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10
The Muscular
System
PowerPoint® Lecture Presentations prepared by
Alexander G. Cheroske
Mesa Community College at Red Mountain
© 2011 Pearson Education, Inc.
Section 1: Functional Organization of the
Muscular System
• Learning Outcomes
• 10.1 Describe the arrangement of fascicles in the
various types of muscles, explain the resulting
functional differences, and explain how different
classes of levers affect muscle efficiency.
• 10.2 Explain how the name of a muscle can help
identify its location, appearance, or function.
• 10.3 Describe the separation of muscles into axial
and appendicular divisions.
© 2011 Pearson Education, Inc.
Section 1: Functional Organization of the
Muscular System
• Muscular system
• Accounts for almost half body weight
• Contains ~700 muscles
• Vary widely in size, shape, and function
• Performance varies on how fibers are organized
and how muscle attaches to skeleton
• Divided into two divisions
1. Axial muscles
•
Support and position axial skeleton
2. Appendicular muscles
•
Support, move, and brace the limbs
© 2011 Pearson Education, Inc.
The two divisions of the muscular system:
axial muscles and appendicular muscles
The proportion of total body weight contributed by the muscular system
Urinary system 0.7%
Respiratory system 1.7%
Nervous system 2%
Digestive system 6%
Integumentary
system
16%
Lymphatic system 0.3%
Reproductive system 0.15%
Endocrine system 0.15%
Cardiovascular system 9%
Axial
muscles
Skeletal
system
20%
Muscular system
44%
Tendons conduct the
forces of contraction to
perform specific tasks.
Appendicular
muscles
Figure 10 Section 1
© 2011 Pearson Education, Inc.
Module 10.1: Fascicle organization and range
of motion
• Fascicle organization
• Parallel muscle
• Fascicles parallel to muscle long axis
• Most skeletal muscles in the body are parallel
• Some flat with broad attachments (aponeuroses)
• Some plump and cylindrical with tendon attachments
• Has central body (belly)
• Can contract until shortened by ~30%
• Due to muscle fiber shortening
• Example: biceps brachii
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A parallel muscle:
the biceps brachii
(1)
Fascicle
Body
(belly)
1
Figure 10.1
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1
Module 10.1: Fascicle organization and range
of motion
• Fascicle organization (continued)
• Convergent muscle
• Fascicles extending over broad area converge on
common attachment site
• Versatile action
• Different portions can contract to produce different actions
• Entire muscle can contract
• Pulls less on attachment compared to parallel
• Example: pectoralis major
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A convergent muscle:
the pectoralis major
(2)
Base of
muscle
Tendon
2
Figure 10.1
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2
Module 10.1: Fascicle organization and range
of motion
• Fascicle organization (continued)
• Pennate muscle (penna, feather)
• Fascicles form common angle with tendon
• Pull at an angle on tendon
• Shorter movement of tendon versus parallel
• Contain more fibers than parallel of same size so
produces more tension
© 2011 Pearson Education, Inc.
Module 10.1: Fascicle organization and range
of motion
• Fascicle organization (continued)
• Pennate muscle (continued)
• Three types
1. Unipennate (all fibers on one side of tendon)
•
Example: extensor digitorum
2. Bipennate (fibers insert on both sides of tendon)
•
Example: rectus femoris
3. Multipennate (tendon branches within pennate muscle)
•
© 2011 Pearson Education, Inc.
Example: deltoid
Three pennate muscles
Extensor digitorum muscle
Rectus femoris muscle
Deltoid muscle
(3c)
(3a)
Tendons
3
Extended
tendon
If all the muscle fibers are
on the same side of the
tendon, the pennate
muscle is unipennate.
If a pennate muscle
has fibers on both
sides of the tendon, it
is called bipennate.
(3b)
If the tendon branches within a
pennate muscle, the muscle is
said to be multipennate.
Figure 10.1
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3
A circular muscle, or sphincter
(4)
4
Contracted
Relaxed
Figure 10.1
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4
Module 10.1: Fascicle organization and range
of motion
• Levers and Leverage
• Skeletal muscle force, speed, and direction depend
on how it is attached to a lever
• Lever moves when applied force overcomes load
• Lever = rigid structure (bone)
• Fulcrum = fixed point on which lever pivots (joint)
• Applied force = muscle action
Animation: Classes of Levers
© 2011 Pearson Education, Inc.
Module 10.1: Fascicle organization and range
of motion
• Levers and Leverage (continued)
• Lever classes
1. First-class lever
•
Fulcrum (F) between applied force (AF) and load (L)
•
Acts like seesaw
•
•
Balance depends on sizes of force and load and
distribution on lever
Few examples in body but important
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A first-class lever
Load
Fulcrum
Applied
force
Figure 10.1
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5
Module 10.1: Fascicle organization and range
of motion
• Levers and Leverage (continued)
• Lever classes (continued)
2. Second-class lever
•
Load is between applied force and fulcrum
•
•
Always farther from fulcrum than load so small force
moves large load, but slowly and short distance
Acts like wheelbarrow
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A second-class lever
Load
Fulcrum
Applied
force
Figure 10.1
© 2011 Pearson Education, Inc.
6
Module 10.1: Fascicle organization and range
of motion
• Levers and Leverage (continued)
• Lever classes (continued)
3. Third-class lever
•
Most common lever in body
•
Force applied between load and fulcrum
•
Speed and distance traveled increased at expense of
effective force
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A third-class lever
Applied
force
Load
Biceps brachii
muscle
Fulcrum
Figure 10.1
© 2011 Pearson Education, Inc.
7
Module 10.1 Review
a. Define a lever, and describe the three classes
of levers.
b. The joint between the occipital bone of the
skull and the first cervical vertebra (atlas) is
which part of which class of lever system?
c. Why does a pennate muscle generate more
tension than does a parallel muscle of the
same size?
© 2011 Pearson Education, Inc.
Module 10.2: Muscle names
•
Individual muscle parts
•
Origin
•
Fixed attachment
•
Most are bones, some are connective tissue
sheaths or bands (examples: intermuscular septa
or interosseus membranes)
•
Typically proximal to insertion in anatomical position
•
Insertion
•
•
Movable attachment
Action
•
Specific movement
© 2011 Pearson Education, Inc.
The origins, insertion, and action
of the biceps brachii muscle
Origins of biceps
brachii muscle
Action
Insertion of biceps
brachii muscle
Figure 10.2
© 2011 Pearson Education, Inc.
