates superior eyelid
innervated by CN III, IV, VI

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20
Q

Extraocular Muscles

What are the muscles innervated by?

A

CN III, IV, VI

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21
Q

Pharyngeal Muscles

What are the 2 types of muscles?

A

longitudinal muscles

circular muscles

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22
Q

Pharyngeal Muscles

What do longitudinal muscles do?

A

shorten pharynx, and elevate larynx (laryngeal elevators)

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23
Q

Pharyngeal Muscles

What do circular muscles do?

A

constrict pharynx (pharyngeal constrictor muscles)

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24
Q

Pharyngeal Muscles

What are the muscles innervated by?

A

CN X (except stylopharyngeus)

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25
Q

Muscles of Soft Palate

  • origin (2)
  • insertion (2)
A

first group
O: base of cranium
I: soft palate

or

second group
O: soft palate
I: tongue or pharynx

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26
Q

Muscles of Soft Palate

What does the first group of muscles do?

A

elevates or stretches soft palate

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27
Q

Muscles of Soft Palate

What does the second group of muscles do?

A

depresses soft palate

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28
Q

Muscles of Soft Palate

What are the muscles innervated by?

A

CN X (except tensor veli palatini)

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29
Q

Muscles of Tongue

What are the 2 types of muscles?

A

intrinsic muscles

extrinsic muscles

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30
Q

Muscles of Tongue

Intrinsic Muscles

  • origin
  • insertion
A

O: inside tongue

I: inside tongue

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31
Q

Muscles of Tongue

Extrinsic Muscles

  • origin
  • insertion
A

O: soft palate, mandible, styloid process, or hyoid bone

I: tongue

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32
Q

Muscles of Tongue

What are the muscles innervated by?

A

CN XII (except palatoglossus)

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33
Q

Muscles of Larynx

What are the 2 types of muscles?

A

intrinsic muscles

extrinsic muscles

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34
Q

Muscles of Larynx

Intrinsic Muscles

  • location
  • function
A

stretched between laryngeal cartilages

change length or tension of vocal cords during phonation and respiration

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35
Q

Muscles of Larynx

Extrinsic Muscles

  • types (2)
  • function
A

suprahyoid muscle of the neck: elevate neck

infrahyoid muscle of the neck: depress neck

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36
Q

Muscles of Larynx

What are the muscles innervated by?

A

CN X

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37
Q

Muscles of Neck

What are the 2 groups of muscles in the neck?

A

superficial

deep

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38
Q

Muscles of Neck - Superficial

What are the 3 superficial muscles?

A

sternocleidomastoid (SCM)
infrahyoid
suprahyoid

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39
Q

Muscles of Neck - Superficial

Sternocleidomastoid (SCM)

  • origin
  • insertion
  • function
  • nerve/innervation
A

O: sternum and clavicle

I: mastoid process of temporal bone

F: unilaterally bends neck towards shoulder, and rotates head contralaterally

N: by CN XI

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40
Q

Muscles of Neck - Superficial

Infrahyoid

  • origin
  • insertion
  • function
  • nerve/innervation
A

O: sternum

I: thyroid cartilage OR hyoid bone

F: depress hyoid bones and larynx

N: by ansa cervicalis of cervical plexus

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41
Q

Muscles of Neck - Superficial

Suprahyoid

  • origin
  • insertion
  • function
  • nerve/innervation
A

O: temporal bone OR mandible

I: hyoid bone

F: elevate hyoid bone and larynx OR depress mandible

N: by mandibular division of CN V or CN VII

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42
Q

Muscles of Neck - Deep

What are the 2 deep muscles?

A
  • scalene (anterior, middle, and posterior)

- prevertebral

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43
Q

Muscles of Neck - Deep

Scalene (anterior, middle, and posterior)
dont need to know origins

  • origin
  • insertion
  • function
  • nerve/innervation
A

O: transverse processes of cervical vertebrae (except CI)

I: first or second ribs

F: elevate first two ribs OR laterally flex neck

N: by anterior rami of some cervical spinal nerves

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44
Q

Muscles of Neck - Deep

Prevertebral

  • function
  • nerve/innervation
A

F: lateral flex head and neck

N: by anterior rami of some cervical spinal nerves

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45
Q

What are the 4 types of trunk muscles?

