Human Anatomy & Physiology
Week 4: Skin
Jonathon Odom MS
Levels of Organization
2
Learning Objectives
Understand the key components of the epidermal layers and which regions they are associated with
Understand what makes fingerprints
Understand the difference in skin color and the contributing factors
Understand key components of the dermis
Understand key components of hypodermis
Understand hair distribution and anatomy
Understand what is produced by each type of sweat gland
Be familiar with the components of nails
Functions of the Integumentary System
Functions include
Protection
Excretion
Temperature regulation
Nutrient storage
Vitamin D3 synthesis
Sensory detection
Components of the Integumentary System
Cutaneous membrane
Epidermis
Dermis
Subcutaneous layer (also called superficial fascia or hypodermis)
Accessory structures
Hair
Nails
Glands
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Functions of Epidermis
Provides mechanical protection
Prevents fluid loss water resistant
Keeps microorganisms from invading the body
Gives each person unique skin color
Integument Organization and Structure
The skin can be divided into two main components, a thin superficial layer called the epidermis and a deeper thicker layer called the dermis. Each can be further divided into layers and structural components
Layers of the Epidermis (superficial to deep):
Stratum corneum
Stratum lucidum (found only in thick epidermis)
Stratum granulosum
Stratum spinosum
Stratum germinativum (basale)
Contains stem cells that replenish cells as
superficial layers slough off
http://www.physioweb.org/IMAGES/epidermis_mag.jpg
Remembering the order of the layers: Can Lucy Get Some Gum?
-Tell them to pay attention to superficial and deep! On the quiz, we may ask them to list the layers deep to superficial OR superficial to deep, so they should be prepared to list them either way.
-spinosum is keratin added to cells
Layers of the Epidermis
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Thin vs Thick Skin
Thin (epidermis = 0.08 mm)
4 layers
Most of the body
Lips, scrotum & penis, eyelids exceptionally thin
Thick (epidermis = 0.5 mm)
5 layers
Palms of hands, soles of feet
Stratum corneum
Stratum granulosum
Stratum spinosum
Stratum germinativum (basale)
Stratum corneum
Stratum lucidum (found only in thick epidermis)
Stratum granulosum
Stratum spinosum
Stratum germinativum (basale)
Real-Quick-Review
Multiple Choice
1. The stratum of epidermis found only in thick skin is the:
A) Stratum corneum
B) Stratum lucidum
C) Stratum granulosum
D) Stratum spinosum
E) Stratum germinativum
2. This stratum of epidermis contains stem cells that replenish cells as superficial layers slough off
A) Stratum corneum
B) Stratum lucidum
C) Stratum granulosum
D) Stratum spinosum
E) Stratum germinativum
B, Lucidum
E, Germinativum
Fingerprints
The epidermis is firmly attached to underlying dermis via egg-carton-like structures formed by
The epidermal ridges on the epidermis
The dermal papillae on the dermis
Fingerprints
The epidermis is secured to the dermis through a series of epidermal ridges and dermal papillae that act as a lock
Such structures are more prevalent in areas with high frictional stress such as the sole of the feet
Excessive friction may cause the two layers to separate, filling the space with interstitial fluid thus creating a blister
Epidermal ridges that extend into the stratum corneum are known as fingerprints and found in areas of extreme friction
Biological Function: increased grip
Skin Color
The base layer of the epidermis is the stratum germinativum. This layer contains special cells called melanocytes that dictate the color of our skin
Melanocytes produce melanin which absorbs UV radiation
Pale ivory skin=low melanocyte activity
Dark ebony= high melanocyte activity
For those who have low melanocyte activity, skin color is determined by two other factors:
Carotene: orange pigment
Dermal blood supply: rosy appearance
Melanocytes
Dark skin is the result of increased melanocyte activity not melanocyte number // the cells are just more active & produce more melanin
