Download Chapter 11, Part 1 Muscles of the head and Neck

Chapter 11, Part 2
Muscles of the head and Neck
Fig. 11.2b
Epicranial
aponeurosis
Epicranius
Frontal belly
of occipitofrontalis
Occipital belly
of occipitofrontalis
Orbicularis oculi
Levator labii superioris
Zygomaticus minor
Levator anguli oris
Zygomaticus major
Buccinator
Orbicularis oris
Sternocleidomastoid
Mentalis
Depressor labii inferioris
Depressor anguli oris
Platysma
© The McGraw-Hill Companies, Inc./Photos and Dissections by Christine Eckel
Copyright © McGraw-Hill Education. Permission required for reproduction or display.
Fig. 11.4
Extrinsic Eye Muscles
(a) Lateral view, right eye
Superior
oblique
Frontal bone
Superior rectus
Common tendinous ring
Trochlea
Optic nerve
Lateral rectus
Orbicularis
oculi
• AKA extraocular muscles
• called extrinsic because
originate in orbit and
insert into sclera of eye
• Move the eyes
• Rectus eye muscles
originate from common
tendinous ring
Inferior rectus
Maxilla Inferior oblique
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(a) Lateral view, right eye
Extrinsic Eye Muscles
• Lateral rectus
• attaches to anterolateral surface of eye
• pulls eye laterally (toward ear)
Superior rectus
• Inferior rectus
• attaches to anteroinferior surface of eye
• pulls eye down and medially (look at tip of
nose)
Lateral rectus
Inferior rectus
• Superior rectus
• attaches to anterosuperior surface of eye
• pulls eye up and medially (look at procerus
muscle)
Copyright © McGraw-Hill Education. Permission required for reproduction or display.
Fig. 11.4
(b) Medial view, right eye
Extrinsic Eye Muscles
• Medial rectus
• attaches to anteromedial surface of
eye
• pulls eye medially (toward bridge of
nose)
Superior rectus
Medial rectus
Optic nerve
Common tendinous ring
Inferior rectus
Fig. 11.4
(a) Lateral view, right eye
Extrinsic Eye Muscles
Superior
oblique
Trochlea
• Oblique eye muscles
• originate from within the orbit
• inserts on posterolateral part of eye
• Superior oblique
• hooks through trochlea
• inserts on posterior superior part of eye
• pulls back of eye up (eye looks down)
• Inferior oblique
• inserts on posterior inferior part of eye
• pulls back of eye down (eye looks up)
Inferior oblique
Copyright © McGraw-Hill Education. Permission required for reproduction or display.
Fig. 11.4
(b) Medial view, right eye
(a) Lateral view, right eye
Superior
oblique
Frontal bone
Superior rectus
Common tendinous ring
Trochlea
Orbicularis
oculi
Trochlea
Superior rectus
Superior oblique
Medial rectus
Optic nerve
Optic nerve
Lateral rectus
Inferior rectus
Inferior oblique
Common tendinous ring
Inferior rectus
Maxilla Inferior oblique
Trochlea
Superior rectus
Sagittal axis
Coronal axis
Superior oblique
Lateral rectus
Optic canal
Common tendinous ring
Inferior oblique
Inferior rectus
Medial rectus
(c) Anterior view of right orbit, eye removed
Trochlea Center of eye
Inferior oblique
Superior oblique
Medial rectus
Inferior Lateral
(d) Superior view
Superior
rectus rectus
rectus Copyright © McGraw-Hill Education. Permission required for reproduction or display.