1
Module 10.2: Muscle names
•
Muscles working together
•
Agonist (prime mover)
•
Muscle whose contraction chiefly responsible for
producing particular movement
•
Example: biceps brachii is agonist for elbow flexion
•
Synergist (syn-, together + ergon, work)
•
Muscle that helps larger agonist work efficiently
•
May provide additional pull or stabilize origin
•
Example: brachioradialis for elbow flexion
© 2011 Pearson Education, Inc.
Module 10.2: Muscle names
•
Muscles working together (continued)
•
Antagonist
•
Muscle whose action opposes particular
agonist
•
Example: triceps brachii for elbow flexion (to
biceps brachii)
•
Agonist for elbow extension
© 2011 Pearson Education, Inc.
Descriptions of muscles
based on their function
Agonist, or prime mover
Antagonist
Synergist
Insertion of
brachioradialis
muscle
Origin of
brachioradialis
muscle
Figure 10.2
© 2011 Pearson Education, Inc.
2
Module 10.2: Muscle names
• Muscle terminology examples
• Terms indicating specific body regions
• Abdominis (abdomen)
• Anconeus (elbow)
• Auricularis (auricle of ear)
• Brachialis (brachium)
• Terms indicating position, direction of fascicle organization
• Anterior (front)
• Externus (superficial)
• Extrinsic (outside)
• Inferioris (inferior)
© 2011 Pearson Education, Inc.
Module 10.2: Muscle names
• Muscle terminology examples (continued)
• Terms indicating structural characteristics of muscle
• Name of origin
• Biceps (two heads)
• Triceps (three heads)
• Shape
• Deltoid (triangle)
• Orbucularis (circle)
• Other striking features
• Alba (white)
• Brevis (short)
© 2011 Pearson Education, Inc.
Module 10.2: Muscle names
• Muscle terminology examples (continued)
• Terms indicating actions
• General
• Abductor
• Adductor
• Depressor
• Extensor
• Specific
• Buccinator (trumpeter)
• Risorius (laugher)
• Sartorius (like a tailor)
© 2011 Pearson Education, Inc.
Module 10.2 Review
a. Define the term synergist as it relates to
muscle action.
b. Muscle A abducts the humerus, and muscle
B adducts the humerus. What is the
relationship between these two muscles?
c. What does the name flexor carpi radialis
longus tell you about this muscle?
© 2011 Pearson Education, Inc.
Module 10.3: Axial and appendicular divisions
• Axial muscles
• Arise on axial skeleton
• Encompass ~60% of skeletal muscles in body
• Position head and spinal column
• Move rib cage, assist breathing
• Appendicular muscles
• Stabilize or move appendicular skeleton
• Remaining 40% of all skeletal muscles
© 2011 Pearson Education, Inc.
Module 10.3 Review
a. What is the function of the axial muscles?
b. Identify the division (axial or appendicular) to
which each of the following muscles belongs:
biceps brachii, external oblique, temporalis,
and vastus medialis.
c. Which structures labeled in the figures in this
module are not muscles?
© 2011 Pearson Education, Inc.
Section 2: Axial Muscles
• Learning Outcomes
• 10.4 Identify the principal muscles of facial
expressions, along with their origins,
insertions, and actions.
• 10.5 Identify the principal muscles of the eye and
jaw, along with their origins, insertions, and
actions.
• 10.6 Identify the principal muscles of the tongue,
pharynx, and neck, along with their origins,
insertions, and actions.
© 2011 Pearson Education, Inc.
Section 2: Axial Muscles
• Learning Outcomes
• 10.7 Identify the principal muscles of the vertebral
column, along with their origins, insertions,
and actions.
• 10.8 Identify the principal muscles of the trunk,
along with their origins, insertions, and
actions.
• 10.9 Identify the principal muscles of the pelvic
floor, along with their origins, insertions,
and actions.
© 2011 Pearson Education, Inc.
Section 2: Axial Muscles
•
Axial Muscles
•
Involved in stabilizing and positioning head,
neck, and trunk
•
Four groups
1. Muscles of head and neck
2. Muscles of vertebral column
3. Muscles of thoracic and abdominal walls
4. Muscles of pelvic floor
© 2011 Pearson Education, Inc.
The muscles of the head
and neck that are not
associated with
the vertebral column
The muscles of the
vertebral column
The muscles of the pelvic floor
The oblique and
rectus muscles of
the trunk
Figure 10 Section 2
© 2011 Pearson Education, Inc.
Module 10.4: Facial expression muscles
•
Muscles of facial expression
•
Originate on skull surface
•
Insert into superficial fascia and dermis of skin
•
Actions move skin
A&P Flix: Buccinator
Animation: Axial Muscles: Head and Neck
© 2011 Pearson Education, Inc.
Epicranial aponeurosis
Frontal belly of
occipitofrontalis
Orbicularis oculi
An anterior view showing
superficial muscles on
the right side of the face,
and deeper muscles on
the left side of the face.
Temporalis
Corrugator supercilii
Procerus
Nasalis
Zygomaticus minor
Zygomaticus major
Orbicularis oris
Levator labii superioris
Levator anguli oris
Masseter
Buccinator
Risorius
Depressor anguli oris
Platysma
Mentalis (cut)
Depressor labil inferioris
Thyroid
cartilage
of the larynx
Clavicle
Figure 10.4
© 2011 Pearson Education, Inc.
1
A lateral view showing the
major facial muscles
Occipital belly
of the occipitofrontalis muscle
Frontal belly of the
occipitofrontalis
muscle
Orbicularis oculi
Nasalis
Muscles of the Mouth and Cheek
Levator labii superioris
Zygomaticus minor
Zygomaticus major
Buccinator
Orbicularis oris
Risorius
Mentalis (cut)
Temporalis
Masseter
Depressor labil inferioris
Depressor anguli oris
Figure 10.4
© 2011 Pearson Education, Inc.
2
Module 10.4 Review
a. Identify the muscles associated with the mouth.
b. State whether the following muscles involve the
mouth, eye, nose, ear, scalp, or neck:
buccinator, corrugator supercilii, mentalis,
nasalis, platysma, procerus, and risorius.
c. Explain how an individual is able to consciously
move the skin on the scalp but is not able to
consciously move the skin of the thigh.
© 2011 Pearson Education, Inc.
Module 10.5: Muscles of external eye and
mastication
•
Extrinsic eye muscles position the eye
•
•
Six muscles insert on surface of eye and originate in
orbit
Muscles of mastication move the lower jaw
•
All mastication muscles are seen on the lateral sides
of the skull
© 2011 Pearson Education, Inc.
