Muscle Action

Front 1

To draw the commisure of the lips caudally

Back 1

Platysma

Front 2

To close the mouth. It pulls the nose downward (sniffing)

Back 2

Orbicularis Oris

Front 3

Extend and dilate the ext. nares

Back 3

Incisivus Superioris et Inferioris

Front 4

Increase the diameter of ext. nares and lift the apical portion of the upper lip

Back 4

Maxillonasolabial (Nasal part)

Caninus (Labial part)

Front 5

To return the food from the vestibule to masticatory surface of the tooth

Back 5

Buccinator

1. pars buccalis (pars dorsalis)

2. para molaris (pars ventralis)

Front 6

Stiffen the lower lip in apical region

Back 6

Mentalis

Front 7

Fix the angle of the mouth and draws it back

Back 7

Zygomaticus

Front 8

Fix and pull the scutulum forward

Back 8

Frontalis

Front 9

Close the palpebral fissure

Back 9

Orbicularis Oculi

Front 10

To lift the upper lid

Back 10

Levator Palpebrae Superioris (main retractor of the eyelid)

Front 11

To draw the lateral palpebral angle caudally

Back 11

Retractor Anguli Oculi Lateralis

Front 12

Lift the upper lid, erect the hair of eyebrow

Back 12

Levator Anguli Oculi Medialis

Front 13

Increases the diameter of nose and lift the apical portion of the upper lid

Back 13

Levator Nasolabialis

Front 14

Open the jaws

Back 14

Digastricus (Biventer mandibularis)

Front 15

To raise the basihyoid bone

Back 15

Stylohyoideus (Absent in beagles)

Front 16

To rotate the eyeball

Back 16

Obliquus Ventralis

Front 17

To rotate the eyeball

Back 17

Obliquus Dorsalis or Trochlearis

Front 18

Rotates the eyeball on vertical axis

Back 18

Rectus Dorsalis

Rectus Lateralis

Front 19

Rotates the eyeball horizontally

Back 19

Rectus Medialis

Rectus Ventralis

Front 20

To retract the eyeball; aids in bringing the oblique eye movement

Back 20

Retractor Bulbi

Front 21

to raise the mandible in closing the mouth

Back 21

masseter

Front 22

to raise the mandible in closing the mouth

Back 22

temporalis

Front 23

to raise the mandible

Back 23

Pterygoideus Lateralis

Front 24

To raise the mandible

Back 24

Pterygoideus Medialis

Front 25

fixation of the vertebral column, lateral movement when only 1 side contracts

Back 25

iliocostalis lumborum

Front 26

expiration by pulling the ribs caudally

Back 26

iliocostalis thoracis

Front 27

extend the vert. column; raising the cranial portion of the body from the pelvis, sacrum and loin

Back 27

longissimus thoracis et lumborum

Front 28

fixation of vert. column (cervicothoracic junction)

Back 28

longissimus lumborum

Front 29

extend the neck

Back 29

longissimus thoracis

Front 30

extend the neck

Back 30

longissimus cervicis

Front 31

extension of the atlanto-occipital joint; rotates the atlantoaxial joint; fixes the atlantoaxial joint

Back 31

longissimus capitis et atlantis

Front 32

to raise the head and neck and to flex head and neck

Back 32

complexus

Front 33

fix the thoracic vert. and raise the nexk

Back 33

spinalis et semi spinalis thoracis

Front 34

fix the thoracic vert. and raise the neck

Back 34

spinalis cervicis

Front 35

fixes the vert. column; and bilateral action of the back

Back 35

multifidus cervicis

Front 36

fixes the vert. column; and, bilateral action of the back

Back 36

multifidus luborum

Front 37

fixes the vert. column; and bilateral action of the back

Back 37

multifidus thoracis