203 Skin And Osteology Of Lower Limb Flashcards
(25 cards)
The skin is made up of three layers. Name them
Epidermis
Dermis
Hypodermis or subcutaneous fat or superficial fascia (this isn’t seen on gross inspection or anatomy but since you’re using microscope in histology, you will see it)
You get to the superficial fascia after all the layers before you get to the deep layer or fascia which covers the muscles.
Between the dermis and the epidermis,what structures cause interlocking of the two skin layers?
What brings about the square to hexagonal or polygonal shapes on the skin?
On thé Surface on the dermis, there are elevations called dermal papillae.
There are similar elevations at the inner surface of the epidermis called epidermal ridges so the two layers come in contact and interlock with each other
These interlocking firmly holds the epidermis to the dermis.
The epidermis has many downward projections into the dermis, known as epidermal ridges. Likewise, the dermis has alternated upward projections between the epidermal ridges, the dermal papillae. Below the epidermal ridges lies the dermoepidermal junction. This is an acellular zone between the dermis and the epidermis.
The square and hexagonal shapes are due to the interlocking pattern of the structures on the dermis and epidermis.
Derivatives of the skin are the nail and the hair
Which layer of the skin lacks blood vessels?
Epidermis. All the vessels are in the dermis and hypodermis.
Nutrients supply to the epidermis is due to diffusion so the cells of the epidermis closer to the dermis will get nutrients via diffusion from the dermis to the epidermis and the epidermal cells away from the dermis won’t get so those ones are dead cells.
What is exfoliation?
Why does the towel smell so bad when you soak it?
Removal or peeling of dead skin cells.
Cuz there is a breakdown of those dead cells and this produces sulphur content
Breakdown of sulfur containing proteins in the dead cells of the skin is the reason your towel smells after soaking it for some days. When you wipe, your dead cells are removing so they’re on your towel.
The skin is divided into two main types. Thick and thin skin.
Which parts of the body are these found and why are they called so?
State the differences between the epidermis and dermis
Structure of the epidermis accounts for the difference:
Thick : has stratum lucidum and covers the soles of feet and palmar surface.
Everywhere else is thin skin. Thin skin doesn’t have stratum lucidum.
Epidermal layer is thicker in thick skin than in thin skin.
Other differences :
Also, The dermis of thick skin is relatively small compared to that of the thin skin.
Thick skin has a thicker hypodermis than that of the thin skin.
No hair follicles in thick skin but present in thin skin
Thick skin still has sweat glands. Structure and location differentiates them.
Thickness of thin skin isn’t uniform. Some parts of the thin skin are thick.
Which parts of the thin skin are very thick?
Which parts of the thin skin are very thin?
Thinnest form of thin skin are at the eyelids
Thickest form of thin skin is at the interscapular region(between the two scapulae).
Why do the eyelids easily get swollen when there’s trauma?
Thin skin of the eyelids qnd has loose connection with the hypodermis that’s why it easily gets swollen when there’s trauma. Any slight trauma, the dermis separates itself from the hypodermis and is filled with fluid
State the functions of the skin
Explain how the body controls temperatures using the skin
Resistance to trauma and infection:
Arrangement of the cells in the epidermis is highly interlocked by desmosomes and tight junctions that’s why the skin resists infections and trauma
Living part of skin and the sweat,immune cells on the skin and keratinocytes contains chemicals that form acid mantle (a film) on the surface of the skin and the chemicals are demicidins and defensins.
This kills the bacteria. Some bacteria still survive on the skin and don’t get access to the skin unless there’s a cut on the skin. They get nutrients from the dead cells. So they live on the skin. That’s why you use spirit on the skin before you puncture the skin. To kill those bacteria.
Skin retains water:
Vitamin D synthesis:
Vitamin D synthesis:initiation for synthesis occurs in skin and finishes in liver and kidneys. Small of vit D is from diet.
Sensation: skin has plenty nerve endings but the nerve endings are more concentrated at where the skin is pointing like the lips, the fingers and toes, tip of the nose, nipples, tip of penis
Non verbal communication:facial expressions, blinking of eyelids.
thermoregulation:
In a hot environment, heat is absorbed into the body cuz heat moves from high temp to low temp.