Pathologic Skin Color
Cyanosis: blue color, blue-lips, blue-fingertips, due to lack of blood supply
Jaundice: increased bilirubin, yellow skin appearance
Real-Quick-Review
Fill-In-The-Blank
1. Melanocytes produce _________, which absorbs UV radiation
2. The orange pigment in skin is called _________
3. What is responsible for the rosy appearance skin can take on?
4. The 2 types of extracellular fibers in skin which provide strength and stretch are called
_________ and _________
Melanin
Carotene
Dermal blood supply
Collagen and Elastin
Epidermal Physiology
Protection:
Melanin protects against excessive or intense UV radiation
Keratin Keratinize the skin cells for protection
Nutrients:
Vitamin D3 (cholecalciferol) Synthesized from UV radiation (sunlight)
Replacement:
Epidermal cells respond to epidermal growth factor (EGF)
Repair injury
Growth/differentiation
Secretions from glands
Components of the Integumentary System
Cutaneous membrane
Epidermis
Dermis
Subcutaneous layer (also called superficial fascia or hypodermis)
Accessory structures
Hair
Nails
Glands
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Dermal Organization
Divided into two layers
Papillary layer
Areolar tissue
Contains blood and lymph vessels, lymph nodes and sensory nerves of epidermis
Reticular layer
Dense Irregular CT
Contains network of collagen and elastic fibers to resist tension
Dermis Organization and Structure
The dermis lies below the epidermis and contains many structures such as blood vessels, nerves, sensory receptors, extracellular fibers, hair follicles, and glands
Blood Vessels (arteries and veins) are divided by location:
Superficial
Deep
Lymph
Nerves interpret information from specialized sensory receptors:
Extracellular fibers
Collagen: strength
Elastin: stretch
http://classconnection.s3.amazonaws.com/49/flashcards/491049/jpg/f450061362111508057.jpg
For nervessometimes coming up with weird ways to remember their names helps (ie. if mice were running across your skin, your Meissners corpuscles would detect it; pacific ocean is really heavy, etc 😉
Dermal Innervation
Nerve Distribution & Function
Superficial
Free nerve ending- pain, temperature
Meissners corpuscles: light pressure
Merkel cells: soft touch or stroke
Deep:
Pacinian corpuscles: heavy pressure
Free nerve ending on hair follicle-motor control
Skin Elasticity
Elastin fibers allow the skin to stretch and then return to original shape & location
Collagen fibers (normally) prevent the skin from stretching too far
Elastin, Collagen and Water maintain skin properties called skin turgor
Dehydration causes a loss of skin turgor
Diagnosed by the pinch test
Stretching the skin beyond its limits causes damage called stretch marks
Components of the Integumentary System
Cutaneous membrane
Epidermis
Dermis
Subcutaneous layer (also called superficial fascia or hypodermis)
Accessory structures
Hair
Nails
Glands
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The Hypodermis
The hypodermis is a connective tissue and not considered part of the integument though it lays adjacent to the dermis (hypo=below).
Content and distribution of areolar and adipose tissue, gives shapes the body giving each person a somewhat unique superficial appearance.
In comparison to the epidermis and dermis, the hypodermis is typically quite thick depending on the bodily location.
Superficial layers: high blood supply
Deep layers: low blood supply
Clinical Correlation: SubQ injection would be deep to this tissue
http://www.dartmouth.edu/~anatomy/Histo/lab_4/skin/DMS033/01.gif
Components of the Integumentary System
Cutaneous membrane
Epidermis
Dermis
Subcutaneous layer (also called superficial fascia or hypodermis)
Accessory structures
Hair
Nails
Glands
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Anatomy of Hair
Structure and Function
Arrector pili muscle: nervous stimulation lifts the shaft, increasing skin sensitivity
Papilla: vascular structure that provides nutrients
Matrix: location of new hair growth
Sebaceous gland: coat hair with oily protectant
Shaft Layers (superficial to deep)
Cuticle-soft exterior made of dead cells
Cortex-hard interior for support
Medulla-middle most structure, center of hair shaft
Types of Hair
Vellus hairs (short & thin)
covers most of the body (vellus, think all over us)
Terminal hairs (long & thick)
head, eyebrows, eyelashes
pubic hair is a special terminal hair thats generally thicker & more curly
Club hair (cessation of growth)
Forms when a hair stops growing
Shed and replaced with new hair according to hair growth cycle
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Types of Hair
Vellus hairs (short & thin)
covers most of the body (vellus, think all over us)
Terminal hairs (long & thick)
head, eyebrows, eyelashes
pubic hair is a special terminal hair thats generally thicker & more curly
Club hair (cessation of growth)
Forms when a hair stops growing
Shed and replaced with new hair according to hair growth cycle
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Nails
Nails function to strengthen the distal portion of digits.
