Download Chapter 11 - Las Positas College

PowerPoint® Lecture Slides
prepared by Leslie Hendon,
University of Alabama,
Birmingham
11
HUMAN
ANATOMY
PART 1
Muscles of
the Body
fifth edition
MARIEB | MALLATT | WILHELM
Copyright © 2008 Pearson Education, Inc.,
publishing as Benjamin Cummings
Muscles of the Body

Skeletal muscles
 Produce movements
 Blinking of eye, standing on tiptoe, swallowing
food, etc.



General principles of leverage
Muscles act with or against each other
Criteria used in naming muscles
Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings
Lever Systems: Bone-Muscle Relationships

Movement of skeletal muscles involves leverage
 Lever – a rigid bar that moves
 Fulcrum – a fixed point
 Effort – applied force
 Load – resistance
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Lever Systems
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Figure 11.1a
Lever Systems
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Figure 11.1b
Lever Systems: Bone-Muscle Relationships



Bones – act as levers
Joints – act as fulcrums
Muscle contraction – provides effort
 Applies force where muscle attaches to bone

Load – bone, overlying tissue, and anything lifted
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Lever Systems: Bone-Muscle Relationships

Levers allow a given effort to
 Move a heavier load
 Move a load farther

Mechanical advantage
 Moves a large load over small distances

Mechanical disadvantage
 Allows a load to be moved over a large distance
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Lever Systems: Bone-Muscle Relationships

First-class lever
 Effort applied at one end
 Load is at the opposite end
 Fulcrum is located between load and effort
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Lever Systems: Bone-Muscle Relationships
 Examples – seesaws, scissors, and lifting your head
off your chest
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Figure 11.2a
Lever Systems: Bone-Muscle Relationships

Second-class lever
 Effort applied at one end
 Fulcrum is at the opposite end
 Load is between the effort and fulcrum
 Examples – wheelbarrow or standing on tiptoe
 An uncommon type of lever in the body
 Work at a mechanical advantage
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Lever Systems: Bone-Muscle Relationships
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Figure 11.2b
Lever Systems: Bone-Muscle Relationships

Third-class lever
 Effort is applied between the load and the fulcrum
 Work speedily
 Always at a mechanical disadvantage
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Figure 11.2c
Lever Systems: Bone-Muscle Relationships

Most skeletal muscles are third-class levers
 Example – biceps brachii
 Fulcrum – the elbow joint
 Force – exerted on the proximal region of the radius
 Load – the distal part of the forearm
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Arrangement of Fascicles in Muscles

Skeletal muscles – consist of fascicles
 Fascicles – arranged in different patterns
 Fascicle arrangement – tells about action of a
muscle
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Arrangement of Fascicles in Muscles

Types of fascicle arrangement
 Parallel – fascicles run parallel to the long axis of
the muscle
 Strap-like – sternocleidomastoid
 Fusiform – biceps brachii
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Arrangement of Fascicles in Muscles

Types of fascicle arrangement
 Convergent
 Origin of the muscle is broad
 Fascicles converge toward the tendon of insertion
 Example – pectoralis major
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Arrangement of Fascicles in Muscles

Types of fascicle arrangement
 Pennate
 Unipennate – fascicles insert into one side of the
tendon
 Bipennate – fascicles insert into the tendon from
both sides
 Multipennate – fascicles insert into one large
tendon from all sides
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Arrangement of Fascicles in Muscles

Circular
 Fascicles are arranged in concentric rings
 Surround external body openings
 Sphincter – general name for a circular muscle
 Examples
 Orbicularis oris and orbicularis oculi
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Arrangement of Fascicles in Muscles
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Figure 11.3
Organization Scheme Based on Embryonic Development

Overview based upon
 Embryonic origin
 General function

Muscles develop from mesoderm
 Myotomes
 Somitomeres
 The first seven myotomes of the head
 Splanchnic mesoderm
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Development and Basic Organization of the Muscles
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Figure 11.4a, b
Organization Scheme Based on Embryonic Development