The body expels heat coming into it via vasodilation via dilation of blood vessels in the dermis. It also activates sweat production and sweat will evaporate and evaporation requires heat energy so as it’s evaporating, heat is going.
In cold environments, body loses it and conserves heat by constricting vessels to prevent more blood from
Coming to the skin and deactivated sweat glands.
Great! Below are the flashcard-style questions first. You can test yourself with these, and I’ll follow up with the questions and answers in the next message.
🟫 Skin Defense Flashcards – Questions Only
1. What cell junctions help tightly link epidermal cells together to resist trauma?
2. What junctions seal the space between epidermal cells to prevent pathogen entry?
3. Which outermost layer of the epidermis acts as the primary physical barrier?
4. What is the name of the acidic film on the skin that prevents microbial growth?
5. Which glands produce dermcidin?
6. What type of molecules are defensins and dermcidin?
7. Which cells in the epidermis can release cytokines and contribute to immune responses?
8. Which immune cells in the stratum spinosum act as antigen-presenting cells?
9. Which cells in the epidermis and dermis contribute to long-term immune memory?
10. What is the average time it takes for the skin to renew itself?
11. What process helps remove microbes attached to dead skin cells?
12. What happens when the skin barrier is disrupted, such as in eczema or burns?
13. Which AMP is produced by keratinocytes and neutrophils and destroys microbial membranes?
14. What is the “brick and mortar” model in the context of the skin barrier?
15. Name two antimicrobial peptides found on the skin.
Skin retains water. How?
Awesome! Here’s the second part—questions with answers to help you study:
🟩 Skin Defense Flashcards – Questions and Answers
1. What cell junctions help tightly link epidermal cells together to resist trauma?
➤ Desmosomes
2. What junctions seal the space between epidermal cells to prevent pathogen entry?
➤ Tight junctions
3. Which outermost layer of the epidermis acts as the primary physical barrier?
➤ Stratum corneum
4. What is the name of the acidic film on the skin that prevents microbial growth?
➤ Acid mantle
5. Which glands produce dermcidin?
➤ Eccrine sweat glands
6. What type of molecules are defensins and dermcidin?
➤ Antimicrobial peptides (AMPs)
7. Which cells in the epidermis can release cytokines and contribute to immune responses?
➤ Keratinocytes
8. Which immune cells in the stratum spinosum act as antigen-presenting cells?
➤ Langerhans cells
9. Which cells in the epidermis and dermis contribute to long-term immune memory?
➤ Resident T cells
10. What is the average time it takes for the skin to renew itself?
➤ About 28 days
11. What process helps remove microbes attached to dead skin cells?
➤ Desquamation (shedding of dead skin cells)
12. What happens when the skin barrier is disrupted, such as in eczema or burns?
➤ Increased risk of infection and loss of protective function
13. Which AMP is produced by keratinocytes and neutrophils and destroys microbial membranes?
➤ Defensins
14. What is the “brick and mortar” model in the context of the skin barrier?
➤ Corneocytes = bricks; Lipids = mortar – describes how the stratum corneum is structured
15. Name two antimicrobial peptides found on the skin.
➤ Dermcidin and defensins (also: cathelicidins like LL-37)
Would you like these in a printable format or a digital quiz version?
Yes, your original information is accurate, and there is more detail that can help you fully understand how the skin resists trauma and infection. Below is a verified and expanded explanation, including all major players involved in skin defense:
✅ Skin Defense: Detailed and Accurate Explanation
- Physical and Structural Barrier
• Epidermal cell arrangement:
• The keratinocytes in the epidermis are packed closely together in multiple layers.
• Desmosomes connect adjacent keratinocytes, giving mechanical strength to the skin.
• Tight junctions, especially in the stratum granulosum, seal the spaces between cells to prevent pathogen entry.
• The stratum corneum (outermost layer):
• Made of dead, flattened keratinocytes (corneocytes) embedded in lipid matrix.
• Acts like a “brick and mortar” model—corneocytes (bricks) + lipids (mortar).
• It is waterproof, resilient, and forms the first line of defense against abrasion and microbes. - Chemical Barrier
• The acid mantle:
• A thin acidic film (pH 4.5–5.5) formed by sweat, sebum, and epidermal lipids.
• Inhibits growth of pathogenic bacteria and fungi.
