Module 1: Introduction to Anatomy + Head and Neck Flashcards
(150 cards)
1
Q
What is the Anatomical position?
A
- Standing upright
- Facing forward at observer
- Mouth is closed and facial expression is neutral
- Arms by the side & Palms of hands facing forwards 5. Feet flat on the floor & close together
- Toes pointing forwards
2
Q
What are the anatomical regions of the body?
A
The human body is made up of many regions
- Cranial = skull
- Cephalic = head
- Cervical = neck
- Thoracic = chest
3
Q
What is the red square?
A
Axial Body: Centre body mass
- Midline structures
- Head, neck and trunk
4
Q
What body do the blue regions belong to?
A
Appendicular Body = Limbs off trunk
• Upper & Lower limbs
5
Q
Directional term: Superior
A
Towards the head (cranial)
These terms (superior and inferior) are specific to features involving the axial body, or on different limbs
6
Q
Directional term: Inferior
A
Towards the feet (caudal)
These terms (superior and inferior) are specific to features involving the axial body, or on different limbs
7
Q
Directional term: proximal
A
Closer to its specific origin
i.e. closer to where the appendicular body structure attaches to the axial body
These terms (distal and proximal) are specific to features involving the appendicular body, and on the same limb
8
Q
Directional term: Distal
A
- Further from its specific origin
- i.e. further from where the appendicular body structure attaches to the axial body
- These terms (distal and proximal) are specific to features involving the appendicular body, and on the same limb
9
Q
Directional term: (white box)
A
Posterior (dorsal)
• Behind; towards the back surface
10
Q
Directional term: (white box)
A
Anterior (ventral)
• In front of; towards the front surface
11
Q
Directional Term: red box
A
Medial:
Towards or at the midline
12
Q
Directional term: red box
A
Lateral:
Away from the midline
13
Q
Directional term: red box
A
Superficial:
Nearest to the skin (body surface)
14
Q
Directional Term: red box
A
Deep:
Furthest from the skin (body surface)
15
Q
What is an anatomical plane?
A
Plane: Imaginary lines/flat surfaces that pass through the body
“The body can be cut along a plane (imaginary line), to produce a specific type of section”
A term used to reference perspective of prosections
16
Q
What is an anatomical section
A
Section: the surface of the slice that results when the body is cut along the plane passing through
“The body can be cut along a plane (imaginary line), to produce a specific type of section”
A term used to reference perspective of prosections
17
Q
What plane is this?
A
The Sagittal Plane = Divides the body into left and right sides
- Mid-sagittal plane = equal halves
- Para-sagittal plane = unequal halves
18
Q
What anatomical plane is this?
A
The Transverse Plane = Divides the body into upper and lower portions
• Transverse (horizontal) plane = divides the body into superior (upper) and Inferior (lower) portions
19
Q
What anatomical plane is this?
A
The Frontal Plane = Divides the body into anterior and posterior portions
Frontal (coronal) plane = divides the body into anterior (front) and posterior (back) portions
20
Q
Connective tissue
A
= contains a variety of cells & proteins suspended in extracellular matrix
21
Q
Connective Tissue
A
= contains a variety of cells & proteins suspended in extracellular matrix
22
Q
Connective Tissue Function
A
Functions:
• Establishes structural framework
• Supports/provides interconnections between primary tissue types • Provides medium for diffusion of nutrients & waste products
• Stores energy reserves & defends against infection
23
Q
Connective Tissue Type
A
3 Types:
• General CT (fibrous): Loose, or Dense CT (tendons & ligaments) • Fluid CT: Lymph or Blood
• Supportive: Bone or Cartilage
24
Q
Tendons Vs Ligaments
A
Ligaments
- Link bones at or near the joint
- Stabilise & maintain tension at joint
- Less organised bundles
- ATTACH BONE TO BONE
Tendons
- Slightly elasticstretch by 6-15%
- Vascular supply sparse, not negligible
- Large tensile forces
- Fibres aligned with direction of tension • ATTACHMUSCLETOBONE
25
What is (red box)?
Liagment
26
What is (red box)?