Structure and Function
Nail Matrix: mitotically active zone of nail growth
Lunula: newly formed and undifferentiated white cells of nail body
Eponychium: epidermal cells dragged forward along the body as the nail grows, otherwise known as the cuticle
Hyponychium: epidermal cells dragged beneath the body as the nail grows
Free edge of nail extends over hyponychium
http://www.lrn.org/Popup/Skin/figure4_4.html
They need to know 5-9 in their lab manual, which is similar to this image
Glands
Secretory glands are located in the dermis and empty onto the surface of the skin. There are four types found on the human body:
Sudoriferous Glands: produces watery secretion called sweat
Eccrine: found abundantly across the body and excrete mostly water
Apocrine: found in the armpits, groin, and surrounding the nipples, this gland produces a more concentrated secretion
Sebaceous Glands: produces oily secretion called sebum
Typically associated with hair follicles
Ceruminous Glands: produce waxy secretion called cerumen
Found exclusively in the ear
Mammary Glands: produce milk
Found in the breast but only active in pregnant and nursing women
Secretions function to cool, lubricate, and protect the skin.
They need to know the main types of glands and the subtypes and what they produce (so basically this whole slide)
Real-Quick-Review
Fill-In-The-Blank
1. Hair and nails are composed of a protein called _____________
2. Long, thick hair is called _________ hair; while short, thin hair is called __________ hair
3. The deepest shaft layer of hair is called the ___________
4. The newly formed and undifferentiated white cells of a nail body are called the _________
5. What type of gland produces the waxy secretion, called cerumen, found exclusively in the ear?
Keratin
Terminal, Vellus
Medulla
Lunula
Ceruminous Skeletal System
Professor Odom
Levels of Organization
2
Learning Objectives
List and describe the functions of bones
Describe the classes of bones
Discuss the process of bone formation and development
Discuss the effect of exercise, nutrition, and hormones on bone tissue
Describe how an imbalance of calcium can affect bone tissue
Explain how bone repairs itself after a fracture
Functions of Skeletal System
Supports the body
Provides attachment for muscles to facilitate movement
Protects internal organs and structures
RBC production
Mineral storage
Learning Objectives
List and describe the functions of bones
Describe the classes of bones
Discuss the process of bone formation and development
Discuss the effect of exercise, nutrition, and hormones on bone tissue
Describe how an imbalance of calcium can affect bone tissue
Explain how bone repairs itself after a fracture
Bone Classifications
There are 206 bones in an adult human skeleton
Axial (80) vs. Appendicular (126)
Classifications:
Flat
Long
Short
In terms of shaft length
Sesamoid
Like a seed
Irregular
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Bone Classifications
Bone Classifications
Bone classification Features Function(s) Examples
Long Cylinder-like shape, longer than it is wide Leverage Femur, tibia, fibula, metatarsals, humerus, ulna, radius, metacarpals, phalanges
Short Cube-like shape, approximately equal in length, width, and thickness Provide stability, support, while allowing for some motion Carpals, tarsals
Flat Thin and curved Points of attachment for muscles; protectors of internal organs Sternum, ribs, scapulae, cranial bones
Irregular Complex shape Protect internal organs Vertebrae, facial bones
Sesamoid Small and round; embedded in tendons Protect tendons from compressive forces Patellae
Learning Objectives
List and describe the functions of bones
Describe the classes of bones
Discuss the process of bone formation and development
Discuss the effect of exercise, nutrition, and hormones on bone tissue
Describe how an imbalance of calcium can affect bone tissue
Explain how bone repairs itself after a fracture
Anatomy of Bone
Epiphysis: end of long bone
Proximal
Distal
Diaphysis: Shaft
Metaphysis: Narrow portion between diaphysis and epiphysis, contains growth plate
Periosteum: outer layer (peri=around, osteum=bone)
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Bone Growth
Growth occurs between the diaphysis and the epiphysis in the epiphyseal plate
Epiphyseal plate contains cartilage until growth is complete
Cartilage growth occurs on distal end of plate while bone is added medially
Diaphysis lengthens
When growth is complete, the plate becomes the epiphyseal line
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Bone External Structure / Markings
Bone Markings
Marking Description Example
Articulations Where two bones meet Knee joint
Head Prominent rounded surface Head of femur
Facet Flat surface Vertebrae
Condyle Rounded surface Occipital condyles
Projections Raised markings Spinous process of the vertebrae
Protuberance Protruding Chin