A

back, thoracic, abdominal, and pelvic musculatures

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46
Q

Muscles of Back

How are muscles classified?

A

into 3 distinct layers (superficial, intermediate, and deep)

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47
Q

Muscles of Back

What are the extrinsic back muscles?

A

superficial and intermediate layers

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48
Q

Muscles of Back

What are the intrinsic back muscles?

A

deep layer

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49
Q

Muscles of Back - Superficial

What do superficial muscles do?

A

connect upper limbs to trunk, and position pectoral girdle and upper limb

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50
Q

Muscles of Back - Superficial

What are superficial muscles innervated by?

A

anterior rami of spinal nerves

51
Q

Muscles of Back - Superficial

What are the 5 muscles?

A
trapezius
latissimus dorsi
levator scapulae
rhomboid major
rhomboid minor
52
Q

Muscles of Back - Superficial

Trapezius

  • main action(s)
  • nerve/innervation
A

MA: upward rotation, elevation, depression, and retraction (adduction) of scapula

N: CN XI

53
Q

Muscles of Back - Superficial

Latissimus Dorsi

  • insertion
  • main action(s)
  • nerve/innervation
A

I: intertubercular groove of humerus

MA: extension, adduction, and medial rotation of shoulder joint

N: thoracodorsal nerve

54
Q

Muscles of Back - Superficial

Levator Scapulae

  • main action(s)
  • nerve/innervation
A

MA: elevation of scapula

N: dorsal scapular nerve (C5), and C3, C4 spinal nerves

55
Q

Muscles of Back - Superficial

Rhomboid Major

  • main action(s)
  • nerve/innervation
A

MA: retraction (adduction), and elevation of scapula

N: dorsal scapular nerve

56
Q

Muscles of Back - Superficial

Rhomboid Minor

  • main action(s)
  • nerve/innervation
A

MA: retraction (adduction) and elevation of scapula

N: dorsal scapular nerve

57
Q

Muscles of Back - Intermediate

What are the intermediate back muscles?

A

accessory respiratory muscles

58
Q

Muscles of Back - Intermediate

What are the intermediate back muscles innervated by?

A

anterior rami of spinal nerves

59
Q

Muscles of Back - Intermediate

What are the 2 muscles?

A

serratus posterior superior
serratus posterior inferior

60
Q

Muscles of Back - Intermediate

Serratus Posterior Superior

  • main action(s)
  • nerve/innervation
A

MA: elevation of ribs II-V

N: anterior rami of T2-T5

61
Q

Muscles of Back - Intermediate

Serratus Posterior Inferior

  • main action(s)
  • nerve/innervation
A

MA: depression of ribs IX-XII

N: anterior rami of T9-T11

62
Q

Muscles of Back - Deep

What are the 3 groups that deep muscles divide into?

A

erector spinae
transversospinalis
segmental

63
Q

Muscles of Back - Deep

What does the erector spinae group do?

A

maintain erect position of trunk and neck, and extend and rotate vertebral column

64
Q

Muscles of Back - Deep

What does the transversospinalis group do?

A

maintain erect position of trunk and neck, and extend and rotate vertebral column

65
Q

Muscles of Back - Deep

What does the segmental group do?

A

extends or laterally flexes vertebral column, or elevates ribs

66
Q

Muscles of Back - Deep

What are muscles innervated by?

A

posterior rami of spinal nerves

67
Q

Muscles of Back - Deep

What are the 3 muscles in the neck?

A

splenius capitis

splenius cervicis

68
Q

Muscles of Back - Deep

Splenius Capitis

  • main action(s)
  • nerve/innervation
A

MA: extension and rotation of head

N: posterior rami of cervical spinal nerves

69
Q

Muscles of Back - Deep

Splenius Cervicis

  • main action(s)
  • nerve/innervation
A

MA: extension and rotation of neck

N: posterior rami of cervical spinal nerves

70
Q

Muscles of Back - Deep, Erector Spinae

What are the 3 muscles of the erector spinae group?