• Antimicrobial peptides (AMPs):
• Dermcidin: Secreted by eccrine sweat glands; broad-spectrum antimicrobial.
• Defensins: Secreted by keratinocytes and neutrophils; insert into microbial membranes causing cell lysis.
• Cathelicidins (e.g., LL-37): Another AMP produced by keratinocytes and immune cells. - Immunological Barrier
• Keratinocytes:
• Not just structural—they also produce cytokines and chemokines in response to injury or pathogens.
• Langerhans cells (in stratum spinosum):
• Specialized dendritic antigen-presenting cells that detect pathogens and activate the immune system.
• Resident T cells:
• Present in the epidermis and dermis—help in long-term immune memory and pathogen defense.
• Mast cells, macrophages, dendritic cells:
• Found in the dermis, help in inflammation and pathogen destruction. - Mechanical and Regenerative Defense
• Skin is renewed regularly (~every 28 days), which helps:
• Shed dead cells (desquamation), removing microbes attached to them.
• Maintain the strength and integrity of the barrier.
• Wound healing response:
• Rapidly triggered by injury to restore barrier function and recruit immune cells.
✅ Summary: Why the Skin Resists Infections and Trauma
Barrier Type Key Components Function
Structural/Physical Keratinocytes, Desmosomes, Tight Junctions, Stratum Corneum Resist trauma, prevent pathogen entry
Chemical Acid Mantle, Dermcidin, Defensins, Cathelicidins Kill/inhibit microbes
Immunological Langerhans cells, T-cells, Cytokines, Immune surveillance Detect, present, and destroy pathogens
Mechanical/Regenerative Shedding, Wound healing Remove infected cells and repair quickly
🧠 Clinically Relevant Tip:
• Damage to the skin barrier (e.g., burns, eczema, very dry skin) increases the risk of infections because it compromises one or more of these defense layers.
Would you like flashcards, quiz questions, or a simplified visual summary to help with memorization?
What muscle makes the hair follicles erect in cold conditions
What does this erection do to help ?
Arrector Pili Muscles and Thermoregulation
• Arrector pili are small smooth muscles attached to hair follicles in the dermis.
• They are innervated by the sympathetic nervous system.
• When stimulated (e.g., by cold or emotional stress), these muscles contract, causing:
• Hair to stand upright (piloerection or “goosebumps”).
• A small layer of air to be trapped between the hairs and the skin.
• This trapped air acts as insulation, helping to retain body heat, not cool it.
• So, the purpose is to prevent heat loss, not to cool the body.
Why Trapping Air Reduces Heat Loss – Short Summary:
Trapping air near the skin helps reduce heat loss because air is a poor conductor of heat. When arrector pili muscles make hairs stand up, they trap a thin layer of still air close to the body. This layer acts as insulation, slowing down the transfer of body heat to the colder environment and helping to conserve warmth.
What determines skin color?
State the two main forms
Of skin pigments and state their colors.
Determined by melanin which is a pigment from melanocytes in the epidermis.
Types of pigment:
Pheomelanin is yellowish red. Eumelanin is blackish brown
Concentration of these two controls the kind of skin color you get. It’s controlled by genes and environment(to protect from UV)
Excess radiations in an environment means more melanin by the melanin genes so you can have genes for more melanin but you won’t show the thing cuz your environment isn’t harsh
Other types of
Pigments that give skin color or determine skin color:
hemoglobin and carotene.
Where is melanin deposited and produced?
Produced by melanocytes.
Picked up by keratinocytes
How does hemoglobin and carotene control skin color
What’s the name of the skin pathology tjay occurs when carotene isn’t metabolized?
Areas with thin epidermis for blood capillaries( containing hemoglobin which gives red color)in the dermis will be exposed, that area in the epidermis is transparent so you see the dermis. The color there will be pinkish. Example is lips.
Carotene is a yellowish substance found in fruits like carrots oranges. Mixes with blood and temporarily causes change in skin until it’s metabolized
In some people, it’s retained in the skin in pathological conditions and looks yellow . Example is corn tjay appears under the feet which is characterized by accumulation of dead cells and appears yellowish due to keratinocytes picking the carotene pigment.
