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== The Integumentary System - What is it? ==
== The Integumentary System  ==
 
[[File:Skin blank.jpg|right|frameless]]
[[Image:EpidermalLayersHistology.png|thumb|right|200x350px|Layers of the Skin]] Pronounced&nbsp;in•teg•u•men•ta•ry, this system is colloquially known as the skin and is an organ system which has many functions. This article will hopefully explain the different anatomical layers and physiological functions of the skin and also demonstrate why it is important to have an understanding of the skin with relation to clinical physiotherapy practice.<br>
The integumentary system is the largest organ of the body that forms a physical barrier between the external environment and the internal environment that it serves to protect and maintain.  
 
== An Introduction - Key Facts  ==
 
#Skin accounts for about 16% of your total body weight&nbsp;<ref name="One" />
#Its surface area covers between 1.5-2m<sup>2&nbsp;</sup><ref name="One" />
#Weighs approximately 3-5kg&nbsp;<ref name="Two">Turkington C, Dover JS. Skin Deep. 3rd ed. New York: Checkmark Books. 2007</ref>
#Is generally 1-2mm thick, but varies depending on its function, 0.5mm on eyelids but 3.4mm on soles of your feet&nbsp;<ref name="p3">Tortora GJ, Derrickson BH. Principles of Anatomy and Physiology: Organisation, Support and Movement and Control Systems of the Human Body. Volume 1. 12th ed. Hoboken: John Wiley and Sons. 2009</ref>
#It is your body's first line of defence&nbsp;<ref name="One" />
#The system contains all of the appendages including hair, nails, sebaceous glands and sweat glands<ref name="p4">National Library of Medicine. Medical Subject Headings (MESH) http://www.nlm.nih.gov/cgi/mesh/2011/MB_cgi?modeterm=Integumentary+System (accessed 11 June 2013)</ref>
#Skin is made up of the Epidermis and the Dermis, each having separate sublayers&nbsp;<ref name="p5">Mclafferty E Hendry C Farley A. The integumentary system: anatomy, physiology and function of skin. Nursing Standard 2010;27:35-42.</ref>
 
<br>


The integumentary system includes
* [[Skin]] (epidermis, dermis)
* Hypodermis
* Associated [[Metabolic and Endocrine Disorders|glands]]
* Hair
* Nails.
In addition to its barrier function, this system performs many intricate functions such as body temperature regulation, cell fluid maintenance, synthesis of [[Vitamin D Deficiency|Vitamin D]], and detection of stimuli. The various components of this system work in conjunction to carry out these functions<ref name=":0">Kim JY, Dao H. [https://www.ncbi.nlm.nih.gov/books/NBK554386/ Physiology, Integument]. InStatPearls [Internet] 2020 Feb 17. StatPearls Publishing.Available from:https://www.ncbi.nlm.nih.gov/books/NBK554386/ (last accessed 23.10.2020)</ref>.
== General Function  ==
== General Function  ==
The integumentary system has several functions that provide several purposes<ref name="one">Martini FH, Nath, JL. Fundamentals of Anatomy and Physiology. 8th ed. Pearson. San Francisco: Benjamin Cummings. 2009</ref>: [[File:Wound botulism.jpg|right|frameless]]


The skin has several functions that provide several purposes<ref name="one">Martini FH, Nath, JL. Fundamentals of Anatomy and Physiology. 8th ed. Pearson. San Francisco: Benjamin Cummings. 2009</ref>&nbsp;;
* Physical protection: The integumentary is the covering of the human body and its' most apparent function is physical protection: skin - a tightly knit network of cells, with each layer contributing to its strength. The epidermis has an outermost layer created by layers of dead keratin that can withstand wear and tear of the outer environment, the dermis provides the epidermis with [[blood]] supply and has [[Neurone|nerves]] that bring danger to attention amongst other functions; hypodermis provides physical cushioning to any mechanical trauma through adipose storage; glands secrete protective films throughout the body; nails protect the digits;  hairs throughout the body filter harmful particles from entering the eyes, ears, nose, etc.
 