Process Prominence feature Transverse process of vertebra
Spine Sharp process Ischial spine
Tubercle Small, rounded process Tubercle of humerus
Tuberosity Rough surface Deltoid tuberosity
Line Slight, elongated ridge Temporal lines of the parietal bones
Crest Ridge Iliac crest
Holes Holes and depressions Foramen (holes through which blood vessels can pass through)
Fossa Elongated basin Mandibular fossa
Fovea Small pit Fovea capitis on the head of the femur
Sulcus Groove Sigmoid sulcus of the temporal bones
Canal Passage in bone Auditory canal
Fissure Slit through bone Auricular fissure
Foramen Hole through bone Foramen magnum in the occipital bone
Meatus Opening into canal External auditory meatus
Sinus Air-filled space in bone Nasal sinus
Bone Structure: Internal
Internal Structure
Compact (load bearing): densely packed hydroxyapatite
Contains Yellow marrow
Spongy: trabeculae
Better manage stress from multiple directions
Contains Red Marrow
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Bone Structure: Internal
Bone Cavities
Red marrow: site of RBC production
Yellow marrow: filled with adipose
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Bone Structure: Internal
Internal Structure
Compact (load bearing): densely packed hydroxyapatite
Contains Yellow marrow
Spongy: trabeculae
Better manage stress from multiple directions
Contains Red Marrow
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Compact Bone
Organized in Osteons (Haversian System)
Bone (Osseus) Tissues
Osteon (Haversian System): basic structural unit
Central canal/Haversian Canal: contains nerves and vasculature
Concentric lamellae
Pockets in concentric lamellae are lacuna and contain osteocytes
Lacuna are connected to central canal via canaliculi
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Bone Structure: Internal
Internal Structure
Compact (load bearing): densely packed hydroxyapatite
Contains Yellow marrow
Spongy: trabeculae
Better manage stress from multiple directions
Contains Red Marrow
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Spongy Bone
Also contains:
Organized in Osteons (Haversian System)
But in a Trabecular network
Other Important Bone Cells
Important Bone Cells
Bone Cells
Cell type Function Location
Osteogenic cells Develop into osteoblasts Deep layers of the periosteum and the marrow
Osteoblasts Bone formation Growing portions of bone, including periosteum and endosteum
Osteocytes Maintain mineral concentration of matrix Entrapped in matrix
Osteoclasts Bone resorption Bone surfaces and at sites of old, injured, or unneeded bone
Now that weve discussed
some of the
Important Cells related to Bone lets revisit growth!
Ossification
Ossification is the transition from cartilage to bone (simplified definition)
Types of Ossification:
Intramembranous ossification
Endochondral ossification
Intramembranous Ossification
Intramembranous ossification: compact and spongy bone develops directly from sheets of mesenchymal (undifferentiated) connective tissue.
Where (Examples): flat bones of skull, mandible and clavicle
Remember this??
Connective Tissue Proper: Loose
Loose Connective Tissue
The packing material of the body
Fills empty spaces
Cushion & stabilize organs; support epithelia, blood vessels and nerves
Types include
Areolar tissue
Adipose tissue
Reticular tissue
Mesenchyme & Mucous tissue (embryos only)
Adipose
Reticular
Areolar
Connective Tissue Proper:
Loose
Areolar
Adipose
Reticular
Mesenchyme
Dense
Regular
Irregular
Elastic
Fluid
Blood
Lymph
Solid
Bone
Cartilage
Hyaline
Elastic
Fibrocartilage
Produced by the Mesoderm in embryo
Provides multiple uses during development
Intramembranous Ossification
Intramembranous ossification: compact and spongy bone develops directly from sheets of mesenchymal (undifferentiated) connective tissue.
Where (Examples): flat bones of skull, mandible and clavicle
How:
Mesenchymal cells
Osteoblasts
Cluster together to form a ossification center
Secrete Osteoid (uncalcified matrix)
Calcifies (hardens) as calcium phosphate is deposited around osteoblasts
Osteoblasts Osteoclasts
Ossification
Ossification is the transition from cartilage to bone (simplified definition)
Types of Ossification:
Intramembranous ossification
Endochondral ossification
Skeleton Cartilage
Hyaline Cartilage:
Most abundant
Covers articulating surfaces (joints)
Flexible
Fibrocartilage:
Stiff and tough; absorbs force
Found in intervertebral discs and meniscus
Elastic Cartilage:
Least abundant
Most flexible
Found in ear and epiglottis
Review Slide
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Endochondral Ossification
Endochondral ossification, bone develops byreplacinghyaline cartilage. Cartilage does not become bone. Instead, cartilage serves as a template to be completely replaced by new bone. Endochondral ossification takes much longer than intramembranous ossification.
