Muscles Of The Head

Front 1

Nine groups of head muscle

Back 1

Muscles of Facial Expression

MUSCLES OF MASTICATION

MUSCLES OF BULBUS OCULI-EXTERNAL

MUSCLES OF THE TONGUE

MUSCLES OF THE PHARYNX

MUSCLES OF THE SOFT PALATE

MUSCLES OF THE LARYNX

MUSCLES OF THE HYOID APPARATUS

MUSCLES OF CERVICAL VERTEBRAE

Front 2

Muscles of Facial Expression

Back 2

• superficial

• Deep

Front 3

Muscles of Facial Expression

Superficial

Back 3

• Sphincter colli superficialis

• Platysma

• Sphincter colli profundus

Front 4

Muscles of Facial Expression

Deep

Back 4

• Lip and nose

• Eyelids, forehead and ears

• Extrinsic ear muscles

• Intrinsic ear muscles

• Middle ear muscles

Front 5

Lip and nose

Back 5

• Orbicularis oris

• Zygomaticus

• Superior and inferior incisivus

• Levator labii superioris

• Caninus

• Buccinator

• Mentalis

• Levator nasolabialis

Front 6

Eyelids, forehead and ears

Back 6

• Orbicularis oculi

• Retractor anguli oculi lateralis

• Levator anguli oculi medialis

• Levator palpebraesuperioris

• Orbitalis

• Occipitalis

• Extrinsic ear muscles

Front 7

Extrinsic ear muscles

• Rostral

Back 7

• Superficial scutuloauricularis

• Deep scutuloauricularis

• Frontoscutularis

• Frontalis

• Zygomaticoauricularis

Front 8

Extrinsic ear muscles

• Dorsal

Back 8

• Interscutularis

• Parietoscutularis

• Parietoauricularis

Front 9

Extrinsic ear muscles

• Caudal

Back 9

• Cervicoscutularis

• Superficial cervicoauricularis

• Middle cervicoauricularis

• Deep cervicoauricularis

• Parotidoauricularis

• Styloauricularis

Front 10

Intrinsic ear muscles

Back 10

• Helicis

• Helicis minor

• Tragicus

• Transversus auriculae

• Oblique auriculae

Front 11

Middle ear muscles

Back 11

• Stapedius

• Tensor tympani

Front 12

MUSCLES OF MASTICATION

Back 12

• Masseter

• Temporalis

• Pterygoideus lateralis

• Pterygoideus medialis

• Digastricus

Front 13

MUSCLES OF BULBUS OCULI-EXTERNAL

Back 13

• Dorsal and ventral oblique

• Dorsal, lateral, ventral and medial rectus

• Retractor bulbi

• Orbicularis

Front 14

MUSCLES OF THE TONGUE

Back 14

• Styloglossus

• Hyoglossus

• Genioglossus

• Lingual proper

Front 15

MUSCLES OF THE PHARYNX

Back 15

• Hyopharyngeus

• Thyropharyngeus

• Cricopharyngeus

• Stylopharyngeus

• Palatopharyngeus

• Pterygopharyngeus

Front 16

MUSCLES OF THE SOFT PALATE

Back 16

• Tensor veli palatini

• Levator veli palatini

• Palatinus

Front 17

MUSCLES OF THE LARYNX

Back 17

• Cricothyroideus

• Cricoarytenoideus dorsalis

• Cricoarytenoideus lateralis

• Thyroarytenoideus

• Vocalis

• Ventricularis

• Arytenoideus transversus

• Hyoepiglotticus

Front 18

MUSCLES OF THE HYOID APPARATUS

Back 18

• Sternohyoideus

• Thyrohyoideus

• Mylohyoideus

• Ceratohyoideus

• Geniohyoideus

• Occipitohyoideus

• Stylohyoideus

Front 19

MUSCLES OF CERVICAL VERTEBRAE

Back 19

• Rectus capitis ventralis

• Rectus capitis dorsalis major

• Rectus capitis dorsalis minor

• Rectus capitis lateralis

• Obliquus capitis cranialis

• Obliquus capitis caudalis

• Splenius capitis

• Longus capitis

Front 20

__________ best developed in the laryngeal region deep to the skin.

Back 20

Sphincter colli superficialis

Front 21

_________ a well-developed muscle sheet that takes its origin from the mid-dorsal tendinous raphe of the neck and the skin.