*'''''Protection'''''<i>- </i>The skin is the first line of defense against foreign pathogens
*'''''Excretion'''''- Of salt, water and waste products through glands
*'''''Thermoregulation'''''<i>- </i>Via vasocontriction and vasodialtion mechanisms
*'''''Calcium Metabolism'''''<i>- </i>Vitamin D<sub>3 </sub>and Calcitrol
*'''''Fat Stroage'''''<i>&nbsp;</i>
*'''''Sensation'''''<i>- </i>Touch, pressure, pain, and temperature
 
If not working correctly, each of the functions can have important clinical implications and all should be considered when working with patients. For example an important clinical association with the breakdown of the ability of the skin to provide protection is pressure sores.
 
<br>
 
== Structure of the Skin  ==
 
=== Epidermis  ===
 
The epidermis is composed of a series of layers containing stratified keratinised squamous epitelial cells and is the uppermost surfaces of the skin. The epidermis is avascular and relies upon the lower dermis (dermal layer) for oxygenation and metabolism&nbsp;<ref name="p3" />. There are 4 main types of cells within the epidermis<ref name="p3" />;
 
#'''Keratinocytes''' which make up 90% of the cells and is why skin is waterproof
#'''Melanocytes''' which make up 8% of the cells and are responsible for producing the skin pigment, melanin.
#'''Langerhans''' cells which make up 1% of the cells and are involved in the immune response
#'''Merkel cells''' &nbsp;which make up 1% of the cells and function in the sensation of touch
 
The epidermis is made up of the following layers (from bottom to top);
 
#'''Stratum Basale''' (or Stratum Germinativum)
#'''Stratum Spinosum'''
#'''Stratum Granulosum'''
#'''Stratum Lucidum'''
#'''Stratum Corneum'''
 
[[Image:Skinlayers.png|frame|right|332x329px|A diagram Showing the Layers of the Epidermis]]As the skin matures, the layers progress to the surface and are a clear, visible example of the effects of cell maturation and aging until they are finally shed.
 
<br>
 
==== Stratum Basale  ====
 
This is deepest layer layer of the epidermis and is made up of a single row of columnar keratinocytes along with melanocytes and markel cells. The basale is the only layer within the epidermis which is able to divide through mitosis. It is the keratinocytes which undergo this mitosis, producing two daughter cells, one of which remains in the basale and the other migrates and matures to the surface progressing through the layers in a process which takes up to 28 days&nbsp;<ref name="p3" />. As the stratum basale is the closest layer to the dermis and therefore blood and nutrient supply, as the daughter cells mature and move away from this layer, they recieve less nutrition and subsequnelty die. Additionally the cells become more keratinised as they mature as they accumulate more of the fibrous protein keratin meaning they become more capable of protection as they mature. In healthy skin the balance of cells of formation and matration of cells is in balance&nbsp;<ref name="p3" />.<br>
 
==== Stratum Spinosum  ====
 
As one of the daughter cells, produced by the stratum basale, mature and progress to this layer they cannot divide and also become rounded and spikier (hence the name spinosum). This layer is 5-12 cells thick and the cells are connected by intercellular bridges called desmosomes and as the cells progress through the layers these connections are continually being broken and reformed <ref name="pringle">Pringle F, Penzer R. Normal Skin: its function and care. In: Penzer, R editor. Nursing Care of the Skin. Oxford: Butterworth Heinemann, 2002. p20-45.</ref>. These connections have a thorn like projections which draw cells together, contributing to the tensile strength and elasticity of the skin&nbsp;<ref name="Thibo">Thibodeau GA, Patton KT. Structure and Function of the Body. 14th ed. Missouri: Mosby. 2012.</ref>.<br>
 