A lateral view of the right eye (left) showing five extrinsic eye muscles, and a
medial view of the right eye (right) showing the sixth extrinsic eye muscle
Superior rectus Superior oblique Frontal bone
Superior rectus
Superior oblique
Levator palpebrae
superioris
Optic nerve
Trochlea
(ligamentous sling)
Inferior oblique
Inferior rectus
Lateral rectus Maxilla
Medial rectus
Optic nerve
Figure 10.5
© 2011 Pearson Education, Inc.
1
– 2
Module 10.5: Muscles of external eye and
mastication
A&P Flix: Temporalis
A&P Flix: Masseter
© 2011 Pearson Education, Inc.
Two anterior views of the right eye: the directions of eye movements produced by each extrinsic
eye muscle operation independently (left), and the origins of the extrinsic eye muscles in the orbit (right)
Superior
rectus
Trochlea
Superior oblique
Levator
palpebrae
superioris
Superior
rectus
Oculomotor
nerve (III)
Lateral
rectus
Inferior
oblique
Medial rectus
Lateral rectus
Abducens
nerve (VI)
Inferior rectus
Inferior
oblique
Trochlear
nerve (IV)
Trochlea
Superior
oblique
Medial
rectus
Optic
nerve (II)
Inferior
rectus
Figure 10.5
© 2011 Pearson Education, Inc.
3
–
4
Figure 10.5
© 2011 Pearson Education, Inc.
5
A superficial lateral view showing
the largest muscles of mastication
of the right side of the head
Superior temporal line
Temporalis
Capsule of
temporomandibular
joint
Zygomatic
arch
Masseter
Figure 10.5
© 2011 Pearson Education, Inc.
6
A lateral view showing the pterygoid
muscles after removal of the superficial
muscles and the right mandibular ramus
Lateral pterygoid
Medial pterygoid
Cut edge of mandible
Figure 10.5
© 2011 Pearson Education, Inc.
7
Figure 10.5
© 2011 Pearson Education, Inc.
8
Module 10.5 Review
a. Name the extrinsic eye muscles.
b. Which muscles have their origin on the
lateral pterygoid plates and their insertion on
the medial surface of the mandibular ramus?
c. If you were contracting and relaxing your
masseter muscle, what would you probably
be doing?
© 2011 Pearson Education, Inc.
Module 10.6: Muscles of the tongue, pharynx,
and neck
•
Muscles of the tongue are closely associated with
pharynx and neck muscles
•
Actions of these muscles assist in speaking and
chewing
•
Many help support the hyoid bone
© 2011 Pearson Education, Inc.
A lateral view showing the tongue muscles as dissected
after removal of the left half of the mandible
Styloid process
Palatoglossus
Styloglossus
Genioglossus
Hyoglossus
Mandible
(cut)
Hyoid bone
Figure 10.6
© 2011 Pearson Education, Inc.
1
–
2
A lateral view showing the major groups
of the muscles of the pharynx
Palatal muscles
Laryngeal
elevators
Pharyngeal
constrictors
Esophagus
Figure 10.6
© 2011 Pearson Education, Inc.
3
–
4
The anterior muscles of the neck
Mandible
Mylohyoid (cut and reflected)
Muscles of the
Floor of the Mouth
Mylohyoid
Small Muscles
of the Hyoid Bone
Digastric
Stylohyoid
Geniohyoid
Hyoid bone
Thyrohyoid
Sternocleidomastoid (cut)
Thyroid cartilage of larynx
Muscles Originating
at the Sternum
Omohyoid:
Superior belly
Inferior belly
Sternothyroid
Sternohyoid
Sternocleidomastoid
(sternal head)
Clavicle
Cut heads of sternocleidomastoid
Sternum
Figure 10.6
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5
Figure 10.6
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6
A superior view of the isolated mandible
Genioglossus
(cut)
Mylohyoid
Geniohyoid
Mandible
Hyoid bone
Figure 10.6
© 2011 Pearson Education, Inc.
7
Module 10.6 Review
a. List the muscles of the tongue.
b. Which muscles associated with the hyoid
form the floor of the mouth?
c. Which muscles elevate the soft palate?
© 2011 Pearson Education, Inc.
Module 10.7: Muscles of the vertebral column
•
Muscles of the vertebral column
•
Arranged in several layers
•
Originate or insert on ribs and processes of
vertebrae
•
The mass of muscles extends from sacrum to skull
•
Each muscle group composed of numerous separate
muscles of various lengths
•
Example: erector spinae muscles divide into:
• Spinalis group
• Longissimus group
• Iliocostalis group
© 2011 Pearson Education, Inc.
Module 10.7: Muscles of the vertebral column
•
Contains many extensors but few flexors
•
Vertebral column does not need massive series of
flexors because:
1. Many large trunk muscles flex vertebral column
2. Most of body weight is anterior and gravity tends to
flex spine
© 2011 Pearson Education, Inc.
The muscles of the vertebral column
Spinal Extensors, Superficial Layer
Splenius capitus
Erector Spinae Muscles
Longissimus capitis
Spinalis cervicis
Spinal Extensors, Deep Layer
Longissimus cervicis
Semispinalis Group
Iliocostalis cervicis
Semispinalis capitis
Iliocostalis thoracis
Semispinalis cervicis
Longissimus thoracis
Semispinalis thoracis
Spinalis thoracis
Multifidus
Iliocostalis lumborum
Spinal Flexors
Quadratus lumborum
Longus
capitus
The erector spinae
muscles, consisting of
the spinalis, longissimus,
and iliocostalis muscle
groups
Longus
colli
Thoracodorsal fascia
Muscles of the anterior
cervical spine
Posterior
view
© 2011 Pearson Education, Inc.
Figure 10.7
1
Module 10.7: Muscles of the vertebral column
A&P Flix: Splenius Capitis
A&P Flix: Semispinalis Capitis
A&P Flix: Iliocostalis
A&P Flix: Longissimus
A&P Flix: Spinalis
© 2011 Pearson Education, Inc.
Module 10.7 Review
a. List the spinal flexor muscles.
b. Which muscles enable you to extend the
neck?
© 2011 Pearson Education, Inc.
Module 10.8: Muscles of the trunk wall
•
Muscles of the trunk wall
• Oblique and rectus muscles form the muscular
walls of the trunk
• Actions of many trunk wall muscles assist in
breathing
• Many are layered with fibers running perpendicular
to other muscles producing antagonist actions
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The scalene muscles
Scalenes
Anterior view
Figure 10.8
© 2011 Pearson Education, Inc.