Carotene and Skin Color – Clarified Explanation
• Carotene is a yellow-orange pigment found in orange-colored fruits and vegetables like carrots, sweet potatoes, and oranges.
• It is fat-soluble and tends to accumulate in the stratum corneum (especially in thick skin like the palms and soles) and subcutaneous fat.
• High intake can cause a harmless condition called:
Carotenemia – a yellow-orange discoloration of the skin, especially noticeable in the palms and soles.
• It may look similar to jaundice but does not affect the sclera (white of the eyes).
• In some pathological or metabolic conditions, carotene may be retained longer in the skin.
• The yellow discoloration is especially visible in areas with thicker keratin, like the stratum corneum of the soles and palms.
✅ Key Term:
• Carotenemia (or carotenoderma):
A non-toxic condition due to excess carotene in the diet or metabolic retention, causing yellowing of the skin, especially on palms and soles.
Would you like a flashcard for this or a side-by-side comparison of carotenemia vs jaundice?
State five highly pigmented areas relative to the rest of the skin.
What’s the difference between freckles and moles.
Blood clot in the dermis due to trauma causes what skin pathology?
Accumulation of blood in the dermis of the skin is what causes what disorder of pigmentation?
Areas that are highly pigmented:
Scrotum skin is highly pigmented compared to the thighs and folded cuz the muscle stretches and recoils
Areola of the breast or the nipples
Anal orifice
Labia majora
Where there are joints or where flexion occurs example is knee and skin on elbow areas , back of skin when you extend the fingers cuz they’re exposed to stretching causing plenty pressure there so skin responds by producing plenty melanin
Darkened patches on the skin due to excess melanin production are called freckles. If the freckles are raised, it’s called a mole.
Cyanosis : bluish color due to low oxygen
A Blood clot in the dermis due to trauma is what causes a hematoma.
Accumulation of blood in the dermis of the skin is what causes erythema. Erythema looks like mosquito bites which are reddened
Jaundice can be due to spleen destroying the rbcs plenty cuz the spleen checks the integrity of the rbcs so older rbcs can’t pass through the mesh of the spleen so they’re destroyed but in spleen problem, both new and old rbcs are destroyed
When you’re young, the skin glows so you have a smooth skin but as you grow older
What causes wrinkling and plenty pigmentation in older people?
Older people have thermorégulation issues too
Integrity of skin is a problem
Collagen fiber breakdown and blood vessels breakdown and the body just can’t repair it properly as it would at first cuz you’re getting older .
Break down of collagen fibers causes wrinkling and less of blood vessels causes scaly patches cuz there’s more dead cells that usual
✅ Why Skin Wrinkles and Develops Pigmentation with Age
🧬 1. Collagen and Elastin Breakdown
• As you age, fibroblasts in the dermis produce less collagen and elastin.
• Existing collagen fibers break down, and elastin becomes disorganized and fragmented.
• This leads to:
• Loss of firmness and elasticity
• Wrinkling and sagging of skin
🩸 2. Reduced Blood Supply
• Aging causes thinning and reduced density of dermal blood vessels.
• Less oxygen and nutrients reach the skin → slower healing and regeneration
• This contributes to:
• Dry, scaly patches
• More visible dead skin cells
• Paler or uneven skin tone
☀️ 3. Pigmentation Changes
• Melanocyte activity becomes uneven with age.
• Some areas produce excess melanin, leading to:
• Age spots or liver spots (solar lentigines)
• Chronic sun exposure (photoaging) accelerates this process.
🛠 4. Slower Repair and Regeneration
• Cell turnover in the epidermis slows down.
• Wound healing is delayed, and the skin becomes thinner and more fragile.
• Dead cells accumulate, making the skin look dull and rough.
✅ Summary of Age-Related Skin Changes:
Factor Effect on Skin
↓ Collagen & elastin Wrinkles, sagging
↓ Blood vessels Poor healing, dry/scaly patches
Uneven melanin Pigmentation spots
↓ Cell turnover Dull, rough skin
Sun damage Accelerated aging (photoaging)
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What type of gland is the breast classified as?