==== Stratum Granulosum&nbsp;  ====
 
After passing through the basale and spinosum, the cells then reach the granulosum. As they progress to this layer they become longer and flattened to form the 3-5 cells thick granulosum. In this layers the cells undergo apoptosis and are unable to form any metabolic function and as the cells lose their nuclues they become keratinised and are completely made of karatin&nbsp;<ref name="One">Martini FH, Nath, JL. Fundamentals of Anatomy and Physiology. 8th ed. Pearson. San Francisco: Benjamin Cummings. 2009</ref>.&nbsp;At the transition between this layer and the stratum corneum, cells secrete lamellar bodies (containing lipids and proteins) into the extracellular space. This results in the formation of the hydrophobic lipid envelope responsible for the skin's barrier properties <ref name="Ovaere">Ovaere P, Lippens S, Vandenabeele P, Declercq W. The emerging roles of serine protease cascades in the epidermis. Trends in Biochemical Sciences. 34: 2009;453–463</ref>.&nbsp;
 
==== Stratum Lucidum  ====
 
This layer is only found on areas of the body which have high levels of wear and pressure and is needed to be thick such as palms and heels. The lucidum is made up of 3-5 layers of clear, dead keratinocytes which are flattened and highly durable and also has a 'glassy' clear appearance&nbsp;<ref name="p5" />.<br>
 
==== Stratum Corneum ====
 
This is the '''cast off layer''' as this is the uppermost layer of the skin and consists of 25-30 layers of flat, dead keratinocytes and has a thickness between 10 and 40 μm.&nbsp;These cells are arranged in vertical stacks which are firmly connected to each other by a lipid (sort of cell cement) created in the stratum granulosum . As the cells move through the corneum they become less sticky and are shed in lumps known as '''squamae '''in a process known as&nbsp;'''desquamation'''&nbsp;<ref name="p5" />. The thickness of the stratum corneum varies throughout the body. In the palms of the hands and the soles of the feet this layer is typically thicker, since these regions require additional protection in order to grasp objects and avoid injury. If the skin is exposed to constant or high levels of friction, then it is the stratum corneum which adapts and forms a hard callus and this demonstrates this layers primary function of protection.&nbsp;<br>


=== Dermis ===
*[[Immune System|Immunity]]: The skin is the body’s first line of defense acting as a physical barrier preventing direct entry of pathogens. Antimicrobial peptides (AMPs) and lipids on the skin also act as a biomolecular barrier that disrupts [[Bacterial Infections|bacterial]] membranes. Resident immune cells, both [[Leukocytes|myeloid]] and [[Lymphatic System|lymphoid]] cells are present in the skin, and some, eg Langerhans cells or dermal dendritic cells, can travel to the periphery and activate the greater [[Immune System|immune system]]<ref name=":0" />
*[[Wound Healing|Wound healing]]: When our body undergoes trauma with a resulting injury, the integumentary system orchestrates the wound healing process through hemostasis, inflammation, proliferation, and remodeling.<ref name=":0" /><ref name=":0" />
*Thermoregulation: The skin has a large surface area that is highly vascularized, which allows it to conserve and release heat through vasoconstriction and vasodilation, respectively<ref name=":0" />.
*Vitamin D synthesis: The primary sources of vitamin D are sun exposure and oral intake (crucial for bone health)<ref name=":0" />.
*Sensation- Skin innervation is by various types of sensory nerve endings that discriminate pain, temperature, touch, and vibration. Each type of receptor and nerve fiber varies in its adaptive and conductive speeds, leading to a wide range of signals that can be integrated to create an understanding of the external environment and help the body to react appropriately<ref name=":0" />.
== Organ Systems Involved  ==
== Skin ==
* [[File:Integumentary system - Kenhub.png|alt=Overview of the integumentary system|right|frameless|600x600px|Overview of the integumentary system]]Accounts for about 16% of your total body weight. Its surface area covers between 1.5-2m<sup>2&nbsp;</sup><ref name="One">Martini FH, Nath, JL. Fundamentals of Anatomy and Physiology. 8th ed. Pearson. San Francisco: Benjamin Cummings. 2009</ref>
* Made up of two layers—the superficial epidermis and the deeper dermis.
Epidermis:
* Tough, outer layer that acts as the first line of defense against the external environment
* Regenerates from stem cells located in the basal layer that grow up towards the corneum. The epidermis itself is devoid of blood supply and derives its nutrition from the underlying dermis
Image: Overview of the integumentary system<ref > Overview of the integumentary system image -  © Kenhub https://www.kenhub.com/en/study/anatomy-of-integumentary-system</ref>