Tendon
27
Red box: Compact/Cortical/Dense
Green box: Spongy/Cancellous/ Trabecular
28
Cell phases from stem cell to bone cell
29
Inorganic vs organic bone phase
30
What do joints provide?
• Joints provide both Stability & Mobility
* Locked joint is most stable
* Unlocked joint is most mobile
31
What are the Joint classifications (class)?
Structural vs functional class
## Footnote
**Functional Classifications:** Refers to the range of motion at an articulation
* Immobile (synarthrosis) = no movement
* Partly mobile (amphiarthrosis) = little movement
* Freely mobile (diarthrosis) = wide range of movement
**Structural Classifications:** Refers to what links the bones together
* Bony = complete fusion of two bones
* Fibrous = held together by dense collagen fibres
* Cartilaginous = held together by cartilage
• Synovial = contain a joint space held together by joint capsule
*Each joint must compromise strength and stability for its range of motion*
32
Which Joint classification is this (range of movement)?
• Synarthrosis = Immobile
33
Which Joint classification is this (range of movement)?
Amphiarthrosis = slightly moveable
34
Which Joint classification is this (range of movement)?
Diarthrosis = Freely moveable
35
Joint classification; Structural classification - What links the bones?
Bony = bone fusion
Fibrous = dense collagen fibres
Cartilaginous = Hyaline or firbo-cartilage
Synovial = ligaments and synovial spce
36
What kind of joint is this?
Fibrous Joints; Sutures
* Restricted to skull; bone have interlocking edges
* Bone linked by thin layer of fibrous, dense connective tissue (can be replaced by bone later in life)
* Immoveable
37
What kind of joint is this?
Fibrous Joints; Syndesmosis
* Two parallel bones are held together by collagenous fibres that are longer than those found in sutures
* Forms a band-like ligament (i.e. between distal tibia and fibula)
* May be slightly moveable
38
What kind of joints are these?
Cartilaginous Joints; Symphysis
* Bones joined together by pad of fibrocartilage
* No joint space
* Compressible, strong & flexible
* Limited movement possible
39
Assumed Knowledge about cartilage
* Avascular and lacks nerve innervation (limited repair)
* Capable of bearing and distributing weight
* Covered by perichondrium except at articular surfaces
40
What kind of joints are these?
Cartilaginous Joints; Synchondrosis
* Joint separated by a plate of hyaline cartilage
* No joint space
* Most exist between ossification centres; often ossify
* Limited movement possible
41
What kind of joint is this?
Synovial Joints; Most Common
* Simple, Compound and Complex
* Articulating bones are separated by joint cavity; enclosed in a fibrous capsule
* Articulating surfaces lined by hyaline cartilage
* Synovial membrane lining inner surface of joint capsule; secretes synovial fluid into joint cavity
* Joint stability provided by fibrous capsule, internal and external accessory ligaments
42
Synovial joints; classifications and types
1. Plane joint; flat articular surfaces, nonaxial movement (gliding)
* Examples: intercarpal joints, intertarsal joints, joints between vertebral articular surfaces
2. Hinge joint; uniaxial movement (flexion and extension along medial/lateral axis)
* Examples: elbow joints, interphalangeal joints
3. Pivot joint; uniaxial movement (rotation along the vertical axis)
* Examples: proximal radioulnar joints, atlantoaxial joint
4. Condylar joint; biaxial movement ( flexion and extension along medial/lateral axis; adduction and abduction along anterior/posterior axis)
* Examples: metacarpophalangeal (knuckle) joints, wrist joints
5. Saddle joint; biaxial movement (adduction and abduction along medial/lateral axis; flexion and extension along anterior/posterior axis)
* Example: carpometacarpal joints of the thumb
6. Ball and socket joint; Multiaxial movement (flexion and extension along medial/lateral axis; adduction and abduction along the anterior/posterior axis; rotation along vertical axis)
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Flexion
Decreasing angle of joint
"Bringing bones together"
44
Extension
Increasing angle of joint
"straightening motion"
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Hyperextension
Increasing angle of joint greater than 180 degrees
"difficult/uncommon"
46
Abduction
lateral movement away from the midline
"star jump"
47
Adduction
Medial movement towards the midline
"adding (+) to your body"
48
Circumduction
Circular movement combining all angular movements
"shape of a cone"
49
What type of muscle contraction is this?