2. What structures make up the glandular part of the breast?
3. What is the function of a lactiferous duct?
4. Where do lactiferous ducts open?
5. What holds the lobules of the breast in position?
6. What muscle fascia do the suspensory ligaments attach to?
7. What is the retromammary space and its function?
8. Why is the breast not firmly attached to the chest wall?
9. What contributes to breast size in relation to collagen?
10. What happens to collagen fibers with aging?
11. What two factors lead to breast sagging over time?
12. Where is the clavipectoral fascia in relation to the breast?
State the Layered Anatomy of the Anterior Chest Wall (from superficial to deep):
Q: What type of gland is the breast classified as?
A: A mammary gland and a modified sweat gland.
2. Q: What structures make up the glandular part of the breast?
A: Lobules, which contain the milk-producing glands.
3. Q: What is the function of a lactiferous duct?
A: It carries milk from each lobule to the nipple.
4. Q: Where do lactiferous ducts open?
A: Each duct opens independently at the nipple.
5. Q: What holds the lobules of the breast in position?
A: Suspensory ligaments (of Cooper).
6. Q: What muscle fascia do the suspensory ligaments attach to?
A: The deep fascia of the pectoralis major muscle.
7. Q: What is the retromammary space and its function?
A: A small space between the breast and pectoralis major that allows mobility of the breast.
8. Q: Why is the breast not firmly attached to the chest wall?
A: Because of the presence of the retromammary space.
9. Q: What contributes to breast size in relation to collagen?
A: More collagen fibers contribute to a fuller or larger breast structure.
10. Q: What happens to collagen fibers with aging?
A: They lose elasticity over time.
11. Q: What two factors lead to breast sagging over time?
A: Loss of collagen fiber elasticity and the effect of gravity.
12. Q: Where is the clavipectoral fascia in relation to the breast?
A: At the superolateral aspect, deep and lateral to the upper outer part of the breast near the axilla.
Skin and aging:
Skin and age related changes in the breast:
Breast is a mammary gland and a modified sweat gland
It consists of lobules
Each lobule has a duct called lactiferous duct
Each duct opens independently at the nipple
All these lobules are bound by suspensory
Ligaments of cooper of the breast which fuse with the deep fascia of the pectoralis major muscle and suspends breast and holds it in position via attachment to pectoralis major.
There is a small space called retromammary space between the breast and the muscle that allows the breast to be moved that’s why it’s not firmly attached to the pectoralis major.
More collagen fibers means bigger breast
Elasticity of the duspeonsory lifaments and collagen fibers reduce with time plus gravity acting on the breast leading to breast sagging
Layered Anatomy – Anterior Chest Wall (from superficial to deep):
Layer Location
Skin Outermost layer
Breast tissue (glandular & fat) Lies on top of the pectoralis major muscle
Retromammary space Loose connective tissue between breast and pectoral fascia
Pectoral fascia Covers pectoralis major
Pectoralis major muscle Main anterior chest muscle
Clavipectoral fascia Lies deep to pectoralis major, in the superolateral quadrant, especially in the axilla region, between pectoralis minor and subclavius muscle
Ribs & intercostal muscles Deepest layers under fascia and muscles
What is skin turgor?
2. What does normal skin turgor look like when the skin is pinched and released?
3. What does it mean when the skin remains elevated after being pinched?
4. What clinical condition can reduced skin turgor indicate?
When you pinch the skin, it has to go back to normal. That’s turgor.
Skin is supposed to be mobile against underlying tissues
Skin must go back to its normal state. It’s not supposed to remain elevated after being pulled up and released : that is turgor
Skin turgor refers to the skin’s elasticity and ability to return to its normal shape after being gently pinched and released. It reflects the skin’s hydration status and connective tissue health.
• When skin is healthy and well-hydrated, it quickly returns to its normal position.
• If the skin stays elevated or slowly returns, this indicates reduced turgor, commonly seen in dehydration, aging, or sometimes edema.
• Although edema is excess fluid in tissues, chronic or pitting edema can stretch the skin and interfere with elasticity, making turgor assessment less reliable.
Turgor can be reduced due to edema
Q: What is skin turgor?
A: Skin turgor is the skin’s ability to return to its normal shape after being pinched and released.
2. Q: What does normal skin turgor look like when the skin is pinched and released?
A: The skin quickly returns to its original position.
3. Q: What does it mean when the skin remains elevated after being pinched?
A: It suggests reduced skin turgor, often due to dehydration or poor skin elasticity.