The dermis lies beneath the epidermis and above the subcutaneous fat layer and, as mentioned above, is responsible for providing nutrients and blood supply to the epidermis&nbsp;<ref name="Burr">Burr S, Penzer R. Promoting Skin Health.Nursing Standard. 2005; 19: 57-65.</ref>. The dermis contains all of the appendages such as the lymph vessels, nerve endings, hair follicles and glands&nbsp;<ref name="pringle" />. The dermis is anchored to the epidermis by rete ridges (furrows) created by hemidesmosomes, which stabilise the surfaces and allow transfer of nutrients between the layers&nbsp;<ref name="Turkington">Turkington C, Dover JS. Skin Deep. 3rd ed. New York: Checkmark Books. 2007.</ref>. If there is a shearing force or a high level of friction on these ridges and between the two layers, the two layers may become separated and fluid allowed to collect in the space forming a blister.
Composed of stratified squamous epithelial cells that further break down into four to five layers (see image R). From superficial to deep, the primary layers are the
* Stratum corneum
* Stratum granulosum
* Stratum spinosum
* Stratum basale
* In the palms and soles where the skin is thicker, there is an additional layer of skin between the stratum corneum and stratum granulosum called the stratum lucidum.
Dermis
* Underlying connective tissue framework that supports the epidermis
* The dermis as a whole contains blood and lymph vessels, nerves, sweat glands, hair follicles, and various other structures embedded within the connective tissue.
Further subdivides into two layers
* Superficial papillary dermis -  forms finger-like projections into the epidermis, known as dermal papillae, and consists of highly vascularized, loose connective tissue.
* Deep reticular layer -  has dense connective tissue that forms a strong network<ref name=":0" />. 
[[File:Burn Hand.jpg|right|frameless]]
Pathophysiology and Injury eg
* Burns eg [[Rehabilitation of Hand Burn Injuries|of the hand]]
* [[Psoriatic Arthritis]]
* [[Epidermolysis Bullosa]]
* [[Cellulitis]] 
* [[Oncology|Cancer]] eg [[Malignant Melanoma|melanona]]
* [[Pressure Ulcers|Pressure Sore]]
* [[Wound Assessment|Wounds]]
== Hypodermis ==
The hypodermis lies between the dermis and underlying organs.
* Commonly referred to as subcutaneous tissue
* Composed of loose areolar tissue and adipose tissue.
* Provides additional cushion and insulation through its function of fat storage and connects the skin to underlying structures such as muscle<ref name=":0" />.


The dermis is made up of two layers called the '''''reticular''''' and '''''papillary''''' layers. the papillary layer contains nerves and capillaries whilst the reticular layer is comprised of the strong connective tissue collagen<ref name="Pringle">Pringle F, Penzer R. Normal Skin: its function and care. In: Penzer, R editor. Nursing Care of the Skin. Oxford: Butterworth Heinemann. 2002;20-45</ref>. &nbsp;<br>  
== Hair  ==
[[File:Hair.jpg|right|frameless]]
Hair is a component of the integumentary system and extends downward into the dermal layer where it sits in the hair follicle.
* The presence of hair is a primary differentiator of mammals as a unique class of organisms.
* In humans, it is a cherished and highly visible indicator of health, youth, and even class.
* It has a sensory function, protects from cold and UV radiation.
* Areas of clinical significance include diseases of hair loss, excess, alterations due to nutritional deficiencies, infectious causes, and effects of drug reactions<ref>Hoover E, Alhajj M, Flores JL. [https://www.ncbi.nlm.nih.gov/books/NBK499948/ Physiology, Hair.] InStatPearls [Internet] 2019 Aug 10. StatPearls Publishing.Available from:https://www.ncbi.nlm.nih.gov/books/NBK499948/ (last accessed 23.10.2020)</ref>