Concentric action: muscles develop tension and shorten
* Limb/trunk segments “overcome forces” that would otherwise cause muscle lengthening
* Muscles work against a load that CAN be lifted
50
What type of muscle contraction is this?
Eccentric action: muscles develop tension but lengthen
* Limb/trunk segments actively “give way” to forces, lengthening muscles
* Muscles work against a load that CANNOT be lifted
51
What type of muscle contraction is this?
Isometric action: muscles develop tension but remain at same length
* Limb/trunk segments are “maintained stationary” despite forces that would otherwise cause muscle lengthening
* Muscles work against a load that CANNOT be lifted but HOLDS POSITION
52
Agonist
Muscles which, when contracting concentrically, cause joint motion
* PRIME Movers: muscle(s) that have the greatest contribution to joint movement
* ASSISTANT Movers: contribute significantly less to movement
53
Antagonist
Contralateral muscles, located on the OPPOSITE side of the joint from the agonist. Work in conjunction with the agonist by relaxing and allowing movement
54
Which box is this agonist and which is the antagonist?
55
Which box is the agonist and which is the antagonist?
56
Fibrous Joint
Connective bone with dense fibrous connective tissue
Generally don't move (synarthrotic)
Types include: sutures and syndesmoses
57
Cartilaginous Joint
• Unite bone using cartilage
* Slightly moveable (amphiarthrotic)
* Types include: Symphyses & Syncondroses
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Synovial Joint
* Freely moveable (diarthrotic)
* 6 joint major features:
* Articular cartilage
* Joint cavity
* Synovial Membrane
* Synovial fluid
* Fibrous capsule
* External ligaments Nerve and vessels
59
How do we classify synovial joints?
* Synovial joints can be classified on the basis of:
* Structural shape
* Plane/Gliding
* Hinge
* Pivot
* Condyloid/Ellipsoid
* Saddle
* Ball and socket
* Axes movement - 'an axis that a body part rotates around'
* Nonaxial
* Uniaxial
* Biaxial
* Multiaxial
60
What plane and axis of movement/rotation is this?
Plane: Sagittal
Axis: Mediolateral
Movement: In the sagittal plane, the shoulder flexes/extends on the mediolateral axis
61
What plane and axis of movement/rotation is this?
* Plane: Frontal/Coronal
* Axis: Anteroposterior
* Movement: In the frontal plane, the shoulder abducts/adducts on the anteroposterior axis
62
What plane and axis of movement/rotation is this?
* Plane: transverse/horizonral
* Axis: vertical
* Movement: In the transverse plane, the shoulder horizontally adducts/abducts on the vertical axis
63
Synovial Joints: Gliding joints
* Articular surface are extremely flat
* Allow short gliding or sliding movements
* Nonaxial
* Example: Joints in hand (intercapal joints)
64
Synovial joint: Hinge joint
* A cylindrical projection of one bone fits into a trough-shaped surface of another bone
* Motion is along a single plane
* Example: Joints between the humerus and radius (elbow)
65
Synovial Joint: Pivot Joint
* The rounded end of one bone protrudes into a sleeve composed of bone and/or ligaments
* Allows rotation along the axis of the bone
* Uniaxial
* Example: Joints between radius and ulna
66
Synovial Joints: Condylar Joint
* Oval-shaped articular surface of one bone fits into a complimentary depression on another bone
* Permits significant movement in 2 planes
* Biaxial
* Example: Joints between metacarpals and phalanges
67
Synovial Joint: Saddle Joint
* Each articular surface has both concave and convex areas
* Permits significant movement in 2 planes
* Biaxial
* Example: thumb carpometacarpal joint
68
Synovial Joints: Ball and Socket Joint
* The Spherical head of one bone articulates with a cup-shaped socket of another bone
* The most freely moveable of synovial joints
* Multiaxial
* Example: Hip and Shoulder
69
What basic movements occur on sagittal plane and mediolateral axis?
* Flexion
* Extension
* Hyperextension
70
What basic movements occur on the frontal/coronal plane and anteroposterior axis?