Back 21

Platysma

Front 22

• Action: To draw the commissure of the lips caudally.

• Innervation: Buccal branches and the caudal auricular nerve from the facial nerve

Back 22

Platysma

Front 23

__________ consists of a few thin muscle fascicles that extend dorsoventrally from the base of the ear, lateral to the masseter muscle and parotid gland

Back 23

Sphincter colli profundus

Front 24

___________ the principal component of the lips, extends from the commissural region into the lips near their free borders

Back 24

M. orbicularis oris

Front 25

Action: The muscle closes the lips of a closed mouth and is a pressor of the labial glands. The medial ones act to pull the entire nose ventrally (in sniffing)

Back 25

M. orbicularis oris

Front 26

_________ arises from the scutiform cartilage

Back 26

M. zygomaticus

Front 27

Action: To fix the angle of the mouth and draw it caudally, or to fix and draw the scutiform cartilage rostrally

Back 27

M. zygomaticus

Front 28

Action: To increase the diameter of the naris, and lift the apical portion of the superior lip.

Back 28

M. levator nasolabialis

Front 29

___________ is a flat, thin, and broad muscle (even in large dogs), lying immediately deep to the skin on the lateral surface of the nasal and maxillary bones

Back 29

M. levator nasolabialis

Front 30

_______ has developed from the deep part of the orbicularis oris.

Back 30

M. buccinator

Front 31

Action: To return food from the vestibule to the masticatory surface of the teeth.

Back 31

M. buccinator

Front 32

Action: To close the palpebral fissure.

Back 32

M. orbicularis oculi

Front 33

_______ surrounds the palpebral fissure.

Back 33

M. orbicularis oculi

Front 34

The _________________ include the superficial scutuloauricularis, deep scutuloauricularis, frontalis, frontoscutularis, and zygomaticoauricularis

Back 34

rostral extrinsic ear muscles

Front 35

Action: To fix and pull the scutiform cartilage rostrally.

Back 35

m. frontalis

Front 36

________ is a thin muscle that lies on the temporalis.

Back 36

m. frontalis

Front 37

The __________ include the cervicoscutularis, cervicoauricularis superficialis, cervicoauricularis medius and cervicoauricularis profundus

Back 37

caudal extrinsic ear muscles

Front 38

______________ formerly called the depressor auriculae, arises caudal to the laryngeal region, on or near the midline, where it blends with the cervical fascia.

Back 38

m. parotidoauricularis (parotideoauricularis)

Front 39

___________ include the masseter, temporal, lateral and medial pterygoid, and the digastricus.

Back 39

muscles of mastication

Front 40

All are innervated by the mandibular nerve from the trigeminal except for the caudal portion of the digastricus, which is innervated by the facial nerve.

Back 40

Muscles of Mastication

Front 41

Action: To raise the mandible in closing the mouth.

Back 41

M. masseter

Front 42

_________ lies on the lateral surface of the ramus of the mandible ventral to the zygomatic arch.

Back 42

M. masseter

Front 43

Action: To open the mouth

Back 43

M. digastricus

Front 44

(biventer mandibulae) runs from the paracondylar process of the occiput to the ventral border of the mandible.

Back 44

M. digastricus

Front 45

There ares even extrinsic muscles of the eyeball:

Back 45

two obliquemuscles, four recti muscles, and the retractor bulbi

Front 46

Action: To rotate the eyeball around its anterior to posterior axis so that the lateral part is moved laterally and ventrally—extorsion.

Back 46

M. obliquus ventralis

Front 47

_________ arises from the rostrolateral margin of a variably sized opening in the palatine bone adjacent to the suture between the palatine, lacrimal, and maxillary bones.

Back 47

M. obliquus ventralis

Front 48

Action: To rotate the eyeball around its anterior–posterior axis so that the dorsal part is pulled medially and ventrally—intorsion.