1
Module 10.8: Muscles of the trunk wall
Animation: Muscles of the Trunk
Animation: Axial Muscles: Rectus Muscle
A&P Flix: External Intercostals
A&P Flix: Internal Intercostals
A&P Flix: External Obliques
© 2011 Pearson Education, Inc.
Module 10.8: Muscles of the trunk wall
A&P Flix: Internal Obliques
A&P Flix: Rectus Abdominis
A&P Flix: Transversus Abdominis
© 2011 Pearson Education, Inc.
Serratus
anterior
External
oblique
Tendinous
inscription
Internal intercostal
External intercostal
External oblique (cut)
Internal oblique
Cut edge of
rectus sheath
Linea alba
Rectus abdominis
The muscles of the trunk: the superficial muscles on the
right side of the body, and deeper muscles of the oblique
and rectus groups on the left side of the body
© 2011 Pearson Education, Inc.
Figure 10.8
2
The muscles of the trunk: In the anterior view, the superficial muscles are
shown on the right side of the body, and deeper muscles of the oblique
and rectus groups are shown on the left side
Rectus
Xiphoid Costal
External
abdominis process cartilages oblique
Inferior
vena cava
External
intercostal
Internal
intercostal
Central tendon
of diaphragm
Esophagus
Serratus
anterior
Diaphragm
Thoracic aorta
Spinal cord Erector spinae group
Superior view through the thoracic cavity looking
down at the diaphragm
© 2011 Pearson Education, Inc.
Figure 10.8
3
The muscles of the trunk: In the anterior view, the superficial
muscles are shown on the right side of the body, and deeper
muscles of the oblique and rectus groups are shown on the
left side
Rectus abdominis
Rectus sheath
Linea alba
External
oblique
Transversus
abdominis
Internal
oblique
Thoracolumbar
fascia
© 2011 Pearson Education, Inc.
L3
Quadratus
lumborum
Horizontal section through
the abdominal cavity
Figure 10.8
4
An inferior view of the diaphragm
Sternum
Xiphoid process
Central tendon
of diaphragm
Costal cartilages
Inferior
vena cava
Esophagus in esophageal hiatus
Impression
for liver
Impression
for stomach
Aorta
12th rib
L2
L3
L4
Quadratus
lumborum (cut)
Figure 10.8
© 2011 Pearson Education, Inc.
6
Figure 10.8
© 2011 Pearson Education, Inc.
7
Module 10.8 Review
a. Which muscle connects the ribs and sternum
to the pubic bones?
b. Which muscle forms the deepest layer of the
abdominal wall muscles?
c. What is the action of the external oblique
muscle?
© 2011 Pearson Education, Inc.
Module 10.9: Muscles of the pelvic floor
•
Muscles of the pelvic floor
•
Form the perineum (muscular sheet that spans pelvic
outlet)
•
Females and males have different superficial muscles
•
•
No differences in deep perineal musculature
Urogenital and pelvic diaphragms do not completely close
outlet
•
Urethra, vagina, and anus all pass through
• Muscular sphincters surround openings and control urination and
defecation
•
Muscles, nerves, and blood vessels also pass
© 2011 Pearson Education, Inc.
The muscles of the pelvic floor
Deep Dissections
Superficial Dissections
Urethra
Urogenital Diaphragm
External urethral sphincter
Deep transverse perineal
Ischiocavernosus
Bulbospongiosus
Central tendon of perineum
Vagina
Superficial
transverse perineal
Pelvic Diaphragm
Pubococcygeus
Iliococcygeus
Anus
Levator
ani
External anal sphincter
Coccygeus
Gluteus maximus
Sacrotuberous ligament
Female
The muscles of the pelvic floor in females
Figure 10.9
© 2011 Pearson Education, Inc.
1
The muscles of the pelvic floor
Superficial Dissections
Urethra (connecting
segment removed)
Testis
UROGENITAL
TRIANGLE OF
PERINEUM
Ischiocavernosus
Bulbospongiosus
Urogenital Diaphragm
External urethral sphincter
Deep transverse perineal
Central tendon of perineum
Superficial
transverse perineal
Pelvic Diaphragm
Anus
Pubococcygeus
Levator
Iliococcygeus
ani
External anal sphincter
Gluteus maximus
Coccygeus
Sacrotuberous ligament
The muscles of the pelvic floor in males
Male
ANAL
TRIANGLE
Figure 10.9
© 2011 Pearson Education, Inc.
2
Module 10.9 Review
a. Which muscles make up the urogenital
diaphragm?
b. In females, what is the action of the
bulbospongiosus muscle?
c. The coccygeus muscle extends from the
sacrum and coccyx to which structure?
© 2011 Pearson Education, Inc.
Section 3: Appendicular Muscles
• Learning Outcomes
• 10.10 Identify the principal appendicular
muscles.
• 10.11 Identify the principal muscles of the
pectoral girdle, along with their origins,
insertions, and actions.
• 10.12 Identify the principal muscles that move
the arm, along with their origins,
insertions, and actions.
© 2011 Pearson Education, Inc.
Section 3: Appendicular Muscles
• Learning Outcomes
• 10.13 Identify the principal muscles that move
the forearm and hand, along with their
origins, insertions, and actions.
• 10.14 Identify the principal muscles that move
the hand and fingers, along with their
origins, insertions, and actions.
• 10.15 Identify the principal intrinsic hand
muscles, along with their origins,
insertions, and actions.
© 2011 Pearson Education, Inc.
Section 3: Appendicular Muscles
• Learning Outcomes
• 10.16 Identify the principal muscles that move
the thigh, along with their origins,
insertions, and actions.
• 10.17 Identify the principal muscles that move
the leg, along with their origins, insertions,
and actions.
• 10.18 Identify the principal muscles that move
the foot and toes, along with their origins,
insertions, and actions.
© 2011 Pearson Education, Inc.
Section 3: Appendicular Muscles
• Learning Outcomes
• 10.19 Identify the principal intrinsic foot muscles,
along with their origins, insertions, and
actions.
• 10.20 Describe the deep fascia and its
relationship to the various limb muscle
compartments.
© 2011 Pearson Education, Inc.
Section 3: Appendicular Muscles
•
Appendicular Muscles
•
Upper limb
•
Muscles That Position the Pectoral Girdle
• Originate on axial skeleton and insert on clavicle and scapula
•
Muscles That Move the Arm
• Originate on pectoral girdle and thoracic cage and insert on
humerus
•
Muscles That Move the Forearm and Hand
• Primarily originate on pectoral girdle and arm, and insert on
radius, ulna, and carpals
© 2011 Pearson Education, Inc.