* Adduction
* Abduction
71
What basic movements occur on the transverse/horizontal plane and vertical axis?
* Rotation
72
Specialised movements?
* Lateral flexion
* Upward/downward rotation and depression/elevation
* Horizontal flexion/adduction and extension/abduction
* Pronation vs supination
* Radial deviation vs ulnar deviation
* Dorsiflexion vs plantar flexion
* Inversion vs eversion
73
How many bones in the axial skeleton?
* Longitudinal Axis
* Head, thorax, vertebral column
* Typicall 80 bones (approx 40%)
74
How many bones in the appendicular skeleton?
* Limbs and supporting girdles
* Typically 126 bones
* approx 60%
75
What are the 5 types of bones in the human body?
1. Long bones (femur, leg, arms, finger bones)
2. Short bones
3. Sesamoid bone (patela, knee cap)
4. Irregular bones (vertebrae)
5. Flat bones
76
paired vs unpaired bones
* paired bone; one on each side
* unpaired bones; usually along midline of the body
77
Total number of bones in the adult human body?
206
78
Bones that make up the skull?
1. Cranium
* Neurocranium (top red and purple)
* "neurocranium" = "hold the brain"
* Facial domed part
* Covers cranial cavity & brain
* Paired bones include: Parietal & Temporal
* Unpaired bone include: Frontal, Occipital & Sphenoid
* Basicranium (blue and side yellow part)
* Floor of cranial cavity
* Frontal, Temporal, Occipital, Sphenoid & Ethmoid
1. Facial skeleton
* Viscerocranium
* Gives face shape and structure
* Orbit & Nasal cavity, Tooth support
* Paired bones include: Nasal, Palatine, Lacrimal (inside eye; helps with secretion of tears), Zygomatic, Maxillary, Inferior Nasal conchae
* Unpaired bones include: Vomer (separates two nasal passages), mandible (jaw)
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Articulations of the neurocranium?
* Coronal suture
* Attaches frontal bone to parietal bones
* Sagittal suture
* Attaches parietal bones together
* Lambdoid suture
* Attaches occipital bone to parietal bones
* Squamous suture (one on each side)
* Attaches temporal bone to parietal bone
80
What is the functional + structural classification of cranial sutures?
* Immoveable (synarthrosis) fibrous joints
* Dense connective tissue
* Forms boundaries between bones
81
Name the bones and sutures.
82
Name the bones and sutures.
83
What is circled in yellow?
* Pterion
* Combination of sutures where the Parietal, Frontal, Temporal and the Sphenoid bones join
84
The cranium articulations on an infant skull
* Head vs Brain Growth
* 1st year = 90% of adult brain size
* 6th year = 95% of adult brain size
* 7th year = 100% of adult brain size
* Ext. cranium continues to puberty
* Metopic suture is by 7 years of age.
* Fontanelles allow movement for rapid brain growth (soft spots)
* Anterior Fontanelle = 1-2 years
* Posterior Fontanelle = 3 months
85
What are the stages of the metopic suture fusing?
* The frontal bone divided vertically at birth by metopic suture
* metopic suture usually fuses in early childhood
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What is metopism?
* Rare condition where metopic suture is persistent through life
* Majority of cases result in no significant medical outcome
* Higher percentage of cases in Italian heritage than African heritage.
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What is craniosynostosis?
* Altered suture fusion; a condition where cranial suture fuse prematurely.
* Reduced volume for brain growth and increased intracranial pressure
* Possible outcomes include
* Abnormal cranial features and shape
* Impaired cognitive and behaviour development
* Sleeping and visual impairment
88
What makes up the basicranium of the cranium?
* The basicranium is the floor of the cranial cavity
* Includes the inferior aspect of frontal, occipital, temporal and sphenoid bone + the ethmoid bone
* Ethmoid bone is perforated because it connects nose and brain and hols for nerves (sense of smell)
* Brain stem and spinal cord sit in foramen magnum
89
Name the bones.
The Floor of the Cranial Cavity
• Inferior aspect of Frontal, Occipital, Temporal & Sphenoid bone + the Ethmoid bone
90
Name the fossa of the basicranium
3 Basins that make up the cranial floor
* Anterior Fossa sits in frontal lobes
* Middle Fossa sits in temporal lobes
* Posterior Fossa sits in cerebellum
91
What paired bones is part of the viscerocranium?