Back 48

M. obliquus dorsalis

Front 49

_________ or trochlearis arises from the medial border of the optic canal.

Back 49

M. obliquus dorsalis,

Front 50

___________ or straight muscles of the eyeball, include the mm. rectus lateralis, rectus medialis, rectus dorsalis, and rectus ventralis.

Back 50

mm. recti

Front 51

Action: The medial and lateral recti rotate the eyeball about a vertical axis through the equator resulting in adduction and abduction; the dorsal and ventral recti rotate the eyeball about a horizontal axis through the equator resulting in elevation and depression.

Back 51

mm. recti

Front 52

____________ arises deep to the mm. recti at the apex of the orbit, where they attach to the ventral end of the pterygoid crest and the adjacent orbital fissure

Back 52

M. retractor bulbi

Front 53

Action: To retract the eyeball. In addition, because of its essentially alternate attachments with the recti, it aids in bringing about oblique eye movements

Back 53

M. retractor bulbi

Front 54

The _____________ include the styloglossus, hyoglossus, genioglossus, and lingual intrinsic muscles.

Back 54

muscles of the tongue

Front 55

The muscles of the tongue include the styloglossus, hyoglossus, genioglossus, and lingual intrinsic muscles. These are all innervated by the ___________

Back 55

n. hypoglossus

Front 56

Action: To draw the tongue caudally when all three heads act together.

Back 56

M. styloglossus

Front 57

___________ extends from the stylohyoid bone to the tongue. It is composed of three muscle heads that insert in the tongue at different levels along its long axis.

Back 57

M. styloglossus

Front 58

Action: To retract and depress the tongue.

Back 58

M. hyoglossus

Front 59

______________ is located in the root of the tongue. It arises from the ventrolateral surface of the basihyoid and the adjoining end of the thyrohyoid bone.

Back 59

M. hyoglossus

Front 60

___________ is a thin, triangular muscle that lies in the intermandibular space, in and ventral to the tongue

Back 60

M. genioglossus

Front 61

Action: To depress the tongue. The caudal fibers draw the tongue rostrally; the rostral fibers curl the apex of the tongue ventrally

Back 61

M. genioglossus

Front 62

_________ is the intrinsic tongue musculature that consists of many muscular bundles that are located among the fascicles of insertion of the extrinsic muscles of the tongue

Back 62

M. propria linguae

Front 63

Action: To protrude the tongue and bring about complicated intrinsic, local movements; to prevent the tongue from being bitten

Back 63

M. propria linguae

Front 64

____________ are primarily associated with the laryngopharynx and include the hyopharyngeus, thyropharyngeus, cricopharyngeus, stylopharyngeus, palatopharyngeus, and pterygopharyngeus

Back 64

muscles of the pharynx

Front 65

These are all innervated by pharyngeal branches of the glossopharyngeal and vagal nerves

Back 65

Muscles of the Pharynx

Front 66

________ are closely associated with the muscles of the pharynx and include the tensor veli palatini, levator veli palatini, and the palatinus.

Back 66

muscles of the soft palate

Front 67

___________ is a small, straight muscle that runs longitudinally through the soft palate.

Back 67

M. palatinus (m. uvulae)

Front 68

Action: To shorten the palate and curl the caudal border ventrally

Back 68

M. palatinus (m. uvulae)

Front 69

__________ is a thick muscle on the lateral surface of the larynx between the thyroid lamina and the cricoid cartilage

Back 69

M. cricothyroideus

Front 70

Action: To pivot the cricoid cartilage on its thyroid articulation, thus tensing the vocal cords.

Back 70

M. cricothyroideus

Front 71

Action: To open the glottis by abducting the vocal folds.

Back 71

M. cricoarytenoideus dorsalis

Front 72

_________ arises from the entire length of the dorsolateral surface of the cricoid cartilage.

Back 72

M. cricoarytenoideus dorsalis

Front 73

________ arises from the lateral and cranial surface of the cricoid cartilage

Back 73

M. cricoarytenoideus lateralis

Front 74

Action: To pivot the arytenoid cartilage medially and close the rima glottis.

Back 74

M. cricoarytenoideus lateralis

Front 75

Action: To relax the vocal cord and constrict the glottis.