Section 3: Appendicular Muscles
•
Upper limb (continued)
•
Extrinsic Muscles of the Hand and Fingers
•
•
Primarily originate on humerus and insert on
metacarpals and phalanges
Intrinsic Muscles of the Hand
•
Perform fine movements
•
Primarily originate on carpals and metacarpals
and insert on phalanges
© 2011 Pearson Education, Inc.
Section 3: Appendicular Muscles
•
Lower Limb
•
Muscles That Move the Thigh
•
•
Originate in pelvic region and typically insert on femur
Muscles That Move the Leg
•
•
Originate on pelvis and femur and insert on tibia and/or
fibula
Extrinsic Muscles that Move the Foot and Toes
•
•
Originate on tibia and fibula and insert on tarsals,
metatarsals, and/or phalanges
Intrinsic Muscles of the Foot
•
Primarily originate on tarsals and metatarsals and insert
on phalanges
© 2011 Pearson Education, Inc.
Module 10.10: Large muscles originating on the
trunk
•
Large muscles originating on the trunk
•
In general, control gross movements of limbs
•
Are often large and powerful
•
Distally, limb muscles get smaller and more
numerous
• Actions become more precise
•
Appendicular muscles on posterior of trunk often
originate on large girdle bones and proximal limb
bones
© 2011 Pearson Education, Inc.
Module 10.10 Review
a. Which axial muscle is often known as the “sixpack” in fit individuals?
b. Describe the appearance of the appendicular
muscles as you move proximally to distally.
c. Identify to which division, axial or appendicular,
the following muscles belong: deltoid, external
oblique, gluteus maximus, pectoralis major,
platysma, and rectus femoris.
© 2011 Pearson Education, Inc.
Module 10.11: Muscles that position pectoral
girdle
•
Muscles that position the pectoral girdle
• Also serve to anchor pectoral girdle to axial
skeleton
• Smaller range of motion than other appendicular
muscles
• Help increase upper limb mobility
• Trapezius is largest muscle of group
© 2011 Pearson Education, Inc.
An anterior view of the muscles that position the pectoral girdle
Muscles That Position
the Pectoral Girdle
Trapezius
Levator scapulae
Muscles That Position
the Pectoral Girdle
Subclavius
Pectoralis minor
Pectoralis minor
(cut)
Serratus anterior
Internal intercostals
External intercostals
T12
Figure 10.11
© 2011 Pearson Education, Inc.
1
A posterior view of the muscles that position the pectoral girdle
Superficial Dissection
Deep Dissection
Muscles That
Position the
Pectoral Girdle
Muscles That
Position the
Pectoral Girdle
Levator scapulae
Trapezius
Rhomboid minor
Rhomboid major
Scapula
Serratus anterior
T12 vertebra
Figure 10.11
© 2011 Pearson Education, Inc.
2
Figure 10.11
© 2011 Pearson Education, Inc.
3
Module 10.11: Muscles that position pectoral
girdle
A&P Flix: Trapezius
A&P Flix: Levator Scapula
A&P Flix: Serratus Anterior
A&P Flix: Rhomboid Minor
A&P Flix: Rhomboid Major
© 2011 Pearson Education, Inc.
Module 10.11: Muscles that position pectoral
girdle
A&P Flix: Muscles that Act on the Shoulder Joint
and Humerus: An Overview
Animation: Muscles of the Pectoral Girdle
A&P Flix: Movement of the Pectoral Girdle
© 2011 Pearson Education, Inc.
Module 10.11 Review
a. Identify the largest of the superficial muscles
that position the pectoral girdle.
b. Which muscles enable you to shrug your
shoulders?
c. Which muscle originates on the first rib and
inserts on the inferior border of the clavicle?
© 2011 Pearson Education, Inc.
Module 10.12: Muscles that move the arm
•
Action of muscles positioning the arm are best understood
by considering pull or line of force (action line) relative to
glenoid cavity
•
Rotator cuff
•
Muscles often injured in sports involving ball throwing
•
Consists of four muscles (SITS)
1.
Supraspinatus
2.
Infraspinatus
3.
Teres minor
4.
Subscapularis
Animation: Appendicular Muscles: Arm
© 2011 Pearson Education, Inc.
Deep Dissection
Superficial Dissection
Sternum
Clavicle
Muscles That
Move the Arm
Deltoid
Pectoralis major
Ribs (cut)
Muscles That
Move the Arm
Subscapularis
Coracobrachialis
Teres major
An anterior view of the
muscles that move the
arm
Vertebra T12
Figure 10.12
© 2011 Pearson Education, Inc.
1
Module 10.12: Muscles that move the arm
A&P Flix: Rotator Cuff Muscles: An Overview
A&P Flix: Rotator Cuff Muscles
A&P Flix: Movement from the Rotator Cuff Muscles
A&P Flix: Muscles that Cross Glenohumeral Joint
© 2011 Pearson Education, Inc.
Module 10.12: Muscles that move the arm
A&P Flix: Latissimus Dorsi
A&P Flix: Supraspinatus
A&P Flix: Infraspinatus
A&P Flix: Teres Major
A&P Flix: Teres Minor
© 2011 Pearson Education, Inc.
Module 10.12: Muscles that move the arm
A&P Flix: Subscapularis
A&P Flix: Pectoralis Major
A&P Flix: Pectoralis Minor
A&P Flix: Deltoid
© 2011 Pearson Education, Inc.
Module 10.12: Muscles that move the arm
A&P Flix: Scapular Muscles of the
Glenohumeral Joint
A&P Flix: Axial Muscles of the
Glenohumeral Joint
A&P Flix: Movement at the Glenohumeral
Joint: An Overview
A&P Flix: Movement at the Glenohumeral
Joint
© 2011 Pearson Education, Inc.
Superficial Dissection
Muscles That
Move the Arm
Vertebra T1
Supraspinatus
Deltoid
Latissimus dorsi
Deep Dissection
Muscles That
Move the Arm
Supraspinatus
Infraspinatus
Teres minor
Teres major
Thoracolumbar fascia
A posterior view of the
muscles that move the
arm
Figure 10.12
© 2011 Pearson Education, Inc.
2
The actions of muscles that position the arm
Abduction
Extension
Flexion
Deltoid
POSTERIOR
GLENOID
CAVITY
Tendons of
biceps brachii
ANTERIOR
Teres minor
Subscapularis
Triceps
brachii
Lateral rotation
Teres
major
Adduction
© 2011 Pearson Education, Inc.