* Facial bones dominate the anterior aspect of the skull
* Paired bones;
* Nasal bones: Bridge support
* Lacrimal bones: medial eye socket
* Palatine: posterior hard palate and orbital floor
* Zygomatic: lateral orbit and prominent cheek bone
* Maxillae: support teeth and inferior orbital rim
* Inferior Nasal Conchae: air turbulence
92
What unpaired bones are part of the viscerocranium?
Unpaired:
* Vomer: inferior bony nasal septum
* Mandible: Lower jaw
* Ethmoid: Separates nasal passage & forms medial orbit
* Sphenoid: Greater & Lesser wings; posterior wall of orbit
93
Name the bones of the viscerocranium
94
What is the orbit of the facial skeleton? What is it formed by?
* The orbit is the cavity in the skull that houses the eye (the eye socket)
* Formed by;
* Superior wall (roof) = Frontal bone
* Medial wall = Ethmoid and Lacrimal
* Inferior wall (floor) = Maxilla and zygomatic
* Posterior wall = sphenoid
95
What parts of the orbit are labelled and what are they made of?
* Superior wall (roof) = Frontal bone
* Medial wall = Ethmoid & Lacrimal
* Inferior wall (floor) = Maxilla & Zygomatic
* Lateral wall = Zygomatic
* Posterior wall = Sphenoid
96
What bone is this?
The sphenoid bone
97
Label the paranasal sinuses? How many of each?
* These are weight savers
98
Where do the paranasal sinuses drain into?
* The nasal cavity
99
Name the structure
100
Label the paranasal sinuses
1. Frontal sinuses
2. Ethmoid
3. Sphenoid bone
4. Maxilla
101
The mandible; articulations for mastication
What are the subdivisions of the mandible?
What is their function?
* The Mandible contains two subdivisions:
* Horizontal Body
* Ascending Rami
* Horizontal Body:
* Supports teeth at alveolar part
* Contains several foramen for nerves/vasculature
* Mental foramen (external; chin/lip sensation
* Mandibular foramen (internal; lower tooth sensation), nerves come through here
* Ascending Rami
* Forms part of the Temporomandibular Joint (TMJ)
* Mandibular condyle articulates with the Temporal bone; this is a condular joint
102
Label the Mandible
* Mandibular condyle articulates with temporal bone
* The coronoid process goes under the zygomatic bone
* Nerves go through the mental foramen as well
103
What joint is circled in red?
What is the function of this joint?
* The temperormandibular joint
* Essential for chewing and speaking
104
What vertebrae make up the neck?
What movement occurs at the neck?
What size are the vertebrae?
* 7 cervical vertebra make up the neck (C1 to C7) containing a transverse foramen
* the transverse foramen is a unique feature for vertebral arteries and veins travelling to the brain.
* Movement
* Cervical vertebrae allow for; Flexion of the neck (chest to chin), Extension of the neck (looking up to the sky) and rotation (nodding left to right)
* Size
* Smallest of the moveable vertebrae
* Vertebrae increase in size as you go down through the sections
105
Label the general features of the cervical vertebrae
What is the function of the vertebral body?
What is located in the vertebral foramen?
* Vertebral body supports weight
* The vertebral foramen is where the spinal cord is
* Nerves come off the spinal cord therefore as the spinal cord descends, the size of the foramen decreases.
106
What are the names of C1 and C2?
What are their functions?
What type of joint is formed between C1 and C2?
* Atlas (C1): Articular facet of anterior arch
* Axis (C2): Dens (or odontoid process)
* Functions:
* Specialised vertebrae for support, stabilisation and permitting movement of the cranium
* Type of joint
* Pivot joint (synovial) formed by articulations between the atlas and
107
Label the features.
What is the name of this vertebra
108
Label the features.
What is the name of this vertebra
109
What is the name of the joint between the atlas (C1) and occipital bone?
What are three of its features?
What are its functions?