Back 75

M. thyroarytenoideus

Front 76

__________ is the parent muscle mass, which has given rise to the m. ventricularis and the m. vocalis.

Back 76

M. thyroarytenoideus

Front 77

Action: To draw the arytenoid cartilage ventrally, thus relaxing the vocal cord

Back 77

M. vocalis

Front 78

_________ is a medial division of the original thyroarytenoid muscle mass

Back 78

M. vocalis

Front 79

____________ is a cranial division of the thyroarytenoidmuscle mass, which has shifted its origin in the dog from the thyroid cartilage to the cuneiform process of the arytenoid cartilage

Back 79

M. ventricularis

Front 80

Action: To constrict the glottis and dilate the laryngeal ventricle.

Back 80

M. ventricularis

Front 81

____________ originates broadly on the muscular process of the arytenoid cartilage at the line of insertion of the thyroarytenoideus.

Back 81

M. arytenoideus transversus

Front 82

Action: To constrict the glottis and adduct the vocal folds

Back 82

M. arytenoideus transversus

Front 83

Action: To draw the epiglottis ventrally.

Back 83

M. hyoepiglotticus

Front 84

_____________ a small, spindle-shaped muscle, arises from the medial surface of the ceratohyoid bone

Back 84

M. hyoepiglotticus

Front 85

The ____________ include the sternohyoideus, sternothyroideus, thyrohyoideus, mylohyoideus, ceratohyoideus, geniohyoideus, occiptiohyoideus, and stylohyoideus

Back 85

muscles of the hyoid apparatus

Front 86

Action: To pull the basihyoid bone and tongue caudally.

Back 86

M. sternohyoideus

Front 87

Action: To draw the hyoid apparatus, larynx, and tongue caudally

Back 87

M. sternothyroideus

Front 88

Action: To draw the hyoid apparatus caudally and dorsally.

Back 88

M. thyrohyoideus

Front 89

Action: To raise the floor of the mouth and draw the hyoid apparatus rostrally.

Back 89

M. mylohyoideus

Front 90

Action: To decrease the angle formed by the thyrohyoid and ceratohyoid bones

Back 90

M. ceratohyoideus

Front 91

Action: To raise the basihyoid bone.

Back 91

M. geniohyoideus

Front 92

Action: To move the stylohyoid bone caudally

Back 92

M. occipitohyoideus

Front 93

Action: Flexion of the atlantooccipital joint.

Back 93

M. rectus capitis ventralis

Front 94

Action: Both rectus dorsalis muscles extend the atlantooccipital joint.

Back 94

M. rectus capitis dorsalis major and minor

Front 95

Action: Flexion of the atlantooccipital joint.

Back 95

M. rectus capitis lateralis

Front 96

Action: Extension of the atlantooccipital joint.

Back 96

M. obliquus capitis cranialis

Front 97

Action: Unilateral: rotation of the atlas and thus the head on the axis; bilateral: fixation of the atlantoaxial joint

Back 97

m. obliquus capitis caudalis

Front 98

_________ included here are those muscles that are primarily located in the neck with attachments to the head or thoracic limb.

Back 98

muscles of the neck

Front 99

(musculi colli)

Back 99

muscles of the neck

Front 100

muscles of the neck include the:

Back 100

• brachiocephalicus,

• omotransversarius,

• sternocephalicus,

• splenius,

• Longus capitis,

• longus colli,

• scalenus, and

• serratus ventralis cervicis.

Front 101

____________ lying on the neck deep to the m. sphincter colli superficialis and platysma as a long, flat muscle, extends between the brachium and the head and neck.

Back 101

M. brachiocephalicus

Front 102

Action: To flex the neck. In unilateral action, to bend the neck laterally, lateral flexion. When the neck is fixed, the dorsal part can act in inspiration.

Back 102

M. scalenus

Front 103

Action: To flex the neck.

Back 103

M. longus colli

Front 104

Action: To flex the atlantooccipital joint and to draw the neck ventrally.

Back 104

M. longus capitis

Front 105

Action: In unilateral action to draw the head and neck laterally, lateral flexion. It also functions in fixation of the first thoracic vertebra

Back 105

M. splenius capitis

Front 106

Action: Support of the trunk, to carry the trunk cranially and caudally; inspiration; to carry the shoulder cranial and caudal with respect to the limb.