Where: all bones except flat bones of skull, mandible and clavicle
How (long bone):
Week 6-8 of embryonic development Mesenchymal cells
Chondrocytes precursor of bones (a)
Perichondrium (a membrane that covers the cartilage) appears(b)
Uncalcified matrix grows
Chondrocytes also grow in size
Matrix begins to calcify
Endochondral Ossification
Endochondral ossification, bone develops byreplacinghyaline cartilage. Cartilage does not become bone. Instead, cartilage serves as a template to be completely replaced by new bone. Endochondral ossification takes much longer than intramembranous ossification.
Where: all bones except flat bones of skull, mandible and clavicle
How (long bone):
Matrix begins to calcify
Prevents chondrocytes from receiving nutrients
Chondrocyte death and disappear
Blood vessels invade spaces
Enlarges cavity (eventually becomes medullary cavity)
Initiates the transformation of the perichondrium into the bone-producing periosteum
and brings osteogenic cells
Osteoblasts begin to form
Endochondral Ossification
Endochondral ossification, bone develops byreplacinghyaline cartilage. Cartilage does not become bone. Instead, cartilage serves as a template to be completely replaced by new bone. Endochondral ossification takes much longer than intramembranous ossification.
Where: all bones except flat bones of skull, mandible and clavicle
How (long bone):
Osteoblasts begin to form
A periosteal collar of compact bone around the cartilage of the diaphysis
2nd-3rd month of embryonic developmentprimary ossification center forms, a region deep in the periosteal collar where ossification begins (c)
This process continues.
Chondrocytes continue to grow proximally and distally forming the epiphyses and consist of the epiphyseal plate, while osteocytes continue to replace chondrocytes in the diaphysis
Eventually this process occurs in the epiphyseal regions and is referred to as secondary ossification (e)
Coolwe still havent answered the question.
How do we grow?
Bone Growth
Growth occurs between the diaphysis and the epiphysis in the epiphyseal plate
Epiphyseal plate contains cartilage until growth is complete
Cartilage growth occurs on distal end of plate while bone is added medially
Diaphysis lengthens
When growth is complete, the plate becomes the epiphyseal line
Review Slide
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Bone Growth in Length
The epiphyseal plate is composed of four zones of cells and activity:
Reserve zone
Proliferative zone
Zone of maturation and hypertrophy
Zone of calcified matrix.
Bone Growth in Diameter
This is called appositional growth. Is controlled by the balance of osteoclasts vs osteoblasts which are stimulated by aging and compressive forces as well as hormones
Osteoclasts resorb old bone that lines the medullary cavity
Osteoblasts produce new bone tissue beneath the periosteum.
The erosion of old bone along the medullary cavity and the deposition of new bone beneath the periosteum not only increase the diameter of the diaphysis but also increase the diameter of the medullary cavity. This process is calledmodeling.
Learning Objectives
List and describe the functions of bones
Describe the classes of bones
Discuss the process of bone formation and development
Discuss the effect of exercise, nutrition, and hormones on bone tissue
Describe how an imbalance of calcium can affect bone tissue
Explain how bone repairs itself after a fracture
Exercise and Mechanical Stress
Mechanical stress stimulates the deposition of mineral salts and collagen fibers.
The internal and external structure of a bone will change as stress increases or decreases so that the bone is an ideal size and weight for the amount of activity it endures.
That is why people who exercise regularly have thicker bones than people who are more sedentary. The bones undergo remodeling as a result of forces (or lack of forces) placed on them.
Resistance training is especially important to slow down the eventual bone loss due to aging and for preventing osteoporosis.
Hormones that affect Bone Growth
Hormones that have a (+) affect on growth:
GH: increases length and mineralization
Thyroxine: stimulates bone growth
Sex Hormones (E2, T): stimulate growth and osteoblasts
Calcitonin: increases kidney excretion of calcium and inhibits osteoclasts
Calcitriol: stimulates osteoclastic activity and increases absorption of calcium in the gut
Hormones that have a (-) affect on growth:
PTH: stimulates osteoclasts and reabsorption of calcium in the kidney
Calcium and Vitamin D
Bone is made of: Calcium phosphate and calcium carbonate
Calcium needs Vitamin D to be absorbed form the intestines
Sources of Calcium: milk, green leafy vegetables, broccoli, and intact salmon and canned sardines with their soft bones. Nuts, beans, seeds, and shellfish provide calcium in smaller quantities.