== Links to other Areas or Topics to Consider  ==
== Nail ==
[[File:Nails.jpg|right|frameless]]


*Burns
* Nails form as layers of keratin and appear at the dorsal tips of the fingers and toes.
*[[Pressure Ulcers|Pressure Sores]]
*[[Pain Mechanisms|Pain]]
*Skin Grafts
*Trauma
*[[Diabetes|Diabetes Mellitus]]
*[[Corticosteroid Medication|Corticosteroids]] and other medications<br>
*Patient interaction
*Psychological impact of skin disorders


== Other Resources  ==
* Nails function to protect the fingers and toes while increasing the precision of movements and enhancing sensation.
*[[Effects of Ageing on Hand Function|Pathophysiology]]: [[The Aged Foot|Onychomycosis]] (fungal infection,common clinical presentation involves nail discoloration, subungual hyperkeratosis, onycholysis, and splitting or destruction of the nail plate), Pitting (presents in conditions such as psoriasis, eczema) Koilonychia (spoon nail, been associated with iron deficiency anemia but can be due to idiopathic changes) Clubbing (the most common manifestation of hypertrophic osteoarthropathy and correlates with many systemic conditions).<ref name=":0" />


{{#ev:youtube|R7_arNsaxPs|300}}
== '''Associated Glands''' ==
Four types of exocrine glands within human skin—Sweat, sebaceous, ceruminous, and mammary glands.


*[http://www.britishskinfoundation.org.uk/SkinInformation/AtoZofSkinDisease.aspx www.britishskinfoundation.org.uk/SkinInformation/AtoZofSkinDisease.aspx]&nbsp;[http://www.britishskinfoundation.org.uk/SkinInformation/AtoZofSkinDisease.aspx]
Sweat glands, are further divided into eccrine and apocrine glands.
* Eccrine glands are distributed throughout the body and primarily produce serous fluid to regulate body temperature.
* Apocrine glands are present in the axilla and pubic area and produce milky protein-rich sweat. These glands are responsible for odor as bacteria break down the secreted organic substances.
Sebaceous glands are part of the pilosebaceous unit, which includes the hair, hair follicle, and arrector pili muscle.
* Secretes an oily substance called sebum, a mixture of lipids that forms a thin film on the skin.  
* This layer adds a protective layer, prevents fluid loss, and also plays an antimicrobial role<ref name=":0" />.
Pathophysiology eg Seborrheic dermatitis, Hyperhidrosis
== Conclusion  ==
The integumentary system provides numerous functions necessary for human life while also maintaining an optimal internal environment for other critical components to thrive. 
* When there is an imbalance in this system, many disorders can manifest.  
* The integumentary system also acts as a reflection of underlying pathologies eg showing jaundice with liver disfunction, displaying petechiae with thrombocytopenia; decreased skin turgor with [[Dehydration|dehydration.]]
* It is a system that can provide many external clues regarding an individual’s physiological state and is a vital component of a complete clinical picture<ref name=":0" />.


== References  ==
== References  ==
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[[Category:Healing]]
[[Category:Older People/Geriatrics - Outcome Measures]]

Latest revision as of 05:22, 24 March 2022

Original Editor - Scott Buxton

Top Contributors - Scott Buxton, Lucinda hampton, Wendy Walker, Admin, Kim Jackson, WikiSysop, Joao Costa, 127.0.0.1 and Vidya Acharya  

The Integumentary System[edit | edit source]

Skin blank.jpg

The integumentary system is the largest organ of the body that forms a physical barrier between the external environment and the internal environment that it serves to protect and maintain.