Back 106

M. serratus ventralis cervicis

Front 107

The ______________ , musculi dorsi, include extrinsic muscles of the thoracic limb that attach to the thorax and the epaxial muscles that form a continuous column throughout most of the vertebral column.

Back 107

muscles of the dorsum

Front 108

The extrinsic thoracic limb muscles include:

Back 108

Trapezius, Lattisismus dorsi, and Rhomboideus.

Front 109

The epaxial muscles are the

Back 109

Serratus dorsalis, the Erector spinae, Transverso spinalis, Interspinalis and Intertransversarii.

Front 110

is a broad, thin, triangular muscle.

Back 110

M. trapezius

Front 111

Action: To elevate the limb and draw it cranially, to rotate the scapula.

Back 111

M. trapezius

Front 112

Action: To draw the trunk cranially and possibly laterally; extend the vertebral column; and support the limb, draw the limb against the trunk, and draw the free limb caudally during flexion of the shoulder joint.

Back 112

M. latissimus dorsi

Front 113

__________ is a flat, almost triangular muscle that lies caudal to the muscles of the scapula and brachium on the dorsal half of the lateral thoracic wall

Back 113

M. latissimus dorsi

Front 114

__________ covered by the trapezius, fans out on the neck and cranial thorax between the median line of the neck and thorax and the dorsal border of the scapula. It is in part flat and in part thick, and is divided into three parts.

Back 114

M. rhomboideus

Front 115

Action: To elevate the limb, pull the limb and shoulder cranially or caudally; to draw the scapula against the trunk.

Back 115

M. rhomboideus

Front 116

_________ is an epaxial muscle that is completely divided into cranial and caudal parts with different innervation and function

Back 116

M. serratus dorsalis

Front 117

Action: To lift the ribs for inspiration.

Back 117

M. serratus dorsalis cranialis

Front 118

_______________ or expiratory part, consists of three rather distinctly isolated portions.

Back 118

M. serratus dorsalis caudalis

Front 119

Action: To draw the last three or four ribs caudally for expiration.

Back 119

M. serratus dorsalis caudalis

Front 120

Erector spinae muscles (m. erector spinae) These are represented by the various divisions of the _______

Back 120

iliocostalis, longissimus, and spinalis muscles.

Front 121

_________ are the dorsal muscles that include the epaxial muscles located on the dorsal surface of the vertebral column and ribs.

Back 121

Erector spinae muscles (m. erector spinae)

Front 122

Action: Fixation of the vertebral column or lateral movement when only one side contracts; aids in expiration by pulling the ribs caudally.

Back 122

Iliocostalis muscles (m. iliocostalis)

Front 123

Action: For the thoracolumbar portion of the longissimus muscles, extension of the vertebral column.

Back 123

Longissimus muscle (m. longissimus)

Front 124

___________ is a medial epaxial muscle mass composed of a number of different systems of fascicles that join one or more vertebra

Back 124

Transversospinalis muscle

Front 125

The three muscle groups that compose the transversospinalis muscle are the _____________

Back 125

semispinalis,

multifidus, and rotators.

Front 126

are deep segments split off from the longissimus system.

Back 126

Intertransverse Muscles

Front 127

Intertransverse Muscles

Back 127

mm. intertransversarii

Front 128

Interspinal Muscles

Back 128

mm. interspinales

Front 129

Action: Fixation of the vertebral column.

Back 129

Interspinal Muscles

Front 130

The spaces between the ribs are filled by the _____________, which appear in a double layer, internal and external, and cross each other.

Back 130

mm. intercostales

Front 131

Each ____________ is adjacent to m. levatorcostarum dorsally.

Back 131

m. intercostalis externus

Front 132

Cranially, on the thorax, the _________ covers the superficial ventral ends of the first ribs

Back 132

m. rectus thoracis

Front 133

the _________ thoracis crosses the internal surface of the cartilages of the sternal ribs and the sternum.