Sources of Vitamin D: most commonly acquired from sunlight, supplements and fortified milk.
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2
Solid Supporting Connective Tissue
Cartilage & Bone
Provide a strong framework of support & protection for the body as well as mineral sources
Bone-solid component for attachment, protection, minerals, & RBC production
Organic component: collagen
Inorganic component: calcium phosphate in chemical arrangement called calcium hydroxyapatite
Cartilage-articular surface of joints
Hyaline
Elastic
Fibrocartilage
Review Slide
Learning Objectives
List and describe the functions of bones
Describe the classes of bones
Discuss the process of bone formation and development
Discuss the effect of exercise, nutrition, and hormones on bone tissue
Describe how an imbalance of calcium can affect bone tissue
Explain how bone repairs itself after a fracture
Homeostatic Control of Calcium
Thyroid Gland
Parafollicular cells produce Calcitonin (CT)
Cells monitor concentration of calcium in blood & release calcitonin when blood calcium is too high
Kidneys respond to CT by excreting calcium into urine, reducing blood levels
Tone down Ca2+
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Parathyroid Glands
4 small nodules on the posterior surface of the thyroid gland
Produce PTH (parathyroid hormone)
Released when blood calcium is too low
Kidneys respond by keeping calcium in the blood, and by releasing calcitriol aka vitamin D synthesis
Causing GI to increase absorption
Stimulates osteoclasts that dissolve bone to add calcium to the blood
Homeostatic Control of Calcium
Learning Objectives
List and describe the functions of bones
Describe the classes of bones
Discuss the process of bone formation and development
Discuss the effect of exercise, nutrition, and hormones on bone tissue
Describe how an imbalance of calcium can affect bone tissue
Explain how bone repairs itself after a fracture
Fractured Bone Definitions
Afractureis a broken bone.
Closed reduction is when a broken bone is manipulated and set into its natural position without surgery
Open reductionrequires surgery to expose the fracture and reset the bone.
It will heal whether or not a physician resets it in its anatomical position. If the bone is not reset correctly, the healing process will keep the bone in its deformed position.
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Fractured Bone Definitions
Closed: skin remains in tact
Open: one end has penetrated through skin (high infection risk)
Transverse: Occurs in transverse plane, straight across
Spiral: Bones are split as result of twisting motion
Communicated: several breaks with small pieces in between each segment
Impacted: compression that has driven one segment into the other
Greenstick: only one side of bone is broken
Oblique: occurs at a angle that is not 90 degrees
It will heal whether or not a physician resets it in its anatomical position. If the bone is not reset correctly, the healing process will keep the bone in its deformed position.
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Fractured Bones
Types of Fractures
Type of fracture Description
Transverse Occurs straight across the long axis of the bone
Oblique Occurs at an angle that is not 90 degrees
Spiral Bone segments are pulled apart as a result of a twisting motion
Comminuted Several breaks result in many small pieces between two large segments
Impacted One fragment is driven into the other, usually as a result of compression
Greenstick A partial fracture in which only one side of the bone is broken
Open (or compound) A fracture in which at least one end of the broken bone tears through the skin; carries a high risk of infection
Closed (or simple) A fracture in which the skin remains intact
Bone Healing
Hematoma
Internal Callus of fibrocartilage
External Callus of hyaline cartilage
Osteoclasts destroy dead osteocytes, osteoblasts create new osseous tissue and cartilage is replaced
50 Professor Odom
Levels of Organization
2
Learning Objectives
Describe and Understand the Axial and Appendicular Skeleton
Identify the bones and bony structures of the skull, the cranial suture lines, the cranial fossae, and the openings in the skull
Discuss the vertebral column and regional variations in its bony components and curvatures
Be able to compare and contrast each segment of vertebrae
Describe the components of the thoracic cage
Identify key features for each axial and appendicular bones
Identify the features of the pelvis and explain how these differ between the adult male and female pelvis
Axial Skeleton: Overview
80 bones in the axial skeleton
Cephalic
Cranial (8)
Facial (14)
Auditory Ossicles (6)
Hyoid (1)
Thoracic Cage
Ribs (24)
True Ribs (14 total)
False Ribs (6 total)
Floating (4 total)
Sternum (1)
Vertebral Column
Vertebrae
Cervical (7)
Thoracic (12)
Lumbar (5)
Sacrum (1)
Coccyx (1)
This is more for overview, they dont need to know the specific numbers for everything, EXCEPT true false and floating ribs
True-1-7
False-8-10
Float-11,12
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Real-Quick-Review
True or False
1. Bone growth occurs between the diaphysis and the epiphysis in the epiphyseal line
2. When growth is complete, the epiphyseal plate becomes the epiphyseal line
3. Hyaline cartilage is the least abundant throughout the body
4. The ribs would be classified as axial skeleton
False, plate
True
False, most abundant
True
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Axial Skeleton: Cephalic: Cranial
Frontal
Sphenoid
Ethmoid
Temporal
Parietal
Occipital
Know and be able to identify each of these bones
KNOW THESE REALLY WELL
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Axial Skeleton: Cephalic: Facial
Palantine
Know and be able to identify each of these bones
KNOW THESE REALLY WELL
The bones of the skull are the only things from these two slides that theyll need to know for their quiz, but they WILL need to know foramina and other bone markings for their practical. A study guide will be posted next weekend with details regarding which bones/bone markings they need to know for the practical.