Muscles organized into four groups
 Musculature of the visceral organs
 Pharyngeal arch muscles
 Axial muscles
 Limb muscles
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Organization Scheme Based on Embryonic Development

Musculature of the visceral organs
 Includes – smooth and cardiac muscle
 Develops from splanchnic mesoderm

Pharyngeal arch muscles
 Includes
 Skeletal muscles of the pharynx
 Muscles of the head and neck
 Develop from the fourth to seventh somitomeres
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Pharyngeal Arch Muscles
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Figure 11.4c
Axial Muscles


Lie anterior and posterior to the body axis
Muscles of the
 Thorax, abdomen, and pelvis

Many muscles of the
 Neck and some of the head

Function to move the trunk and maintain posture
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Axial Muscles

Develop from myotomes and some somitomeres
 Dorsal regions of myotomes – deep muscles of the
back
 Ventral regions of myotomes – muscles of the trunk
and neck
 Respiratory muscles
 Anterior abdominal wall muscles
 Muscles of the pelvic floor
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Axial Muscles
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Figure 11.4d
Limb Muscles


Limb muscles arise from lateral parts of nearby
myotomes
Extensors
 Muscle mass dorsal to limb bones

Flexors
 Muscle mass ventral to limb bones
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Limb Muscles
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Figure 11.4e
Interactions of Skeletal Muscles in the Body



A muscle cannot reverse the movement it
produces
Another muscle must undo the action
Muscles with opposite actions lie on opposite
sides of a joint
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Muscles Classified into Several Functional Groups

Prime mover (agonist)

Antagonist

Synergist – helps the prime mover
 Has major responsibility for a certain movement
 Opposes or reverses a movement
 By adding extra force
 By reducing undesirable movements
 Fixator
 A type of synergist that holds a bone firmly in place
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Muscle Compartments of the Limbs


Dense fibrous connective tissue divides limb
muscles into compartments
Muscles in opposing compartments are
 Agonist and antagonist pairs

Each compartment is innervated by a single nerve
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Muscle Compartments of Arm and Forearm

The upper limb has anterior and posterior
compartments
 Anterior arm compartment muscles
 Flex the shoulder or arm
 Innervation is the musculocutaneous nerve
 Anterior forearm compartment muscles
 Flex the wrist and digits
 Innervation is the median or ulnar nerve
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Muscle Compartments of the Arm and Forearm
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Figure 11.5a
Muscle Compartments of the Arm and Forearm
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Figure 11.5b
Muscle Compartments of the Thigh

Posterior compartment muscles

Anterior compartment muscles

Medial compartment
 Extend the hip and flex the knee
 Innervation is the tibial branch of the sciatic nerve
 Flex the hip and extend the knee
 Innervation is the femoral nerve
 Adduct the thigh
 Innervation is the obturator nerve
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Compartments of the Leg

Posterior compartment muscles

Anterior compartment muscles

Lateral compartment muscles
 Contains digital and plantar flexors
 Innervation is the tibial nerve
 Contains digital extensors and dorsiflexors
 Innervation is the deep fibular nerve
 Plantar flex and evert the foot
 Innervation is the superficial fibular nerve
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Muscle Compartments of the Thigh and Leg
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Figure 11.6a
Muscle Compartments of the Thigh and Leg
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Figure 11.6b
Naming the Skeletal Muscles

Location
 Example – the brachialis is located on the arm

Shape
 Example – the deltoid is triangular

Relative size
 Maximus, minimus, and longus indicate size
 Example – gluteus maximus and gluteus minimus
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Naming the Skeletal Muscles

Direction of fascicles and muscle fibers
 Name tells direction in which fibers run
 Example – rectus abdominis and transversus
abdominis

Location of attachments – name reveals point of
origin and insertion
 Example – brachioradialis
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Naming the Skeletal Muscles