* Name: Atlanto-occipital joint; a craniovertebral joint
* Features
* Condyloid joints (shallow sockets)
* Encased in joint capsule
* Supported by ligaments
* Functions
* The universal joint that permits vertical scanning movement of head (eye/head coordination)
* Flexion and extension
* Saggital plane
* Mediolateral Axis.
* "Specifically feel what is moving when you nod your head "yes"
110
What is the name of the joint between the atlas (C1) and axis (C2)?
What are two of its features?
What are its functions?
* Name: Atlanto-axial joint
* Features:
* 3 articulations: 2x lateral mass + dens + anterior arch
* Supported by the transverse ligament
* Functions: universal joint that permits horizontal scanning movement of head (adapted for eye/head coordination)
* Rotation
* Transverse Plane
* Vertical axis
* "Specifically feel what is moving when you rotate your head no
111
*Case: 16 yr old female suffers head butt from an opposition football player. Clinical depression fracture in her forehead is noted.*
What region/bone is likely to be affected?
What sinuses are likely to be affected?
* Glabella of the frontal bone (in the middle of the superciliary arm), medial to the superciliary arch; ethmoid
* Frontal and ethmoid sinuses
112
*Case: Argument between two men. Attacker swung a spade lodging into victims skull*
What region/bone is likely to be affected?
* Neurocranial fracture
* The latero-posterior attack, fracture of parietal bones (across sagittal suture; extending to lambdoid suture at occipital bone margin.
113
*Case: Gunshot victim; Unkown assailant*
What region/bone is likely to be affected?
* An extensive neurocranial fracture
* Latero-frontal gunshot hole in frontal bone, superior to pterion (frontal, parietal, temporal and greater wing of sphenoid junction)
*
114
*Case: Right hook punch to the left lateral margin of the orbit*
What region/bone is likely to be affected?
* Facial fracture (Orbital blow)
* Superior zygomatic bone suture to frontal bone (zygomaticofrontal suture) and maxilla.
115
Label the skull
* Left side; top to bottom
* Frontal bone
* Parietal bone
* Temporal bone
* Nasal (paired)
* Lacrimal
* Zygomatic
* Maxilla
* Mandible
* Right side; top to bottom
* Sphenoid (posterior wall)
* Ethmoid (ridges, foramen for nerves to smell)
* Inferior nasal conchae
* Vomer (separates two passages)
116
Muscle subdivisions; Axial vs appendicular
How many muscles in the human body?
* Axial muscles (midline head) support and position the axial skeleton
* Head and neck
* Vertebral column
* Oblique and rectus trunk
* Pelvic floor
* Keep us upright
* Not important for movement
* Appendicular muscles support, move and brace the limb
* Protect us from breaking bones
* Approx 700 muscles in the human body
117
Muscle Types: Functional and structural differences
* Strength and range of motion varies based on:
* Number and size of muscle fibres
* I.e. more fibres more contractibility
* Number and size of muscle fibre increases, therefore strength and movement increases
* Arrangement of fibres
* Leveraging (origin and insertion)
* Parallele fibre arrangement
* Long fibres (but less because less acting on an individual tendon)
* Pennate fibre arrangement
* Short fibres (but many for more strength)
* Structure and function of muscle are related
* Therefore axial vs appendicular muscles; different function = different structure.
* Example:
* quadricep; powerful because of its pennate arrangement.
* Sartorius muscle; longest muscle in the human body; parallel arrangement; helps knee move backwards.
118
General details of muscle compartments
* Muscular compartments separated by fascia
* Intermuscular septa
* Sheet of dense connective tissue
* Each compartment
* Functions to move in a specific direction
* Is innervated by a different nervous (variations/branches may occur)
* Is vascularised by different blood supply (variations/branches may occur)
* Clinical consideration
* Compartment syndrome
* Disease/cancer spread
119
Label the transverse section through the midthigh
* Anterior muscle function: lifting the leg
* Anterior compartment
* Receives blood from the same vessel
* Innervated by the same nerve
* Muscles contract together
* Create power when lifting a leg or kicking a ball
* Medial compartment
* Pulls bone towards the midline
* Posterior compartment
* Hamstring
* function: lowering the leg
120
General muscle attachments: Origin vs insertion
* General muscle attachment
* Tendon fibres (collagen-based) fuse and continue into the on the matrix at either end of the muscle belly
* Origin
* Initial attachment site that does NOT move during contraction
* "anchor of muscle"
* Insertion
* Attachment site that muscle contraction aims to move
121
Origin and insertion example: elbow flexion
Which is the origin and which is the insertion site?