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Foramen of Skull
Foramen of Sphenoid Bone
Axial Skeleton: Hyoid
Floats at the level of cervical vertebrae 3
Does not articulate other bones
Attached by ligaments from styloid and hangs like a swing
Serves as attachment site for other muscles
Cornu=horn
It exists
Theres not a whole lot they need to know about the hyoidreally just the three things in red.
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Axial Skeleton: Vertebral Column
Anatomical Shape
Concave
Concave
Convex
Convex
Axial Skeleton: Vertebral Column
Pathologic Shape
Scoliosis: Abnormal lateral curvature
Kyphosis: exaggerated thoracic curvature
Lordosis: exaggerated lumbar curvature
Mention pathologies associated with spinal columnkyphosis, lordosis, scoliosis
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Anatomy of Individual Vertebrae
Vertebral Body
Vertebral Arch
Pedicle – (pillars)
Lamina – (arch)
Vertebral Foramen (opening/hole)
Spinous process (Process = projection)
Transverse processes
Anatomy of Individual Vertebrae
Vertebral Body
Vertebral Arch
Pedicle – (pillars)
Lamina – (arch)
Vertebral Foramen (opening/hole)
Spinous process (Process = projection)
Transverse processes
Axial Skeleton: Vertebrae:
C1-C7 vertebrae
C1=atlas
C2=axis
Dens
C7=vertebral prominens
Identifying Characteristics
Large vertebral foramina
Transverse Foramen
Bifid spinous process
Vertical angle
Small body
Transverse Foramen
Bifid Spinous Process
Cervical
Elephant
They need to know C1 and C2 as well as their common names, Atlas and Axis
They need to know it is C7 they can easily palpate on themselves and others
Spend some time on the different types of vertebra, theyll need to know how to identify each kind
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Axial Skeleton: Vertebrae:
T1-T12
Identifying Characteristics
Medium size body
Costal facets that articulate with ribs
Vertically angled spinous process
Thoracic
Giraffe
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Axial Skeleton: Vertebrae:
L1-L5
Identifying Characteristics
Large bodies
Small vertebral foramina
More horizontal spinous process
Triangular vertebral foramen
Lumbar
Giraffe
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Difference between Vertebrae
Difference between Vertebrae
Axial Skeleton: Vertebrae:
Sacrum is 5 fused vertebrae
S1 S5
Base of Sacrum
Median Sacral Crest
Superior Articular Facet
Sacrum
Giraffe
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Axial Skeleton: Vertebrae:
Coccyx aka tailbone
Consists of 3-5 fused vertebrae
Anchors spinal cord
Coccyx
Giraffe
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Intervertebral Discs
intervertebral discis a fibrocartilaginous pad that fills the gap between adjacent vertebral bodies
anulus fibrosusis the tough, fibrous outer layer of the disc. It forms a circle (anulus = ring or circle) and is firmly anchored to the outer margins of the adjacent vertebral bodies. Inside is the
nucleus pulposus, consisting of a softer, more gel-like material. It has a high water content that serves to resist compression and thus is important for weight bearing.
Herniated Disc
Herniation can ha