Number of origins
 Two, three, or four origins
 Indicated by the words biceps, triceps, and
quadriceps

Action
 The action is part of the muscle’s name
 Indicates type of muscle movement
 Flexor, extensor, adductor, or abductor
Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings
PowerPoint® Lecture Slides
prepared by Leslie Hendon,
University of Alabama,
Birmingham
11
HUMAN
ANATOMY
PART 2
Muscles of
the Body
fifth edition
MARIEB | MALLATT | WILHELM
Copyright © 2008 Pearson Education, Inc.,
publishing as Benjamin Cummings
Superficial Muscles of the Body – Anterior View
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Figure 11.7a
Superficial Muscles of the Body – Posterior View
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Figure 11.7b
Muscles of the Head – Facial Expression

Muscles of facial expression
 Lie in the face and scalp
 Thin and variable in shape
 Often insert in the skin – not on bones
 Innervated by cranial nerve VII – the facial nerve
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Muscles of the Head – Facial Expression
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Figure 11.8
Muscles Mastication and Tongue Movement

Four main pairs of muscles involved in
mastication
 Innervated by mandibular division of the trigeminal
nerve (cranial nerve V)
 Prime movers of jaw closure
 Masseter and temporalis
 Side-to-side movement
 Pterygoid muscles
 Compression of cheeks
 Buccinator muscles
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Muscles of Mastication and Tongue Movement
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Figure 11.9a, b
Muscles Mastication and Tongue Movement


Extrinsic muscles of the tongue
Move tongue
 Laterally
 Anteriorly
 Posteriorly

All innervated by cranial nerve XII – the
hypoglossal nerve
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Muscles of Mastication and Tongue Movement
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Figure 11.9c
Muscles of the Anterior Neck and Throat – Swallowing


The neck is divided into anterior and posterior
triangles
Anterior triangle
 Divided into suprahyoid and infrahyoid muscles
 Participate in swallowing

Pharyngeal constrictors
 Squeeze food into the esophagus
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Muscles of the Anterior Neck and Throat – Swallowing
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Figure 11.10a
Muscles of the Anterior Neck and Throat – Swallowing
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Figure 11.10b
Muscles of the Neck and Vertebral Column

Head movement
 Sternocleidomastoid
 Splenius capitis and splenius cervicis
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Figure 11.11a
Muscles of the Neck and Vertebral Column
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Figure 11.11b
Muscles of the Neck and Vertebral Column

Trunk extension
 Deep muscles of the back
 Maintain normal curvatures of the spine
 Form a column from sacrum to the skull
 Erector spinae group
 Largest of the deep back muscles
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Muscles of the Neck and Vertebral Column
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Figure 11.11d
Deep Muscles of the Thorax – Breathing

Deep muscles provide movements for breathing
 External intercostal muscles
 Lift the ribcage
 Internal intercostal muscles
 Aid expiration during heavy breathing
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Deep Muscles of the Thorax – Breathing

Diaphragm
 Most important muscle of respiration
 Flattens as it contracts
 Increases the volume of the thoracic cavity
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Deep Muscles of the Thorax – Breathing
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Figure 11.12a
Deep Muscles of the Thorax – Breathing
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Figure 11.12b
Muscles of the Abdominal Wall

Lateral and anterior abdominal wall
 Formed from three flat muscle sheets
 External oblique
 Internal oblique
 Transversus abdominis
 Fourth muscle pair
 Rectus abdominis
 Inserts at the linea alba
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Muscles of the Abdominal Wall
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Figure 11.13a
Muscles of the Abdominal Wall
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Figure 11.13b
Muscles of the Pelvic Floor


Pelvic floor (pelvic diaphragm)
Sheet of two muscles
 Both support pelvic organs
 Levator ani
 Formed from iliococcygeus, puborectalis, and
pubococcygeus
 Coccygeus
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Muscles of the Pelvic Floor
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Figure 11.14a
Muscles of the Perineum