Medial rotation
Figure 10.12
4
Figure 10.12
© 2011 Pearson Education, Inc.
3
Module 10.12 Review
a. Define action line.
b. Name the muscle that abducts the upper arm.
c. Which muscle originates on the anterior
surface of the scapula and inserts on the
lesser tubercle of the humerus?
© 2011 Pearson Education, Inc.
Module 10.13: Muscles that move the forearm
and hand
•
Muscles that move the forearm and hand
•
Special connective tissues
•
Extensor retinaculum
• Wide band of connective tissue holding extensor muscles in place
•
Flexor retinaculum
• Wide band of connective tissue holding flexor muscles in place
• Carpal tunnel syndrome (inflammation of medial nerve passing
through)
•
Synovial tendon sheaths
• Tubular bursae surrounding tendons where they cross bones
Animation: Appendicular Muscles: Forearm and Hand
© 2011 Pearson Education, Inc.
A posterior view showing the superficial layer
of muscles involved in extension at the elbow
and wrist
Elbow Extensors
Triceps brachii
Anconeus
Wrist Extensors
Extensor carpi ulnaris
Olecranon
of ulna
Flexor carpi
ulnaris
Extensor carpi radialis
longus
Extensor carpi radialis
brevis
Radius
Ulna
Extensor
retinaculum
Figure 10.13
© 2011 Pearson Education, Inc.
1
Module 10.13: Muscles that move the forearm
and hand
A&P Flix: The Elbow Joint and Forearm: An Overview
A&P Flix: Muscles of the Elbow Joint
A&P Flix: Movement at the Elbow Joint
A&P Flix: Muscles of the Forearm
© 2011 Pearson Education, Inc.
Module 10.13: Muscles that move the forearm
and hand
A&P Flix: Biceps Brachii
A&P Flix: Brachialis
A&P Flix: Triceps Brachii
A&P Flix: Pronator Teres
A&P Flix: Brachioradialis
© 2011 Pearson Education, Inc.
Module 10.13: Muscles that move the forearm
and hand
A&P Flix: Supinator
A&P Flix: Flexor Digitorum Superficialis
A&P Flix: Flexor Carpi Radialis
A&P Flix: Flexor Carpi Ulnaris
© 2011 Pearson Education, Inc.
Module 10.13: Muscles that move the forearm
and hand
A&P Flix: Extensor Digitorum
A&P Flix: Extensor Carpi Radialis Longus
A&P Flix: Extensor Carpi Radialis Brevis
A&P Flix: Extensor Carpi Ulnaris
© 2011 Pearson Education, Inc.
An anterior view showing the superficial muscles
involved in flexion at the elbow and wrist
Coracoid process
of scapula
Humerus
Elbow Flexors
Biceps brachii
Elbow Extensors
Triceps brachii
Brachialis
Brachioradialis
Medial epicondyle
of humerus
Wrist Flexors
Flexor carpi radialis
Palmaris longus
Flexor carpi ulnaris
Pronators and
Supinators
Pronator teres
Supinator
Pronator
quadratus
Flexor retinaculum
Figure 10.13
© 2011 Pearson Education, Inc.
2
A cross section of the right wrist (palm up) showing the synovial
tendon sheaths and nearby structure
Median nerve
Flexor retinaculum
Synovial tendon sheaths
Carpal tunnel
Pisiform
Triquetrum
Lunate
Carpal
bones
Scaphold
Figure 10.13
© 2011 Pearson Education, Inc.
4
Module 10.13 Review
a. Define retinaculum.
b. On which surface, anterior or posterior, are
the wrist extensors located?
c. Which muscles are involved in turning a
doorknob?
© 2011 Pearson Education, Inc.
Module 10.14: Muscles that move the hand and
fingers
•
Muscles that move the hand and fingers
•
Extensors usually lie along the posterior and lateral
surfaces of the forearm
• Muscles that extend fingers can only be seen after
removal of those that extend the wrist
•
Flexors usually lie along the anterior and medial
surfaces
© 2011 Pearson Education, Inc.
Two anterior views of the muscles that move the hand and fingers
Median nerve
Tendon of
biceps brachii
Brachial artery
Radius
Flexor carpi ulnaris
(retracted)
Brachioradialis
(retracted)
Supinator
Cut tendons of
flexor digitorum
superficialis
Muscles That Flex the
Fingers and Thumb
Flexor digitorum superficialis
Flexor digitorum profundus
Flexor pollicis longus
LATERAL
MEDIAL
Anterior View,
Middle Layer
Anterior View,
Deepest Layer
Figure 10.14
© 2011 Pearson Education, Inc.
1
–
2
Module 10.14: Muscles that move the hand and
fingers
A&P Flix: Muscles that Act on the Wrist and Fingers:
An Overview
A&P Flix: Anterior Muscles of the Wrist and Fingers
A&P Flix: Posterior Muscles of the Wrist and Fingers
A&P Flix: Carpal Tunnel
A&P Flix: Movements of the Wrist and Fingers
© 2011 Pearson Education, Inc.
Two posterior views of the muscles that move the hand and fingers
Anconeus
Anconeus
Muscles That
Extend the Fingers
Supinator
Extensor digitorum
Muscles That Move
the Thumb
Extensor digiti minimi
Abductor pollicis longus
Extensor pollicis longus
Abductor pollicis longus
Extensor pollicis brevis
Tendon of extensor
pollicis longus
Extensor
indicis
Ulna
Tendon of extensor
digiti minimi (cut)
MEDIAL
Posterior View,
Middle Layer
LATERAL
Extensor pollicis brevis
Radius
Tendon of extensor
digitorum (cut)
Posterior View,
Deepest Layer
Figure 10.14
© 2011 Pearson Education, Inc.
3
–
4
Module 10.14 Review
a. List the muscles that extend the fingers.
b. Name the muscles that abduct the wrist.
c. The names of muscles associated with the
thumb frequently include what term?
© 2011 Pearson Education, Inc.
Module 10.15: Intrinsic muscles of the hand
•
Intrinsic muscles of the hand
•
Provide fine movement of hand
•
•
No muscles originate on phalanges
•
•
More powerful movements are controlled by forearm
muscles
Tendons extend across distal finger joints
Responsible for:
1. Flexion/extension of fingers at metacarpophalangeal joints
2. Abduction/adduction of fingers at metacarpophalangeal
joints
3. Opposition/reposition of thumb
© 2011 Pearson Education, Inc.
