Transcript Chapter 11 Muscles

Chapter 11 Muscles
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Muscles of facial expression
Muscles of mastication
Extrinsic tongue muscles
Muscles of the neck and throat
Back muscles
Deep thorax muscles
Abdominal wall muscles
Superficial thorax muscles
Shoulder muscles
Elbow muscles
Forearm muscles
Hip & knee muscles
Leg muscles
Chapter 11 Muscles
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You are responsible for muscles described in
class
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Origin
Insertion
Action
Nerve - innervation (if given)
Be able to recognize muscles in all diagrams of
text
Muscles of facial expression
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Orbicularis oculi
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Sphincter muscle of eyelid
O: frontal & maxillary bones
I: tissue of eyelid
Action: closes eye
Nerve: facial / CN VII
(11.6)
Muscles of facial expression
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Zygomaticus
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O: zygomatic bone
I: corners of mouth
Action: smiling
Nerve: facial / CN VII
(11.6)
Muscles of mastication
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Masseter
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O: zygomatic arch
I: angle & ramus of
mandible
Action: elevate mandible
Nerve: trigeminal nerve /
CN V (foramen ovale)
Masseter
(11.7a)
Muscles of mastication
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Temporalis
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O: temporal fossa
I: coronoid process of
mandible
Action: elevate and
retract mandible
Nerve: trigeminal n. /
CN V
(11.7a)
Extrinsic tongue muscles
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Styloglossus
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O: styloid process of
temporal bone
I: tongue
Action: retract & elevate
tongue
Nerve: hypoglossal n. /
CN XII
Styloglossus
(11.7c)
Extrinsic tongue muscles
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Hyoglossus
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O: hyoid bone
I: tongue
Action: depresses tongue
Nerve: hypoglossal n. /
CN XII
Hyoid bone
(11.7c)
Muscles of neck & throat
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Digastric
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two muscle bellies with an
intermediate tendon attached to
the hyoid bone
O: inferior margin of mandible
(anterior belly); mastoid process
of temporal bone (posterior belly)
I: hyoid bone
Action: elevate hyoid, stabilize
hyoid, depress mandible
Nerve: trigeminal n. / CN V
(anterior belly), facial n. / CN VII
(posterior belly)
Anterior belly
(11.8a)
Posterior belly
Muscles of neck & throat
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Stylohyoid
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O: styloid process of
temporal bone
I: hyoid bone
Action: elevate & retract
hyoid, swallow
Nerve: facial n. / CN VII
Stylohyoid
(11.7c)
Muscles of neck & throat
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Sternohyoid
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O: manubrium &
medial end of clavicle
I: hyoid bone
Action: depress hyoid
Sternohyoid
(11.8a)
Muscles of neck & throat
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Pharyngeal constrictors
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O: mandible, pterygoid
process, hyoid, laryngeal
cartilages
I: posterior medial raphe of
pharynx
Action: peristaltic
contraction / swallow
Superior
Middle
Inferior
(11.8b)
Muscles of neck & throat
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Sternocleidomastoid
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O: manubrium & medial
clavicle
I: mastoid process of
temporal bone
Action: head & neck
flexion, rotate head
contralaterally
Nerve: accessory n. /
CN XI
(11.8a)
Muscles of neck & throat
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Sternocleidomastoid
Back muscles
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Spinalis
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O: spines of upper
lumbar and lower
thoracic vertebrae
I: spines of upper
thoracic and cervical
vertebrae
Action: extends
vertebral column
(11.9d)
Deep thorax muscles
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External & internal
intercostals
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O&I: inferior & superior
border of ribs
Action: inspiration and
expiration
Internal
(11.10a)
Deep thorax muscles
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Diaphragm
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O: inferior internal
surface of rib cage &
sternum, inferior costal
cartilages, lumbar
vertebrae
I: central tendon
Action: flattens on
contraction (inspiration)
Nerve: phrenic nerves
Xiphoid process
(11.10b)
Abdominal wall
muscles
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Rectus abdominis
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O: pubic crest & symphysis
I: xiphoid process and
costal cartilages of ribs 5-7
Action: flex & rotate lumbar
vertebrae, fix & depress
ribs, stabilize pelvis during
walking, increase
intraabdominal pressure
Note: 3 tendinous
insertions, aponeurosis &
linea alba
(11.11ab)
Superficial thorax muscles
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Pectoralis minor