Inferior to the muscles of the pelvic floor
Urogenital diaphragm formed from
 Sphincter urethrae and the deep transverse
perineus
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Figure 11.14b
Muscles of the Perineum

Muscles of the superficial perineal space
 Ischiocavernosus
 Bulbospongiosus
 Superficial transverse perineus
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Muscles of the Perineum
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Figure 11.14c
Superficial Muscles of the Anterior Thorax

Movements of the scapula
 Pectoralis major
 Pectoralis minor
 Serratus anterior
 Subclavius
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Superficial Muscles of the Anterior Thorax
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Figure 11.15a
Superficial Muscles of the Posterior Thorax

Movements of the scapula
 Trapezius
 Levator scapulae
 Rhomboid major
 Rhomboid minor
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Superficial Muscles of the Posterior Thorax
PLAY
Rotator cuff muscles: an overview (a)
PLAY
Rotator cuff muscles: an overview (b)
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Figure 11.15b
Muscles Crossing the Shoulder Joint

Movements of the arm
 Deltoid
 Pectoralis major
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Figure 11.16a
Muscles Crossing the Shoulder Joint

Movements of the arm
 Latissimus dorsi
 Supraspinatus
 Infraspinatus
 Teres minor
 Teres major
 Coracobrachialis
 Subscapularis
PLAY
Movement at the glenohumeral
joint: an overview
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Figure 11.16b
Muscles Crossing the Elbow Joint
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Figure 11.16a
Muscles Crossing the Elbow Joint

Posterior muscles – extensors of the forearm

Anterior muscles – flexors of the forearm
 Triceps brachii
 Anconeus
 Biceps brachii – also supinates the forearm
 Brachialis
 Brachioradialis
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Muscles of the Forearm

Movements of the wrist, hand, and fingers
 Tendons are anchored by
 Flexor and extensor retinacula
 Most forearm muscles arise from the distal
humerus
 Movements at the wrist include
 Flexion, extension, abduction, and adduction
 Wrist and fingers are “operated” by muscles in the
forearm
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Muscles of the Forearm

Flexors
 Anterior flexor compartment
 Innervated by median and ulnar nerves

Originate from a common tendon
 Medial epicondyle of the humerus
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Superficial Anterior Muscles of the Forearm





Pronator teres
Flexor carpi radialis
Palmaris longus
Flexor carpi ulnaris
Flexor digitorum
superficialis
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Figure 11.17a
Deep Anterior Muscles of the Forearm



Flexor pollicis longus
Flexor digitorum profundus
Pronator quadratus
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Deep Anterior Muscles of the Forearm
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Figure 11.17b, c
Muscles of the Forearm

Extensors
 Posterior compartment of the forearm
 Innervated by the radial nerve
 Originate at a common tendon
 Lateral epicondyle of the humerus
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Superficial Posterior Muscles of the Forearm





Brachioradialis – flexes
forearm
Extensor carpi radialis
longus
Extensor carpi radialis
brevis
Extensor digitorum
Extensor carpi ulnaris
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Figure 11.18a
Deep Posterior Muscles of the Forearm




Supinator
Abductor pollicis
longus
Extensor pollicis brevis
and longus
Extensor indicus
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Figure 11.18b
Intrinsic Muscles of the Hand




Fine movement of the fingers
All located in the palm
Control precise movements
Include muscles of
 Adduction, abduction, and opposition
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Intrinsic Muscles of the Hand

Thenar muscles – ball of thumb

Hypothenar muscles
PLAY
 Abductor pollicis brevis
 Flexor pollicis brevis
 Opponens pollicis
 Adductor pollicis
 Abductor digiti minimi
 Flexor digiti minimi
 Opponens pollicis
Muscles that act on the wrist and fingers: an overview
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Intrinsic Muscles of the Hand
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Figure 11.19a
Intrinsic Muscles of the Hand