4. Q: What clinical condition can reduced skin turgor indicate?
A: Dehydration, aging, or poor skin elasticity.
5. Q: Can edema affect skin turgor?
A: Yes, chronic or severe edema can reduce the accuracy of turgor by stretching or stiffening the skin.
What are dermatomes?
The highest point of the head is called? What nerve supplies it
Which nerve supplies the tip of the nose?
5. Which nerve supplies the upper lip?
6. Which nerve supplies the lower lip and chin?
7. What dermatome corresponds to the top of the head (vertex)?
8. What dermatome supplies the skin surrounding the anal orifice?
9. What dermatome supplies the anal orifice itself?
10. Are dermatomes the same as cutaneous nerves?
A dermatomes is Area of skin supplied by single spinal or cranial nerve
Cutaneous is different from dermatomes
Example: the medial aspect of arm is supplied by medial cutaneous nerve of the arm and that’s the nerve but the root of this nerve is the dermatome.
The highest point of the head is called vertex. Vertex of the skull = The highest point on the scalp when the head is in anatomical position.
This area is typically supplied by the C2 dermatome.
What is a cutaneous nerve?
A: A peripheral nerve that supplies the skin with sensory innervation, often containing fibers from multiple spinal roots.
3. Q: Do dermatomes and cutaneous nerve distributions always match?
A: No, they often differ because cutaneous nerves may carry fibers from more than one spinal root.
4. Q: Which nerve supplies the tip of the nose?
A: The ophthalmic branch (CN V1) of the trigeminal nerve.
5. Q: Which nerve supplies the upper lip?
A: The maxillary branch (CN V2) of the trigeminal nerve.
6. Q: Which nerve supplies the lower lip and chin?
A: The mandibular branch (CN V3) of the trigeminal nerve.
7. Q: What dermatome corresponds to the top of the head (vertex)?
A: C2 dermatome.
8. Q: What dermatome supplies the skin surrounding the anal orifice?
A: S4.
9. Q: What dermatome supplies the anal orifice itself?
A: S5.
10. Q: Are dermatomes the same as cutaneous nerves?
A: No, dermatomes are based on spinal roots; cutaneous nerves are named peripheral nerves that may carry multiple root fibers.
What are the tragus and antitragus, and where are they located?
2. How can the head be divided into anterior and posterior parts using surface landmarks?
3. Which anatomical structures does the dividing line pass through when separating the head into anterior and posterior portions?
4. What is the vertex of the head, and why is it used as a surface landmark?
All areas anterior to the imaginary line that divides the skill is innervated by what cranial nerve?
Which part of this nerve supplies the when you follow the superior temporal line all to the corner of the eyes and it’ll divide the upper and lower eyelids (so this nerve supplies the upper eyelid not the lower) and to dorsum of the nose up to the tip of the nose
Which nerve supplies the lower eyelid, corner of the mouth(still drawing a lien from the superior temporal line to that corner of the mouth),to the upper lip?
Which nerve supplies everywhere else on the dace(lower lip, anterior aspect of the ear
Study dermatomes map and make proper questions W
What is the tragus?
A1: A small cartilaginous projection in front of the external auditory canal. It’s part of the anterior part of the skull
Q2: What is the antitragus?
A2: A small bump opposite the tragus, just above the earlobe. Part of posterior part of the skull
Q3: Describe how the head can be divided into anterior and posterior parts using surface anatomy.
A3: By drawing a line from the vertex of the skull to the superior margin of the ear, across the external ear, angle of the mandible, and along the inferior border of the mandible.
Q4: What is the significance of the vertex in surface anatomy?
A4: It is the highest point on the skull and serves as a landmark for dividing the head in anatomical and clinical assessments.
If you draw a line from the vertex of the head to the superior margin of the ear and drawn to divide the ear anterior and posterior parts across the angle or ramus of the mandible and the inferior border of the mandible will separate the skull into the anterior and posterior portion.
nerve.
All areas anterior to the imaginary line that divides the skull is innervated by what cranial nerve? Trigeminal nerve (5th cranial merve). Does skin innervation of the face.
Ophthalmic supplies the forehead, front part of the head, corner of the eye, upper eyelid, dorsum or lateral aspect of nose and tip of the nose
Maxillary- lower eyelid.