Fig. 11.5
Muscles of Mastication
(superficial)
Temporalis
• Buccinator is deep to masseter
• prevents “chipmunk cheeks”
• Masseter connects zygomatic process to mandible
• elevates and protracts mandible
• most powerful chewing muscle
• Orbicularis oris is ring around mouth
• “puckers up”
Buccinator
Masseter
Orbicularis
oris
(a) Superficial lateral view
• Temporalis extends from temporal lines on parietal
and frontal bones to coronoid process of mandible
(deep to zygomatic process)
• elevates and retracts mandible
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Fig. 11.6
Muscles that Move the Tongue
• Intrinsic muscles curl,
squeeze and fold tongue
• sit inside tongue
• tongue acts like muscle, but
actually isn’t
• Extrinsic muscles have
origin on other head and
neck structures, insert on
tongue
Palatoglossus
Styloid
process
Tongue
Styloglossus
Genioglossus
Mandible (cut)
Hyoid bone
Hyoglossus
• end in -glossus
Right lateral view
Thyroid cartilage
Fig. 11.6
Muscles that Move the Tongue
(extrinsic)
• genioglossus muscles (left/right)
• originate on mandible
• protract tongue
Styloid
process
Tongue
Genioglossus
Mandible (cut)
Hyoid bone
Styloglossus
Thyroid cartilage
Right lateral view
Fig. 11.6
Muscles that Move the Tongue
(extrinsic)
• genioglossus muscles (left/right)
• originate on mandible
• protract tongue
Styloid
process
Tongue
Styloglossus
Genioglossus
Mandible (cut)
Hyoid bone
• styloglossus muscles (left/right)
• originate on styloid process of temporal
bone
• elevate and retract tongue
Thyroid cartilage
Right lateral view
Fig. 11.6
Muscles that Move the Tongue
(extrinsic)
Palatoglossus
• hyoglossus muscles (left/right)
• originate on hyoid bone
• insert on sides of tongue
• depress and retract tongue
Tongue
Styloglossus
Genioglossus
Mandible (cut)
Hyoid bone
Hyoglossus
• palatoglossus muscles (left/right)
• originate on soft palate
• elevate posterior portion of tongue
Thyroid cartilage
Right lateral view
Fig. 11.6
Muscles of the Pharynx
• pharynx is funnel-shaped tube
Styloid
behind and below mouth and nose
process
• pharyngeal constrictor muscles
contract sequentially to swallow
food
pharyngeal
Tongue
Mandible (cut)
constrictor
muscles
Hyoid bone
Thyroid cartilage
Right lateral view
Fig. 11.6
Muscles of the Anterior Neck
• Suprahyoid muscles are above the
hyoid bone
• elevate hyoid during swallowing or
speaking
• Stylohyoid muscle
• Geniohyoid muscle
• Mylohyoid
Styloid
process
Tongue
Stylohyoid
Mandible (cut)
Geniohyoid
Hyoid bone
Thyroid cartilage
Right lateral view
Fig. 11.8
Superficial
Anterior Neck
• Digastric: two bellies
• anterior belly from mental
protuberance to hyoid
• posterior belly from hyoid to
mastoid portion of temporal
bone
• depresses mandible, elevates
hyoid
Digastric:
Anterior belly
Posterior belly
Sternocleidomastoid
Trapezius
Fig. 11.8
Superficial
Anterior Neck
• Infrahyoid muscles
• Depress hyoid bone
•
•
•
•
Omohyoid
Sternohyoid
Thyrohyoid
Sternothyroid
Omohyoid
Sternohyoid
Fig. 11.9
Stylohyoid
Posterior belly of digastric
Semispinalis capitis
Splenius capitis
Levator scapulae
Mylohyoid
Anterior belly of digastric
Thyrohyoid
Inferior constrictor
Sternothyroid
Superior belly of omohyoid
Sternohyoid
Sternocleidomastoid
Scalene muscles
Trapezius
Inferior belly of omohyoid
Platysma (cut)
Anterolateral view
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Fig. 11.9
Muscles that Move the
Head and Neck
• Anterolateral neck muscles flex the
neck
• Sternocleidomastoid
• Originates on sternum and clavicle
• Inserts on mastoid process of temporal
bone
• Contraction of both flexes the neck
• Contraction of one rotates head to
opposite side and laterally flexes neck
Sternocleidomastoid
Scalene muscles
Trapezius
Inferior belly of
omohyoid
Anterolateral view
Platysma (cut)
Copyright © McGraw-Hill Education. Permission required for reproduction or display.
Fig. 11.9
Muscles that Move the
Head and Neck
• Anterolateral neck muscles flex the
neck
• Scalene muscles (anterior, middle,
and posterior)
• Originate from transverse processes of
C2 to C7
• Insert onto ribs 1 and 2
• Elevate ribs 1 and 2 during inhalation
Sternocleidomastoid
Scalene muscles
Trapezius
Inferior belly of
omohyoid
Anterolateral view
Platysma (cut)
Copyright © McGraw-Hill Education. Permission required for reproduction or display.