Midpalmar muscles
 Lumbricals
 Palmar interossei
 Dorsal interossei
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Figure 11.19b
Intrinsic Muscles of the Hand
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Figure 11.19c
Muscles Crossing the Hip and Knee Joints

Thigh and leg movements
 Anterior muscles
 Flex the thigh and extend the leg at the knee
 Posterior muscles
 Extend the thigh and flex the leg
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Muscles Crossing the Hip and Knee Joints

Thigh and leg movements
 Adductor muscles – on medial aspect of thigh
 Adduct the thigh only
 Deep fascia of the thigh
 Surrounds and encloses all three groups
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Muscles Crossing the Hip and Knee Joints

Movements at the hip joint
 Muscles that flex the thigh
 Originate on vertebral column or pelvis
 Muscles that extend the thigh
 Arise posterior to the hip joint
 Adductors originate medial to the hip joint
 Abductors originate lateral to the hip joint
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Anterior and Medial Muscles

Origin on pelvis or vertebral column




Iliacus
Psoas major
Sartorius
Muscles of the medial compartment





Adductor longus
Adductor brevis
Adductor magnus
Pectineus
Gracilis
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Anterior and Medial Muscles
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Figure 11.20a
Muscles of the Anterior Compartment of the Thigh

Quadriceps femoris
 Has four separate heads
 Has a common insertion at the quadriceps tendon
 Powerful knee extensors
 Rectus femoris
 Vastus lateralis
 Vastus medialis
 Vastus intermedius
 Tensor fasciae latae
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Muscles of the Anterior Compartment of the Thigh
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Figure 11.20a
Posterior Muscles


PLAY
Origin on pelvis or sacrum
 Gluteus maximus
 Gluteus medius
 Gluteus minimus
Lateral rotators
 Piriformis
 Obturator externus
 Obturator internus
 Superior and inferior gemellus
 Quadratus femoris
Movement at the hip joint: an overview
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Posterior Muscles
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Figure 11.21b
Muscles of the Posterior Compartment of the Thigh




Hamstrings
Biceps femoris
Semitendinosus
Semimembranosus
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Figure 11.21a
Muscles of the Leg

Fascia lata of the leg surrounds muscles
 Tightly binds muscles
 Prevents swelling during exercise
 Aids venous return
 Divides leg into three compartments

Tendons are held in place by
 Extensor, fibular, and flexor retinacula

Muscle movement at ankle and intertarsal joints
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Muscles of the Anterior Compartment




PLAY
Tibialis anterior
Extensor digitorum longus
Fibularis (peroneus) tertius
Extensor hallucis longus
Muscles of the ankle and foot (b)
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Figure 11.22a
Muscles of the Lateral Compartment





PLAY
Fibularis (peroneus)
longus
Fibularis (peroneus)
brevis
Flexor hallucis
longus
Extensor hallucis
longus
Fibularis tertius
Muscles of the ankle and foot (c)
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Figure 11.23a
Muscles of the Lateral Compartment
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Figure 11.23b, c
Muscles of the Posterior Compartment

Superficial muscles
 Triceps surae
 Gastrocnemius
 Soleus
 Plantaris
PLAY
Muscles that act on the ankle and foot: an overview
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Muscles of the Posterior Compartment
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Figure 11.24a, b
Muscles of the Posterior Compartment

Deep muscles
 Popliteus
 Flexor digitorum longus
 Flexor hallucis longus
 Tibialis posterior
PLAY
Muscles of the ankle and foot (a)
PLAY
Muscles of the ankle and foot (d)
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Figure 11.24c
Intrinsic Muscles of the Foot

Toe movement and foot support
 Help to flex, extend, abduct, and adduct the toes
 Support the arches of the foot
 Single muscle on dorsal aspect of the foot
 Many muscles on the plantar aspect
Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings
Intrinsic Muscles of the Foot