* Origin; "beginning of the muscle"
* 1st tendon is fused into the bone
* The muscle belly is attached to the bone on either side
* Insertion
* Pulls on bone towards the origin; lifts arm up.
122
Facial Muscle Attachments: Origin and Insertion
* Origin:
* Initial attachment site that does NOT move during muscle contraction
* Tendon attached to the superficial surface of skull
* Insertion:
* Attachment site that muscle contraction aims to move (insertion site pulls on the skin)
* Epimysium fibers of muscle woven (fused) into subcaneous dermis of skin
123
Muscles of facial expression: Occipitofrontalis
* Has two individual muscle bellies;
* Muscle belly; 'pink/red' component, has all action and myelin filament (contracting component)
1. Occipital Belly (Occipitalis)
* Origin: occipital and temporal bone
* Insertion: epicranial aponeurosis (aponeurosis: Fascia, a sheet of dense CT, does the same thing as a tendon; provides strength and power)
* Action: tense/retracts scalp, assists frontal belly
2. Frontal Belly (Frontalis)
* Origin: epicranial aponeurosis
* Insertion: skin of eyebrow, bridge of the nose
* Action: raise eyebrows (as muscle pulls back), wrinkles forehead
* *IMAGE*
* Blue; epicranial aponeurosis
* Red back part; occipital belly
* red front part: frontal belly
124
Label the 3 red arrows
125
Aponeurosis; Fascia/Dense CT
* Bundles of collagen fibres, delicately layered in thin sheaths
* Replaces the tendon in a flat muscle
* Covers wide area of attachment
* Functions not to move bone (like a tendon) but to spring/provide extra tension
* Abdominal aponeurosis is another example (image)
* image of aponeurosis the top is anterior and bottom is posterior
126
Label this image of the head
127
Muscles of facial expression: eyebrows and eye
1. Corrugator supercilli (muslce that sits on the supercillary arch of the frontal bone
* Origin: the orbital rim of frontal bone near nasal suture (Medial aspect of supercillairy arch)
* Insertion: Towards lateral eyebrow
* Action: pulls eyebrows/skin inferiorly and medical
2. Orbicularis oculi
* Origin: medial margin of orbit
* Insertion: skin around eyelids
* Action: closes/crinkles eye
* Contraction; pulls inwards; reduce circumference around the eye; closes eyelids
3. Levator palpebrae superioris
* Origin: Oribital rim of optic foramen
* Insertion: eyelid
* Action: elevates upper eyelid
128
What is this muscle?
129
Name this bony ridge?
130
True or false: The inferior levator palpebrae is located on the face?
* False
* There is no inferior levator palpebrae
131
What muscle is this?
Which site (purple and yellow) is the origin and which is the insertion?
* Muscle: Levator palpebrae superioris
* Purple end: insertion into eyelid
* yellow end: origin site
132
Muscles of facial expression: the nose
1. Nasalis
* Origin: Maxilla and Alar Cartilage (soft cartilage; gives nose shape)
* Insertion: Bridge of nose
* Action: Compresses bridge, depresses tip and elevates flares nostrils
133
Name the muscle
134
Muscles of facial expression: the mouth (part 1)
1. Obicularis Oris
* Origin: Maxilla and mandible
* Insertion: Lips
* Action: Compresses lips
135
What muscle is this?