Fig. 11.9
Muscles that Move the
Head and Neck
• Trapezius
• Superior fibers support neck
• Originate on occipital protuberance
(occipital bone) and spinous processes
of C7 to T12
• Insert on clavicle and scapula
• Pulls down on back of head
Sternocleidomastoid
Scalene muscles
Trapezius
Inferior belly of
omohyoid
Anterolateral view
Platysma (cut)
Fig. 11.11
Muscles of the
Vertebral Column
Deeper
Deep
Longissimus
capitis
Splenius
capitis
Serratus posterior superior
External intercostals
Splenius cervicis
Iliocostalis group
Longissimus group
Erector spinae
Spinalis group
• Complex origins and
insertions
• Extensive overlap
• Covered by superficial
back muscles (trapezius
and lattisimus dorsi)
Semispinalis
capitis
Semispinalis
cervicis
Transversospinalis
Semispinalis
thoracis
Serratus posterior inferior
Multifidus
Internal
oblique
Quadratus lumborum
External
oblique (cut)
Posterior view
Fig. 11.11
Muscles of the Vertebral Column
• Erector spinae
• group of muscles that maintain
posture
• iliocostalis group
• most laterally placed
• longissimus group
Erector
spinae
Deep
Iliocostalis group
Longissimus group
Spinalis group
• inserts on transverse processes of
vertebrae
• spinalis group
• most medially placed
• insert on spinous processes of
vertebrae
Posterior view
Fig. 11.11
Muscles of the Vertebral Column
• Transversospinalis
• connect and stabilize vertebrae
• includes semispinalis capitis, semispinalis cervicis
• semispinalis thoracis extends and laterally flexes
vertebral column
• multifidus extends and rotates vertebral column
• rotatores thoracis extends and rotates vertebral
column
Posterior view
Deeper
Semispinalis
capitis
Semispinalis
cervicis
TransversoSemispinalis spinalis
thoracis
Multifidus
Rotatores thoracis
Transverse process
of vertebra
Spinous process
of vertebra
Fig. 11.11
Deeper
Muscles of the Vertebral Column
• Quadratus lumborum
• located primarily in lumbar region
• bilateral contraction extends
vertebral column
• unilateral contraction flexes vertebral
column laterally
Quadratus lumborum
Posterior view
Fig. 11.13
Muscles of Respiration
• Muscles contract to
increase volume of lungs,
drawing air in (inhalation)
• On exhalation, most
muscles relax, some
contract to decrease
volume of lungs, forcing air
out
• respiration muscles are on
anterior and posterior
surfaces of thorax, deep to
trapezius and latissimus
dorsi, superficial to erector
spinae muscles
Scalene muscles
External
intercostals
Internal intercostals
Transversus thoracis
Diaphragm
(a) Anterior view
Fig. 11.13
Muscles of Respiration
• external intercostals extend
from superior rib to adjacent
External
inferior rib
intercostals
• lift rib on inhalation
• internal intercostals lie deep to
external intercostals
Scalene muscles
Internal intercostals
Transversus thoracis
• fibers at right angles to external
intercostals
• depress ribs on exhalation
Diaphragm
(a) Anterior view
Fig. 11.13
Muscles of Respiration
• serratus posterior superior attaches to ribs
2-5; elevates them in inhalation
• serratus posterior inferior attaches to ribs
8-12; depresses them during exhalation
Fig. 11.13
Muscles of Respiration
• transverse thoracis extends across inner
surface of rib cage, inserts on ribs 2-6
Scalene muscles
• depresses ribs
Transversus thoracis
Diaphragm
(a) Anterior view
(a) Interior view
Fig. 11.13
Muscles of Respiration
• diaphragm is sheet of muscle that separates
thoracic cavity from abdominal cavity
• aponeurosis in center is insertion point
• contraction of diaphragm pulls diaphragm down,
increasing size of thoracic cavity
Diaphragm
(a) Anterior view
Fig. 11.13
Muscles of Respiration
• diaphragm is sheet of muscle that separates
thoracic cavity from abdominal cavity
• aponeurosis in center is insertion point
• contraction of diaphragm pulls diaphragm down,
increasing size of thoracic cavity
Fig. 11.13
Muscles of Respiration
• diaphragm is sheet of muscle that
separates thoracic cavity from
abdominal cavity
• aponeurosis in center is insertion point
(central tendon)
• contraction of diaphragm pulls diaphragm
down, increasing size of thoracic cavity
(a) Diaphragm, inferior view
Sternum
Xiphoid process
Costal cartilage
Central tendon
of diaphragm
Caval opening
Aortic opening
(hiatus) 12th rib
Right crus
Esophageal
opening
Left crus
L2
L3
L4
Quadratus lumborum
muscle (cut)
Psoas major
muscle (cut)
Fig. 11.13
Muscles of the Abdominal Wall
• muscles compact and
hold in the abdominal
organs
• work together to flex
and stabilize vertebral
column
• unilateral contraction
laterally flexes
vertebral column
Fig. 11.13
Muscles of the Abdominal Wall
• rectus abdominis
• long, runs vertically entire length of
abdominal wall from pubis (origin) to
sternum (insertion)
• four segments created by three tendinous
intersections (form “six pack”)
• enclosed in rectus sheath made by
• aponeurosis of external oblique
• internal oblique
• transversus obdominis
• Medial border of rectus sheaths is fibrous
strip called linea alba
Linea alba
Rectus sheath
Tendinous intersection
Rectus abdominis
Muscles of the Abdominal Wall
• external oblique
• most superficial of abdominal muscles
• two groups of muscles connected by
Transversus abdominis
aponeurosis
Internal obliques
• inguinal ligament extends from
External obliques
anterior superior iliac spine to public
tubercle along bottom of aponeurosis
• fibers run from superior lateral to
inferior medial
Fig. 11.13
Muscles of the Abdominal Wall
• internal oblique
• deep to external oblique
• forms aponeurosis medially
• fibers run from inferior lateral to
superior medial
• rotates vertebral column
• transversus obdominis
• deep to internal oblique
• fibers run laterally
Transversus abdominis
Internal obliques
External obliques
Fig. 11.13
Muscles of the Pelvic Floor
• Pelvic diaphragm = 3 layers of
muscles and fasciae
• Extends from ischium and pubis to
sacrum and coccyx
• Support pelvic viscera