Muscle on the
dorsum of the foot
 Extensor digitorum

brevis
Muscles on the sole
of the foot
 First layer
 Flexor digitorum
brevis
 Abductor hallucis
 Abductor digiti
minimi
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Figure 11.25a
Intrinsic Muscles of the Foot

Second layer
 Flexor accessorius
 Lumbricals
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Figure 11.25b
Intrinsic Muscles of the Foot

Third layer
 Flexor hallucis brevis
 Adductor hallucis
 Flexor digiti minimi
brevis

Fourth layer
 Plantar and dorsal
interossei
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Figure 11.25c
Intrinsic Muscles of the Foot
Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 11.25d, e
Surface Anatomy


Palpation – feeling internal structures through the
skin
“Living anatomy” – provides information about
 Palpation of arterial pulses
 Skeleton, muscles, and blood vessels
 Sounds of the heart and lungs
 Where to give injections
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The Head

Cranium – selected structures felt through the skin
 Superciliary arches
 External occipital protuberance
 Mastoid process
 Temporalis muscle – at temple region
 Frontalis muscle
 Feel wrinkling of the forehead when eyebrows are
raised
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Surface Anatomy of Lateral Aspect of the Head
Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 11.26
The Head

Face – selected structures felt through the skin
 Lacrimal fossa
 Root and bridge of the nose
 Auricle of the ear
 Zygomatic arch
 Masseter muscle
 Mandible
 Temporomandibular joint
Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings
The Neck

Skeletal landmarks
 Spinous processes of cervical vertebrae
 C7 is particularly prominent (vertebra prominens)
 Hyoid bone – in the anterior, superior neck
 Laryngeal prominence – the “Adam’s Apple”
 Cricoid cartilage – inferior to the laryngeal
prominence
 Jugular notch – depression in the superior part of
the sternum
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The Neck
Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 11.27
Muscles of the Neck

Sternocleidomastoid – most prominent neck
muscle
 Sternal head
 Clavicular head

Deep to the sternocleidomastoid
 Common carotid artery
 Internal jugular vein

Trapezius – posterior aspect of the neck
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Triangles of the Neck

The sternocleidomastoid muscles divide
the neck
 Anterior triangle
 Posterior triangle
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Figure 11.28a
Triangles of the Neck
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Figure 11.28b
The Trunk

The trunk consists of the
 Thorax
 Abdomen
 Pelvis and perineum
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The Thorax

Sternum – portions felt through the skin
 Manubrium, xiphoid process, and sternal angle


Midaxillary line – line from the center of the axilla
onto the lateral thoracic wall
Midclavicular line – vertical line from midpoint of
the clavicle to the groin
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Muscles of the Thorax


Pectoralis major
Serratus anterior
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The Anterior Thorax and Abdomen
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Figure 11.29
The Abdomen

Structures felt through the skin
 Iliac crest
 Anterior superior iliac spine
 Inguinal ligament
 Runs medially from anterior superior iliac spine to
the pubic tubercle
 Pubic crest
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Inguinal Hernia
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Figure 11.30
Muscles and other Abdominal Surface Features

Linea alba
 The “white line” extending from xiphoid process to
the pubic symphysis

Rectus abdominis
 Linea semilunaris – lateral margin of rectus
abdominis
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The Pelvis and Perineum

Four bony structures define the perineum
 Pubic symphysis
 Two ischial tuberosities
 Coccyx
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The Back




Posterior median furrow – vertical groove along
the midline
Spinous processes of vertebrae
Spine of the scapula
 Medial end is opposite T3
Medial border of the scapula
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The Back




Inferior angle of the scapula
Iliac crests
 Supracristal line – intersects L4
Sacrum – superior to cleft in the buttocks
Coccyx – posterior to the anus
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Surface Anatomy of the Back
Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 11.31a
Muscles of the Back