The intrinsic muscles of the hand
Intrinsic Muscles
of the Hand
Tendons of flexor digitorum
Lumbricals
Palmar interosseus
First dorsal interosseus
Abductor digiti minimi
Flexor digiti minimi brevis
Opponens digiti minimi
Palmaris brevis (cut)
Intrinsic Muscles
of the Thumb
Adductor pollicis
Flexor pollicis brevis
Opponens pollicis
Abductor pollicis brevis
Anterior view
Figure 10.15
© 2011 Pearson Education, Inc.
1
The intrinsic muscles of the hand
Tendons
of extensor
digitorum
Intrinsic Muscles of the Hand
First dorsal interosseus muscle
Abductor digiti minimi
Extensor retinaculum
Posterior view
Figure 10.15
© 2011 Pearson Education, Inc.
2
Module 10.15 Review
a. Name the intrinsic muscles of the thumb.
b. Which muscles originate on the phalanges?
c. If there are no muscles in the fingers, how are
we able to move them?
© 2011 Pearson Education, Inc.
Module 10.16: Muscles that move the thigh
•
Muscles that move the thigh
•
Understanding diverse actions of thigh/hip muscles
from orientation to hip joint
•
Muscles originating on surface of pelvis and inserting
on femur
• Produce characteristic movements by position relative to
acetabulum
•
Many muscles are broad and have more than one
action line (more than one action at hip)
•
Example: Adductor magnus
• Produces flexion, extension, and adduction at hip
© 2011 Pearson Education, Inc.
The muscles that move the thigh
Iliac crest
Sacrum
Gluteal Group
Gluteus medius
(cut)
Gluteus medius
Gluteus maximus
(cut)
Gluteus maximus
Gluteus minimus
Tensor fasciae latae
Iliotibial tract
Gluteal muscles, posterior view
Lateral view of the gluteal region
Figure 10.16
© 2011 Pearson Education, Inc.
1
–
2
Module 10.16: Muscles that move the thigh
A&P Flix: Muscles that Act on the Hip Joint and Femur:
An Overview
A&P Flix: Anterior Muscles that Cross the Hip Joint
A&P Flix: Medial Muscles that Cross the Hip Joint
A&P Flix: Posterior Muscles that Cross the Hip Joint
A&P Flix: Movement at the Hip Joint: An Overview
A&P Flix: Movement at the Hip Joint
© 2011 Pearson Education, Inc.
Module 10.16: Muscles that move the thigh
A&P Flix: Sartorius
A&P Flix: Tensor Fasciae Latae
A&P Flix: Iliiopsoas
A&P Flix: Pectineus
© 2011 Pearson Education, Inc.
Module 10.16: Muscles that move the thigh
A&P Flix: Rectus Femoris
A&P Flix: Vastus Medialis
A&P Flix: Vastus Intermedius
A&P Flix: Vastus Lateralis
© 2011 Pearson Education, Inc.
Module 10.16: Muscles that move the thigh
A&P Flix: Gluteus Maximus
A&P Flix: Gluteus Medius
A&P Flix: Semimembranosus
A&P Flix: Semitendinosus
A&P Flix: Biceps Femoris
© 2011 Pearson Education, Inc.
The muscles that move the thigh
Iliopsoas Group
Gluteal Group
Gluteus
maximus
(cut)
Gluteus Gluteus
medius minimus
(cut)
Tensor
fasciae
latae
An anterior view showing the
isolated iliopsoas muscle
group and the adductor group
Psoas major
Iliacus
L5
Lateral Rotator
Group
Inguinal ligament
Piriformis
Superior gemellus
Adductor Group
Obturator internus
Pectineus
Obturator externus
Adductor brevis
Inferior gemellus
Adductor longus
Quadratus femoris
Adductor magnus
Gracilis
Ischial tuberosity
Iliotibial tract
A lateral view of a dissection of the gluteal region
Figure 10.16
© 2011 Pearson Education, Inc.
3
–
4
Module 10.16 Review
a. Name the muscles that compose the gluteal
group.
b. Identify the muscle whose origin is the lateral
border of the ischial tuberosity and whose
insertion is the intertrochanteric crest of the
femur.
c. Which leg movement would be impaired by
injury to the obturator muscles?
© 2011 Pearson Education, Inc.
Module 10.17: Muscles that move the leg
•
Muscles that move the leg
•
Flexors of the knee
• Originate on pelvic girdle and extend along posterior and medial
surfaces of thigh
•
Extensors of the knee
• Originate on femoral surface and extend along anterior and lateral
surfaces of thigh
• Collectively called quadriceps muscles or quadriceps femoris
Animation: Appendicular Muscles: Lower Limb
Animation: Appendicular Muscles: Thigh
© 2011 Pearson Education, Inc.
The muscles that move the leg
Iliac crest
Anterior superior
iliac spine
Inguinal ligament
Gluteus medius
Tensor fasciae
latae
Iliacus
Psoas major
Iliopsoas
Pubic tubercle
Gluteus maximus
Tensor fasciae
latae
Pectineus
Adductor longus
Gracilis
Adductor magnus
Gracilis
Iliotibial tract
Flexors of the Knee
Biceps femoris
Semitendinosus
Sartorius
Extensors of the Knee
(Quadriceps muscles)
Rectus femoris
Vastus intermedius
(lies deep to the
rectus femoris and
vastus lateralis)
Vastus lateralis
Vastus medialis
Quadriceps tendon
Semimembranosus
Sartorius
Patella
Popliteus
Patellar ligament
The flexors of the knee
© 2011 Pearson Education, Inc.
The extensors of the knee, collectively called
the quadriceps muscles or the quadriceps femoris
Figure 10.17
1
–
2
Module 10.17: Muscles that move the leg
A&P Flix: Muscles that Cross the Knee Joint: An
Overview
A&P Flix: Anterior Extensors that Act on the Knee
A&P Flix: Posterior Flexors that Act on the Knee
A&P Flix: Movement at the Knee Joint
© 2011 Pearson Education, Inc.
Module 10.17: Muscles that move the leg
A&P Flix: Tibialis Anterior
A&P Flix: Extensor Digitorum Longus
A&P Flix: Extensor Hallucis Longus
A&P Flix: Fibularis Longus
A&P Flix: Gastrocnemius
© 2011 Pearson Education, Inc.
Module 10.17: Muscles that move the leg
A&P Flix: Soleus
A&P Flix: Tibialis Posterior
A&P Flix: Flexor Digitorum Longus
A&P Flix: Flexor Hallucis Longus
© 2011 Pearson Education, Inc.