A

iliocostalis
longissimus
spinalis

71
Q

Muscles of Back - Deep, Erector Spinae

Iliocostalis

  • main action(s)
  • nerve/innervation
A

MA: extension and lateral flexion of vertebral column

N: posterior rami of corresponding spinal nerves

72
Q

Muscles of Back - Deep, Erector Spinae

Longissimus

  • main action(s)
  • nerve/innervation
A

MA: extension and lateral flexion of vertebral column and head

N: posterior rami of corresponding spinal nerves

73
Q

Muscles of Back - Deep, Erector Spinae

Spinalis

  • main action(s)
  • nerve/innervation
A

MA: extension of vertebral column and head

N: posterior rami of corresponding spinal nerves

74
Q

Muscles of Back - Deep

What are the 3 muscles of the transversospinalis group?

A

semispinalis
multifidus
rotatores

75
Q

Muscles of Back - Deep, Segmental

What are the 3 muscles of the segmental group?

A

levator costarum
intertransversarii
interspinales

76
Q

Muscles of Back - Deep, Segmental

Levator Costarum

  • main action
  • nerve/innervation
A

MA: elevation of ribs

N: posterior rami of corresponding spinal nerves

77
Q

Muscles of Back - Deep, Segmental

Intertransversarii

  • main action
  • nerve/innervation
A

MA: lateral flexion of vertebral column

N: posterior rami of corresponding spinal nerves

78
Q

Muscles of Back - Deep, Segmental

Interspinales

  • main action
  • nerve/innervation
A

MA: extension of vertebral column

N: posterior rami of corresponding spinal nerves

79
Q

Muscles of Thorax

What are the 2 types of muscles?

Where do they originate and insert?

A

extrinsic muscles: originate from thorax, and insert to upper limb

intrinsic muscles: originate and insert in thorax

80
Q

Muscles of Thorax

What are the 4 types of extrinsic muscles?

A

pectoralis major
pectoralis minor
serratus anterior
subclavius

81
Q

Muscles of Thorax - Extrinsic

Pectoralis Major

  • origin
  • insertion
  • main acation(s)
  • nerve/innervation
A

O: medial half of clavicle and sternum

I: lateral lip of intertubercular groove of humerus

MA: horizontal adduction and medial rotation of shoulder joint

N: medial and lateral pectoral nerves

82
Q

Muscles of Thorax - Extrinsic

Pectoralis Minor

  • insertion
  • main acation(s)
  • nerve/innervation
A

I: coracoid process of scapula

MA: protraction (abduction) of scapula

N: medial and lateral pectoral nerves

83
Q

Muscles of Thorax - Extrinsic

Serratus Anterior

  • origin
  • insertion
  • main acation(s)
  • nerve/innervation
A

O: ribs I-IX

I: medial border of scapula

MA: protraction (abduction) and upward rotation of scapula

N: long thoracic nerve (roots of C5-C7)

84
Q

Muscles of Thorax - Intrinsic

What do intercostal muscles do?

A

mainly involved in respiration by increasing/decreasing thoracic cavity volume during inhalation/exhalation

85
Q

Muscles of Thorax - Intrinsic

What are the 3 main openings of the diaphragm?

What are they passages for?

A

aortic opening: for passage of aorta, at level of TXII

esophageal hiatus: for passage of esophagus, at level of TX

inferior vena cava opening: for passage of inferior vena cava, at level of TVIII

86
Q

Muscles of Thorax - Intrinsic

What are the 3 intrinsic muscles?

A

external intercostal
internal intercostal
diaphragm

87
Q

Muscles of Thorax - Intrinsic

External Intercostal

  • origin
  • insertion
  • main action(s)
  • nerve/innervation
A

O: inferior border of rib above

I: superior border of rib below

MA: elevation of rib above

N: intercostal nerves (anterior rami of TI-T11)

88
Q

Muscles of Thorax - Intrinsic

Internal Intercostal

  • origin
  • insertion
  • main action(s)
  • nerve/innervation
A

O: superior border of rib below

I: inferior border of rib above

MA: depression of rib above

N: intercostal nerves (anterior rami of TI-T11)

89
Q

Muscles of Thorax - Intrinsic

Diaphragm

  • origin
  • insertion
  • main action(s)
  • nerve/innervation
A

O: xiphoid process of sternum, lower 6 ribs, and upper 3 lumbar vertebrae

I: central tendon of diaphragm

MA: increases volume of (expands) thoracic cavity

N: phrenic nerve

90
Q

Muscles of Abdomen

What are the 2 types of muscles?