136
Orbicularis oris vs obbicularis oculi
* Oculi = eye
* Oris = oral/mouth
137
Muscles for Facial expression: the mouth part 2 (smiling)
2. Levator Labii Superioris (*levator =* "elevate/lift" *labil* = "lip" *superiroris* = "superially")
* Origin: Inferior orbit margin (superior to infra-orbital foramen)
* Insertion: Orbicularis oris
* Action: Elevates upper lip
3. Levator Anguli Oris (*anguli*
* Origin: Maxilla (inferior to infra-orbital foramen)
* Insertion: Corner of mouth
* Action: Elevates corners of mouth
4. Zygomaticus Minor
* Origin: Zygomatic bone, lateral infaorbital margin
* Insertion: Upper lip
* Action: Retracts and elevates upper lip
5. Zygomaticus Major
* Origin: Zygomatic bone near suture to maxilla
* Insertion: Angle of mouth
* Action: Elevates & retracts corners of mouth
6. Risorius
* Origin: Fascia surrounding parotid salivary gland
* Insertion: Angle of mouth
* Action: Draws corner of mouth to the side
138
Name the 3 bones in the image
139
Muscles of facial expression: the mouth part 3 (frowning)
Name the muscles
7. Mentalis (*sits on the mandible)*
* Origin: Incisive fossa of mandible
* Insertion: Skin of chin
* Action: Elevates and protrudes lip
8. Depressor anguli oris (*depressor =* "bring down" *angulis* = "angle of the mouth")
* Origin: Anterolateral surface of the mandible
* Insertion: Skin at mouth angle
* Action: depresses mouth corners
9. Depressor labii inferioris
* Origin: Mandible anterior midline
* Insertion: Skin of lower lip
* Action: Depresses lower lip
140
Muscles of facial expression: the neck
name the red arrow label
1. Platysma (*a sheet like muscle)*
* Origin: Superior thorax (between cartilage of 2nd rib and acromion of scapula)
* Insertion: Skin of cheek & mandible ridge
* Action: Tenses skin of neck; depresses mandible, pulls lower lip inferiorly
141
Muscles of mastication: muscles that move the "JAW"
label muscles
1. Temporalis
* Origin: Temporal line & Temporal bone
* Insertion: Coronoid process of mandible
* Action: Elevates mandible
2. Masseter
* Origin: Zygomatic arch •
* Insertion: Lateral surface of mandible ramus
* Action: Elevates mandible & closes jaw
142
Muscles of mastication: muscles that move the "JAW"
Label muscles
* The Pterygoids: Located deep to mandible
* Origin: Both Pterygoids (medial and lateral) originate at the Pterygoid plate; infratemporal surface
* Medial Pterygoid:
* Inserts: Medial surface of mandible angle (body and ramus)
* Action: Elevates mandible (closes mouth)
* Lateral Pterygoid:
* Inserts: Articular disc in TMJ (*temporal mandibular joint; betw/ temple and madible)*; Mandibular condyle
* Action: Lowers mandible (opens mouth)
## Footnote
*drawn black arrow indicates the direction of contraction*
143
Muscles of mastication
What muscle is this?
Is it opening or closing the jaw?
* Lateral pterygoid = "opens jaw"
* Inserts into the condular head
* contracts = bring condular head towards the origin site = jaw opens
144
Muscles of mastication
What muscle is this?
Is it opening or closing the jaw?
* Medial pterygoid: closes jaw
* positioned in a superior to inferior direction; contracts upwards to origin site, closing the jaw
145
Muscles of the neck: anterior compartment
1. Sternocleidomastoid (SCD)
* Origin:
* Sternal head attaches to sternum
* Clavicular head attaches to clavicle
* Insertion: Mastoid region of temporal bone
* Actions:
* Lateral flexion of head (both heads - unilateral)
* Contralateral head rotation (sternal head - unilateral)
* Head elevation (both heads – bilateral) (not looking up though)
146
Vasculature of the neck; arterial
label the four arteries
1. Common carotid
* Divides into the internal and external carotid artery
* internal: enters the skull through the carotid canal of temporal bones
* External branches to supply neck, jaw and cranium
2. Vertebral artery
* Ascends within transverse foramina of cervical vertebrae
* Enters cranium to hindbrain
147
Label the vasculature of the neck
148
Vasculature of the neck; venous
label the diagram
1. External Jugular vein
* Receives blood from surface of cranium, face & jaw
* Drains into brachiocephalic vein
2. Internal Jugular vein
* Receives blood from internal cranium, brain face & neck
* Exits skull through jugular foramen into brachiocephalic vein
* Common = is one and then splits
149
Label the venous vasculature of the neck
150