Trapezius
Latissimus dorsi
Erector spinae
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Surface Anatomy of the Back
Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 11.31b
Upper Limb and Shoulder

The Axilla
 Base of the axilla – where armpit hair grows
 Deep to the axilla – axillary lymph nodes and
blood vessels
 Anterior axillary fold – pectoralis major
 Posterior axillary fold –latissimus dorsi and teres
major
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Shoulder and Arm
Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 11.32a, b
The Shoulder



Acromion – lateral end
of the spine of the
scapula
Acromioclavicular
joint
Deltoid muscle
 Covers the greater
tubercle of the
humerus
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Figure 11.33
The Arm


The region between the shoulder and elbow
Humerus
 Palpated through skin along its entire length


Biceps brachii
Medial bicipital groove
 The medial boundary of the biceps brachii

Triceps brachii
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The Arm
Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 11.34
The Elbow

Lateral and medial epicondyles of the humerus
 Ulnar nerve – “funny bone” runs across medial
epicondyle


Olecranon process of the ulna
Cubital fossa – (antecubital fossa)
 Forms anterior surface of forearm
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The Anterior Surface of the Forearm and Fist
Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 11.35a
Forearm

Bones
 Ulna – palpate entire length
 Styloid process and head – distal end

Radius – partly covered in muscle
 Head of the radius – proximal end
 Styloid process – distal end
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Muscles of the Forearm

Flexor muscles – anterior forearm
 Flexor carpi radialis
 Palmaris longus
 This muscle is absent in about 30% of people

Extensor muscles – posterior forearm
Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings
Other Structures of the Forearm

Anatomical snuff box bordered by
 Extensor pollicis brevis
 Extensor pollicis longus
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The Hand

Dorsum of hand
 Dorsal venous network
 Tendons of extensor digitorum

Palmar surface
 Thenar eminence (not labeled on figure 11.35b)
 Hypothenar eminence (see figure 11.17a–c )
 Pisiform bone
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The Dorsum of the Hand
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Figure 11.36
Gluteal Region




Iliac crests
Posterior superior iliac spine
Sacroiliac joint
Prominences of the buttocks
 “Cheeks” of the buttocks
 Formed from subcutaneous fat and the gluteal
muscles
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The Gluteal Region
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Figure 11.37
Lower Limb and Gluteal Region

Natal cleft (gluteal cleft)
 Vertical midline groove between “cheeks”

Gluteal fold
 Horizontal fold below each “cheek”


Ischial tuberosities
Greater trochanter of the femur
 Located at the lateral hip
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Lower Limb and Gluteal Region
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Figure 11.38a
Thigh



Medial and lateral condyles of the femur
Patella
Three groups of muscles
 Quadriceps femoris – anterior thigh
 Vastus lateralis – injection site
 Adductors – medial thigh
 Hamstrings – posterior thigh
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Thigh
Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 11.38b
The Thigh


The Femoral Triangle
 Superior border – inguinal ligament
 Inferior borders
 Sartorius
 Adductor longus
Popliteal fossa
 Diamond-shaped hollow on posterior knee
 Defined by borders of “hamstring” tendons and
gastrocnemius
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Leg and Foot


Palpate patella to find the patellar ligament
Structures of the proximal leg
 Tibial tuberosity
 Lateral and medial condyles of the tibia
 Head of the fibula

Structures of the distal leg
 Medial malleolus
 Lateral malleolus
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Leg and Foot
Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 11.40a, c
Muscle Groups of the Leg

Posterior calf muscles
 Gastrocnemius and soleus
 Calcaneal tendon – inferior end of the soleus and
gastrocnemius

Anterior compartment muscles
 Tibialis anterior
 Extensor digitorum
 Fibularis
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Muscle Groups of the Leg
Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 11.41
Foot

Tendons on the dorsal surface of the foot
 Extensor digitorum longus tendon
 Extensor hallucis longus
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Foot
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Figure 11.40d