A

anterolateral wall musculatures
posterior abdominal wall musculatures

91
Q

Muscles of Abdomen

What do anterolateral wall musculatures do?

A

flexes and rotates trunk, and increase abdominal cavity pressure

92
Q

Muscles of Abdomen

What do posterior abdominal wall musculatures do?

A

extends and laterally flexes trunk, or flexes and laterally rotates hip joint

93
Q

Muscles of Abdomen - Anterolateral Abdominal Wall Muscles

What are the 4 muscles?

A

rectus abdominis
external abdominal oblique
internal abdominal oblique
transversus abdominis

94
Q

Muscles of Abdomen - Anterolateral Abdominal Wall Muscles

Rectus Abdominis

  • origin
  • insertion
  • main action(s)
  • nerve/innervation
A

O: pubic bone and pubic symphysis

I: xiphoid process and costal cartilages V-VII

MA: compression of abdominal viscera, and flexion of trunk

N: anterior rami of T7-T12

95
Q

Muscles of Abdomen - Anterolateral Abdominal Wall Muscles

External Abdominal Oblique

  • origin
  • insertion
  • main action(s)
  • nerve/innervation
A

O: lower 8 ribs

I: iliac crest, pubic bone, and linea alba

MA: compression of abdominal viscera, flexion, and contralateral rotation of trunk

N: anterior rami of T7-T12

96
Q

Muscles of Abdomen - Anterolateral Abdominal Wall Muscles

Internal Abdominal Oblique

  • origin
  • insertion
  • main action(s)
  • nerve/innervation
A

O: iliac crest and inguinal ligament

I: lower 4 ribs and linea alba

MA: compression of abdominal viscera, flexion and ipsilateral rotation of trunk

N: anterior rami of T7-L1

97
Q

Muscles of Abdomen - Anterolateral Abdominal Wall Muscles

Transversus Abdominus

  • origin
  • insertion
  • main action(s)
  • nerve/innervation
A

O: iliac crest, inguinal ligament, and lower 6 ribs

I: linea alba

MA: compression of abdominal viscera

N: anterior rami of T7-L1

98
Q

Muscles of Abdomen - Anterolateral Abdominal Wall Muscles

What is aponeurosis?

A

sheet-like tendon that attaches anterolateral abdominal muscles (except rectus abdominis) to their insertion

99
Q

Muscles of Abdomen - Anterolateral Abdominal Wall Muscles

What is the inguinal ligament?

A

inferior free border of aponeurosis of external abdominal oblique muscle stretched between anterior superior iliac spine (ASIS) and pubic tubercle

100
Q

Muscles of Abdomen - Anterolateral Abdominal Wall Muscles

What is the rectus sheath formed by?

A

fibrous sheath formed by aponeuroses of external, internal, and transversus abdominis muscle

almost complete invests rectus abdominis muscle

101
Q

Muscles of Abdomen - Anterolateral Abdominal Wall Muscles

What is the linea alba?

What is it formed by?

Where it it located?

A

band of dense connective tissue formed by union of aponeuroses of anterolateral abdominal muscles in midline

extends from xiphoid process to pubic symphysis

102
Q

Muscles of Abdomen - Anterolateral Abdominal Wall Muscles

What is the inguinal canal?

What is it formed by?

What are the 2 openings?

What does it contain?

A

short oblique canal located parallel and a little above medial half of inguinal ligament

formed by and between external, internal and transversus abdominis muscles

2 openings: deep inguinal ring and superficial inguinal ring

contains spermatic cord in male, and round ligament of uterus in female

103
Q

Muscles of Abdomen - Posterior Abdominal Wall Muscles

What are the 3 muscles?