The integumentary system includes

  • Skin (epidermis, dermis)
  • Hypodermis
  • Associated glands
  • Hair
  • Nails.

In addition to its barrier function, this system performs many intricate functions such as body temperature regulation, cell fluid maintenance, synthesis of Vitamin D, and detection of stimuli. The various components of this system work in conjunction to carry out these functions[1].

General Function[edit | edit source]

The integumentary system has several functions that provide several purposes[2]:

Wound botulism.jpg
  • Physical protection: The integumentary is the covering of the human body and its' most apparent function is physical protection: skin - a tightly knit network of cells, with each layer contributing to its strength. The epidermis has an outermost layer created by layers of dead keratin that can withstand wear and tear of the outer environment, the dermis provides the epidermis with blood supply and has nerves that bring danger to attention amongst other functions; hypodermis provides physical cushioning to any mechanical trauma through adipose storage; glands secrete protective films throughout the body; nails protect the digits; hairs throughout the body filter harmful particles from entering the eyes, ears, nose, etc.
  • Immunity: The skin is the body’s first line of defense acting as a physical barrier preventing direct entry of pathogens. Antimicrobial peptides (AMPs) and lipids on the skin also act as a biomolecular barrier that disrupts bacterial membranes. Resident immune cells, both myeloid and lymphoid cells are present in the skin, and some, eg Langerhans cells or dermal dendritic cells, can travel to the periphery and activate the greater immune system[1]
  • Wound healing: When our body undergoes trauma with a resulting injury, the integumentary system orchestrates the wound healing process through hemostasis, inflammation, proliferation, and remodeling.[1][1]
  • Thermoregulation: The skin has a large surface area that is highly vascularized, which allows it to conserve and release heat through vasoconstriction and vasodilation, respectively[1].
  • Vitamin D synthesis: The primary sources of vitamin D are sun exposure and oral intake (crucial for bone health)[1].
  • Sensation- Skin innervation is by various types of sensory nerve endings that discriminate pain, temperature, touch, and vibration. Each type of receptor and nerve fiber varies in its adaptive and conductive speeds, leading to a wide range of signals that can be integrated to create an understanding of the external environment and help the body to react appropriately[1].

Organ Systems Involved[edit | edit source]

Skin[edit | edit source]

  • Overview of the integumentary system
    Accounts for about 16% of your total body weight. Its surface area covers between 1.5-2m2 [3]
  • Made up of two layers—the superficial epidermis and the deeper dermis.

Epidermis:

  • Tough, outer layer that acts as the first line of defense against the external environment
  • Regenerates from stem cells located in the basal layer that grow up towards the corneum. The epidermis itself is devoid of blood supply and derives its nutrition from the underlying dermis

Image: Overview of the integumentary system[4]

Composed of stratified squamous epithelial cells that further break down into four to five layers (see image R). From superficial to deep, the primary layers are the

  • Stratum corneum
  • Stratum granulosum
  • Stratum spinosum
  • Stratum basale
  • In the palms and soles where the skin is thicker, there is an additional layer of skin between the stratum corneum and stratum granulosum called the stratum lucidum.

Dermis

  • Underlying connective tissue framework that supports the epidermis
  • The dermis as a whole contains blood and lymph vessels, nerves, sweat glands, hair follicles, and various other structures embedded within the connective tissue.

Further subdivides into two layers

  • Superficial papillary dermis - forms finger-like projections into the epidermis, known as dermal papillae, and consists of highly vascularized, loose connective tissue.
  • Deep reticular layer - has dense connective tissue that forms a strong network[1]. 
Burn Hand.jpg

Pathophysiology and Injury eg

Hypodermis[edit | edit source]

The hypodermis lies between the dermis and underlying organs.