Back 133

m. transversus

Front 134

___________ are special muscles of the last rib.

Back 134

mm. retractor costae and subcostalis

Front 135

Action: Inspiration; draws the ribs together so as to enlarge the thoracic cavity.

Back 135

mm. intercostales externi

Front 136

Action: Inspiration; the fixed point is the transverse process of the vertebra.

Back 136

mm. levatores costarum

Front 137

Action: Expiration, to draw the ribs together so as to narrow the thoracic cavity

Back 137

mm. intercostales interni

Front 138

___________ located medial to the internal intercostal muscles at the vertebral ends of the caudal ribs, especially ribs 9 to 11.

Back 138

mm. subcostales

Front 139

Action: Inspiration.

Back 139

m. rectus thoracis

Front 140

It bridges the space between the transverse processes of the first three or four lumbar vertebrae and the last rib

Back 140

m. retractor costae

Front 141

sometimes referred to as the triangularis sterni or the sternocostalis internus.

Back 141

m. transversus thoracis

Front 142

Action: The m. transversus thoracis contributes to expiration

Back 142

m. transversus thoracis

Front 143

__________ is a musculotendinous plate between the thoracic and the abdominal cavities. It projects cranially into the thoracic cavity like a dome.

Back 143

Diaphragm

Front 144

From external to internal the _____________ are the rectus abdominis, the obliquus externus abdominis, the obliquus internus abdominis, the transversus abdominis, and quadratus lumborum.

Back 144

abdominal muscles

Front 145

The _____________ extends longitudinally in the ventral abdominal wall on each side of the linea alba from the external surface of the thorax to the pecten ossis pubis.

Back 145

m. rectus abdominis

Front 146

__________ is an expansive sheet covering the ventral half of the lateral thoracic wall and the lateral and ventral parts of the abdominal

Back 146

M. obliquus externus abdominis

Front 147

Action:Along with other abdominal muscles, compression of the abdominal viscera. This action, known as abdominal press, aids in such vital functions as expiration, urination, defecation, and parturition. Flexion of the vertebral column when fellow muscles contract. Lateral bending (lateral flexion) of the vertebral column.

Back 147

M. obliquus externus abdominis

Front 148

Action: Compression and support of the abdominal viscera.

Back 148

M. obliquus internus abdominis

Front 149

_____________ is the deepest abdominal muscle and, like the oblique muscles, it is developed into an extensive leaf that reaches a thickness of 2 to 4 mm in large dogs

Back 149

M. transversus abdominis

Front 150

__________ covers the inner surfaces of the mm. transversi abdominis

Back 150

Transversalis fascia

Front 151

________ is a long, flat, relatively narrow (compared with the other abdominal muscles) muscle that extends from the first costal cartilage to the pecten ossis pubis

Back 151

M. rectus abdominis

Front 152

Action: All functions that depend on abdominal press, such as expiration, urination, defecation, and parturition; support of the abdominal viscera; to bring the pelvis cranial; flexion of the trunk

Back 152

M. rectus abdominis

Front 153

The __________ is amidventral strip of collagenous tissue that extends from the xiphoid process to the symphysis pelvis

Back 153

linea alba

Front 154

Action: shakes the skin to remove foreign bodies and increase heat production. It also tenses the skin when required.

Back 154

M. cutaneus trunci

Front 155

Action: draws the prepuce over the glans after erection.

Back 155

M. preputialis

Front 156

__________ aids in support of the mammary glands and perhaps in milk ejection.

Back 156

M. supramammaricus

Front 157

dorsal in location, are extensors or levators of the tail.

Back 157

mm. sacrocaudalis dorsalis lateralis and medialis

Front 158

ventral in location, are flexors or depressors of the tail.

Back 158

mm. sacrocaudalis ventralis lateralis and medialis,

Front 159

lateral in location, are the lateral flexors of the tail.

Back 159

mm. coccygeus, levator ani, and the intertransversariicaudae

Front 160

__________ in quadrupedal mammals is the vertical closure of the pelvic cavity through which the rectum passes.

Back 160

Pelvic diaphragm (diaphragma pelvis)

Front 161

The two muscles of the pelvic diaphragm are the _______ & ________

Back 161

m. coccygeus and the m. levator ani.