A

psoas major
iliacus
quadratus lumborum

104
Q

Muscles of Abdomen - Posterior Abdominal Wall Muscles

Psoas Major

  • origin
  • insertion
  • main action(s)
  • nerve/innervation
A

O: transverse processes and bodies of lumbar vertebrae and intervening discs

I: lesser trochanter of femur

MA: flexion and lateral rotation of hip joint

N: anterior rami of L1-L3

105
Q

Muscles of Abdomen - Posterior Abdominal Wall Muscles

Iliacus

  • origin
  • insertion
  • main action(s)
  • nerve/innervation
A

O: iliac fossa

I: lesser trochanter of femur

MA: flexion and lateral rotation of hip joint

N: femoral nerve

106
Q

Muscles of Abdomen - Posterior Abdominal Wall Muscles

Quadratus Lumborum

  • origin
  • insertion
  • main action(s)
  • nerve/innervation
A

O: transverse process of LV and iliac crest

I: transverse processes of LI-LIV and rib XII

MA: extension and lateral flexion of trunk, and fixation of rib XII

N: anterior rami of T12-L4

107
Q

Muscles of Pelvis

What are the 2 pelvic wall muscles?

Where do they originate and insert?

A

piriformis muscle
obturator internus muscle

O: pelvic cavity
I: femur

108
Q

Muscles of Pelvis

Where are perineal muscles?

A

contained within perineum

109
Q

Muscles of Pelvis - Pelvic Diaphragm

What do muscles join to form?

A

these muscles from left and right sides join together to form muscular funnel-shaped membrane located between true pelvis and perineum

110
Q

Muscles of Pelvis - Pelvic Diaphragm

What do levator ani muscles arise from?

What do its anterior fibers do?

What do its posterior fibers do?

A
  • arises from inner surface of hip bone
  • anterior fibers merge with fibers of opposite side levator ani
  • posterior fibers insert to sacrum and coccyx
111
Q

Muscles of Pelvis - Pelvic Diaphragm

Where does the coccygeus muscle originate and insert?

A

O: ischial spine

I: coccyx and sacrum

112
Q

Muscles of Pelvis - Pelvic Diaphragm

What does the muscle support?

A

supports pelvic viscera

113
Q

Muscles of Pelvis - Pelvic Diaphragm

What are the 2 muscles?

A

levator ani muscle

coccygeus muscle

114
Q

Muscles of Pelvis - Pelvic Diaphragm

What is the muscle innervated by?

A

branches from sacral plexus

115
Q

Muscles of Pelvis

What is the perineum?

A

diamond-shaped area located inferior to pelvic diaphragm between thighs

116
Q

Muscles of Pelvis

What are the boundaries of the perineum?

A

same as inferior pelvic aperture (outlet) – coccyx (posteriorly), pubic symphysis (anteriorly), and ischial tuberosities (laterally)

117
Q

Muscles of Pelvis

What is the perineum subdivided into?

A

anterior urogenital triangle and posterior anal traingle by horizontal line between ischial tuberosities

118
Q

Muscles of Pelvis

What does the urogenital triangle contain?

A

distal part of urethra, external genitalia, and perineal muscles (except external and anal sphincter)

119
Q

Muscles of Pelvis - Urogenital Triangle

What do the main muscles do?

A

cover root of external genitalia

120
Q

Muscles of Pelvis - Urogenital Triangle

What are the 2 main muscles?

A

bulbospongiosus

ischiocavernosus

121
Q

Muscles of Pelvis - Urogenital Triangle

What does bulbospongiosus do?

A

help in draining last drops of urine (in males), and acts as sphincter for vaginal opening (in females)

122
Q

Muscles of Pelvis - Urogenital Triangle

What does ischiocavernosus do?

A

assist in maintaining erection of penis or clitoris

123
Q

Muscles of Pelvis

What does the anal triangle contain?

A

anal canal surrounded by external anal sphincter muscle

124
Q

Muscles of Pelvis - Anal Triangle

What is the muscle?
What is it innervated by?

A

perineal muscle

innervated by pudendal nerve