  • Commonly referred to as subcutaneous tissue
  • Composed of loose areolar tissue and adipose tissue.
  • Provides additional cushion and insulation through its function of fat storage and connects the skin to underlying structures such as muscle[1].

Hair[edit | edit source]

Hair.jpg

Hair is a component of the integumentary system and extends downward into the dermal layer where it sits in the hair follicle.

  • The presence of hair is a primary differentiator of mammals as a unique class of organisms.
  • In humans, it is a cherished and highly visible indicator of health, youth, and even class.
  • It has a sensory function, protects from cold and UV radiation.
  • Areas of clinical significance include diseases of hair loss, excess, alterations due to nutritional deficiencies, infectious causes, and effects of drug reactions[5]

Nail[edit | edit source]

Nails.jpg
  • Nails form as layers of keratin and appear at the dorsal tips of the fingers and toes.
  • Nails function to protect the fingers and toes while increasing the precision of movements and enhancing sensation.
  • Pathophysiology: Onychomycosis (fungal infection,common clinical presentation involves nail discoloration, subungual hyperkeratosis, onycholysis, and splitting or destruction of the nail plate), Pitting (presents in conditions such as psoriasis, eczema) Koilonychia (spoon nail, been associated with iron deficiency anemia but can be due to idiopathic changes) Clubbing (the most common manifestation of hypertrophic osteoarthropathy and correlates with many systemic conditions).[1]

Associated Glands[edit | edit source]

Four types of exocrine glands within human skin—Sweat, sebaceous, ceruminous, and mammary glands.

Sweat glands, are further divided into eccrine and apocrine glands.

  • Eccrine glands are distributed throughout the body and primarily produce serous fluid to regulate body temperature.
  • Apocrine glands are present in the axilla and pubic area and produce milky protein-rich sweat. These glands are responsible for odor as bacteria break down the secreted organic substances.

Sebaceous glands are part of the pilosebaceous unit, which includes the hair, hair follicle, and arrector pili muscle.

  • Secretes an oily substance called sebum, a mixture of lipids that forms a thin film on the skin.
  • This layer adds a protective layer, prevents fluid loss, and also plays an antimicrobial role[1].

Pathophysiology eg Seborrheic dermatitis, Hyperhidrosis

Conclusion[edit | edit source]

The integumentary system provides numerous functions necessary for human life while also maintaining an optimal internal environment for other critical components to thrive. 

  • When there is an imbalance in this system, many disorders can manifest.
  • The integumentary system also acts as a reflection of underlying pathologies eg showing jaundice with liver disfunction, displaying petechiae with thrombocytopenia; decreased skin turgor with dehydration.
  • It is a system that can provide many external clues regarding an individual’s physiological state and is a vital component of a complete clinical picture[1].

References[edit | edit source]

  1. ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 Kim JY, Dao H. Physiology, Integument. InStatPearls [Internet] 2020 Feb 17. StatPearls Publishing.Available from:https://www.ncbi.nlm.nih.gov/books/NBK554386/ (last accessed 23.10.2020)
  2. ↑ Martini FH, Nath, JL. Fundamentals of Anatomy and Physiology. 8th ed. Pearson. San Francisco: Benjamin Cummings. 2009
  3. ↑ Martini FH, Nath, JL. Fundamentals of Anatomy and Physiology. 8th ed. Pearson. San Francisco: Benjamin Cummings. 2009
  4. ↑ Overview of the integumentary system image - © Kenhub https://www.kenhub.com/en/study/anatomy-of-integumentary-system
  5. ↑ Hoover E, Alhajj M, Flores JL. Physiology, Hair. InStatPearls [Internet] 2019 Aug 10. StatPearls Publishing.Available from:https://www.ncbi.nlm.nih.gov/books/NBK499948/ (last accessed 23.10.2020)


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