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O: anterior surface of
ribs 3-5
I: coracoid process of
scapula
Action: with ribs fixed,
pulls scapula anterior &
inferior; with scapula
fixed, pulls ribs
superiorly
Nerve: Medial and
lateral pectoral nerves
(C6-C8)
(11.13a)
Superficial thorax muscles
Superificial
thorax muscles
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Serratus anterior
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O: ribs 1-8
I: vertebral border of
scapula
Action: hold scapula
against chest wall, moves
inferior angle of scapula
lateral & superior
(abduction, pushing,
punching)
Nerve: long thoracic nerve
(11.13a,8.1a reversed)
Superificial thorax
muscles
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Trapezius
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O: occipital bone,
ligamentum nuchae, C7T12 spinous processes
I: acromion, spine of
scapula, lateral third of
clavicle
Action: stabilize, elevate,
adduct, depress scapula,
extend head
Nerve: Accessory
(CNXI), C3 and C4
(11.13b)
Shoulder muscles
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Pectoralis major
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O: medial clavicle,
sternum, cartilage of
ribs 1-6, aponeurosis
of external oblique
I: greater tubercle of
humerus
Action: arm-flexion,
medial rotation,
adduction, elevation
of rib cage
(11.13a)
-Nerve: Medial and lateral
pectoral nerves (C6-C8)
Shoulder muscles
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Deltoid
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O: lateral clavicle,
acromion & spine of
scapula (compare to
insertion of trapezius)
I: deltoid tuberosity of
humerus
Action: arm-abduction,
flexion, extension, medial
& lateral rotation
Nerve: Axillary nerve(C5C-6)
(11.13ab)
Shoulder muscles
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Subscapularis
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O: subscapular fossa
I: lesser tubercle of
humerus
Action: medial rotate
arm, stabilize shoulder
joint
Nerve: Subscapular
nerves (C5-C7)
(11.14d)
Shoulder muscles
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Infraspinatus
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O: infraspinous fossa
I: greater tubercle of
humerus
Action: lateral rotate
humerus, stabilized
shoulder joint
Nerve: Suprascapular
nerve
(11.14b)
Rotator cuff muscles
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Act to stabilize head of humerus in glenoid
cavity and prevent dislocation
Supraspinatous
(Suprascapular nerve)
Infraspinatus
(Suprascapular nerve)
Subscapularis
(Subscapular nerve)
Teres minor
(Axillary nerve)
Elbow muscles
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Triceps brachii
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O: long headinfraglenoid
tubercle, lat. & med.
heads-posterior
shaft of humerus
I: olecranon process
of ulna
Action: extend
forearm, assist
adduction of arm
Nerve: Radial nerve
(11.14b)
Elbow muscles
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Biceps brachii
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O: short head-coracoid
process, long head-tubercle
above glenoid cavity and lip of
glenoid cavity (intertubercular
groove)
I: radial tuberosity
Action: flex elbow, supinate
forearm, weak arm flexor
Nerve: Musculocutaneous
nerve (C5 & C6)
(11.14c)
Forearm muscles
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Flexor carpi (radialis
& ulnaris)
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O: medial epicondyle
of humerus, ulna
I: metacarpals and
carpals
Action: wrist flexion,
abduct & adduct hand
Carpal tunnel (Median
nerve) syndrome p.
184
radialis
ulnaris
(11.15a)
Anterior view
Forearm muscles
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Extensor carpi
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O: lateral epicondyle of
humerus
I: base of metacarpals
Action: extend, abduct,
and adducts wrist
Palpate forearm muscles
Hip & knee muscles
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Quadriceps femoris
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O: anterior inferior iliac
spine, superior margin of
acetabulum, greater
trochanter, shaft of femur
I: patella and tibial
tuberosity via patellar
tendon
Action: extend knee, flex
thigh
Hip & knee muscles
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Gluteus muscles
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O: ilium, sacrum, coccyx
I: shaft & greater
trochanter of femur
Action: extend thigh (climb
stairs, running), lateral &
medial rotate thigh, abduct
thigh, steadies pelvis
Hip & knee muscles
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Hamstrings
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O: ischial tuberosity, shaft
of femur
I: lateral & medial
condyles and shaft of
tibia, head of fibula, lateral
condyle femur
Action: extend thigh, flex
knee
Makes touching toes hard
Leg muscles
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Tibialis anterior
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O: lateral condyle and
shaft of tibia
I: tarsal and first
metatarsal bones
Action: dorsiflexion
Leg muscles
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Gastrocnemius
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O: medial & lateral
condyles of femur
I: calcaneus via Achilles
tendon
Action: plantar flexion, flex
knee