A cross sectional view showing
the positions of the major thigh
muscles relative to the femur
POSTERIOR
Semitendinosus
Semimembranosus
Sciatic nerve
Adductor magnus
Biceps femoris
Gracilis
Adductor longus
Vastus lateralis
Great saphenous vein
Vastus intermedius
Sartorius
Femur
Vastus medialis
Rectus femoris
ANTERIOR
Figure 10.17
© 2011 Pearson Education, Inc.
4
Module 10.17 Review
a. Name the quadriceps muscles.
b. Which muscles flex the knee?
c. Identify the muscle whose origin is on the
lateral condyle of the femur.
© 2011 Pearson Education, Inc.
Module 10.18: Extrinsic muscles that move the
foot and toes
•
Extrinsic muscles that move the foot and toes
•
Gastrocnemius and Soleus
• Largest muscles associated with ankle
movement
• Produce ankle extension (plantar flexion)
•
Muscles that move toes are much smaller and
originate on tibia and/or fibula
• Tendons stabilized by superior and inferior
retinacula
Animation: Appendicular Muscles: Leg and Foot
© 2011 Pearson Education, Inc.
The multiple muscle layers in the posterior leg
Deep Dissection
Superficial Dissection
Ankle Extensors
Plantaris
Head of fibula
Gastrocnemius
Popliteus
Soleus
Ankle Extensors
(Deep)
Tibialis posterior
Fibularis longus
Fibularis brevis
Digital Flexors
Gastrocnemius
(cut and removed)
Flexor digitorum
longus
Flexor hallucis
longus
Calcaneal
tendon
Calcaneus
Tendon of flexor digitorum
longus
Tendon of fibularis brevis
Tendon of fibularis
longus
Figure 10.18
© 2011 Pearson Education, Inc.
1
Module 10.18: Extrinsic muscles that move the
foot and toes
A&P Flix: Muscles that the Act on Ankle and Foot:
An Overview
A&P Flix: Anterior Muscles that Act on the Ankle and
Foot
A&P Flix: Lateral Muscles that Act on the Ankle
and Foot
A&P Flix: Posterior Muscles that Act on the Ankle
and Foot
A&P Flix: Movements of the Ankle and Foot
© 2011 Pearson Education, Inc.
The arrangement of the major
superficial muscles that move
the foot and toes
Lateral View
Medial View
Patella
Iliotibial tract
Head of fibula
Ankle Extensors
Gastrocnemius
Fibularis longus
Patellar
ligament
Ankle Flexors
Tibialis anterior
Soleus
Digital Extensors
Calcaneal tendon
Inferior extensor
retinaculum
Ankle Extensors
Gastrocnemius
Soleus
Fibularis brevis
Superior extensor
retinaculum
Medial surface
of tibial shaft
Extensor digitorum
longus
Tendon of extensor
hallucis longus
Tendon of
tibialis anterior
Tibialis posterior
Superior extensor
retinaculum
Calcaneal tendon
Inferior extensor
retinaculum
Figure 10.18
© 2011 Pearson Education, Inc.
2
–
3
Module 10.18 Review
a. Name the muscles involved in flexing the
toes.
b. Name the muscles involved in extending the
ankle.
c. How would a torn calcaneal tendon affect
movement of the foot?
© 2011 Pearson Education, Inc.
Module 10.19: Intrinsic muscles of the foot
•
Intrinsic muscles of the foot
•
Retinacula stabilize tendons descending from
leg
•
More numerous on inferior surface of foot
•
Many are flexors that tense during ankle
extension and help “push off” when walking
• Provide padding
• Assist in maintaining arches of foot
© 2011 Pearson Education, Inc.
A superior view of the foot
showing the intrinsic muscles
of the foot and toes
Superior extensor
retinaculum
Medial malleolus
of tibia
Lateral malleolus
of fibula
Inferior extensor
retinaculum
Tendons of extensor
digitorum longus
Intrinsic Muscles
of the Foot, Toes 2–5
Tendon of
tibialis anterior
Intrinsic Muscles
of the Foot, Great Toe
Extensor hallucis
brevis
Abductor hallucis
Dorsal interossei
Tendons of extensor
digitorum brevis
Tendon of extensor
hallucis longus
Figure 10.19
© 2011 Pearson Education, Inc.
1
The intrinsic muscles on the inferior surface of the foot
Superficial Muscles of
the Sole of the Foot
Fibrous
tendon
sheaths
Tendons of flexor
digitorum brevis
Instrinsic Muscles
of the Foot
Deep Muscles
of the Sole
of the Foot
Tendon of flexor
hallucis longus
Lumbricals
Flexor hallucis brevis
Flexor digiti minimi brevis
Adductor hallucis
Quadratus plantae
Flexor digitorum brevis
Abductor digiti minimi
Plantar aponeurosis (cut)
Tendon of
flexor digitorum
longus
Tendon of tibialis
posterior
Tendon of
fibularis longus
Calcaneus
Figure 10.19
© 2011 Pearson Education, Inc.
2
A cross section showing the intrinsic muscles of the foot
Instrinsic Muscles
of the Foot
Metatarsal bones
Tendons of extensor
digitorum longus
Instrinsic Muscles
of the Foot
Tendons of extensor
digitorum brevis
Tendon of extensor
hallucis brevis
Flexor digiti minimi
brevis
Dorsal interossei
Adductor hallucis
Abductor digiti minimi
Adductor hallucis
Plantar interossei
Flexor hallucis brevis
Tendons of flexor
digitorum brevis
Lumbricals
Tendons of flexor
digitorum longus
Plantar
aponeurosis
Figure 10.19
© 2011 Pearson Education, Inc.
4
Module 10.19 Review
a. Identify the intrinsic muscle that flexes the
great toe.
b. What are the functions of the superior and
inferior retinacula of the foot?
c. Describe the origin, insertion, and action of
the lumbrical muscles.
© 2011 Pearson Education, Inc.
Module 10.20: Deep fascia
• Deep fascia organizes limb muscles into
compartments
• Muscles within a compartment have compatible
functions
• Each compartment has characteristic blood supply and
innervation
• Clinically important because trauma can cause bleeding
within compartment
• Elevates pressure and compresses blood vessels and
nerves
• = Compartment syndrome
• Can lead to paralysis or death of muscles if not relieved in 2–
4 hours
© 2011 Pearson Education, Inc.
Module 10.20 Review
a. Name the six possible compartments of the
muscles of the limbs.
b. Define compartment syndrome.
c. Propose a reason why compartment
syndrome can be life threatening.
© 2011 Pearson Education, Inc.