Mandibular
The posterior part of the ear along the shoulder to the acromion process and beyond the ramus of the mandible is supplied by this nerves?
What nerve innervates the back of the head?
C3 and C2 spinal accessory nerves (in terms of dermatomes ) also called transverse surgical nerve when talking bout cutaneous innervation
Greater occipital nerve which comes from posterior rami c2
1.When you follow the superior temporal line to the corner of the eyes separating it into upper and lower eyelids to the dorsum or lateral part of the nose and to the top of the nose. What part of the trigeminal nerve innervates this? This nerve innervates only the upper eyelid not the lower eyelid
- So following this same superior temporal line to lower eyelid to the upper lip, and to the corner of the mouth. which nerve supplies this?
- Which nerve supplies the lower lip , anterior aspect of the ear or the tragus, the mandible and the tip of the chin
- Which nerve innervates the posterior part of the ear, antetragus, beyond the ramus of the mandible along the shoulder to the acromnion process?
- Which nerve innervates the occipital region and back of the neck?
- Skin over the parotid gland
• Lower part of the auricle (including the antitragus)
• Angle and ramus of the mandible
• Skin behind the ear
The ophthalmic branch of the trigeminal nerve
2. Maxillary branch of the trigeminal nerve
3. Mandibular branch
4. C2 and C3(in terms of dermatomes). Transverse surgical nerves(in terms of cutaneous innervation) the part about the shoulder to acromion process is more of c3.
5. Greater occipital nerve which is a branch. Of the posterior rami of C2
6.C2-C3
- Which nerve innervates the anterior aspect of the neck
- Between c3 zone and skin above clavicle
3.skin along the acromion process and skin of manubri of sternum and extends to anterolateral aspect of the arm forearm and wrist
4.which nerve innervates the posterior aspect of the arm forearm and ends at the wrist - Which nerve takes care of skin in first intercostal space and continues to the anteromedial aspect of the arm forearm and ends at the wrist
- Which nerves takes care of the skin in the second to the 11th intercostal space?
7.Which nerve goes below the 12th rib? - Which dermatome innervates the nipples?
- Which dermatome innervates the umbilical cord or navel
10.Which takes care of xiphoid process area - Which nerve goes to the inguinal region
12.below the inguinal region, what nerve innervates the mons pubis area, medial
Portion of thigh ?
- C2 and C3
- C4
3.C5 - C6 and 7
- T1. The rest of the intercostal nerves take care of the trunk demarcated according to intercostal spaces
- T2- second intercostal, T3- third intercostal. Same goes for T4-T11
- T12 runs below the 12th rib so it’s sub costal and not in the costal space
8.T4
9.T10
10.T7 and T6 - T12
- L1(also runs with L2 obliquely )
- Which nerve continues to
Medial
Side of the heel from the anterior upper thigh ?
2.Which dermatome? supplies the skin feom the anterior lower thigh to the patellar surface and continues for the medial side to innervate the skin of the medial malleolar? - Below the patellar region,what dermatome takes care of the skin in the anterior part of the leg, lateral leg ad lateral thigh nand dorsum of foot ?
- Which goes to the heel and the lateral side of the foot
- Which dermatome supplies the medial side of the big toe
- Which goes to lateral side of big toe to 2-4th toes
- Which goes to little toe?
- L2,3
- L4
3.L5
4.S1 - L4
- L5
- S1
At the posterior part of the body,which nerve innervates the across the acromion to the posteriolateral part of the arm and forearm and the skin of the pollicis?
2. Posterior arm forearm and elbow and index and middle fingers both dorsal and palmar surface
3.posteromedial aspect of arm and forearm and the ring and little finger
4. What dermatome innervates the gluteal region
5. What about the posteriolateral part of thigh, goes to leg and lateral
Malleolar
6. Posteriomedial part of thigh and leg
7. Anal orifice
8.and surrounding skin of anal orifice
9. Genitals
10. Posteriolateral leg
11. Posterio medial leg
- C6
- C7
- C8 (T1-L5 posterior corresponds with the anterior
- S1, s2,s3
- S1
- S2
- S5
8.s4 - S2
10.s1 but anterior lateral is l5 - S2 but anterior medial is l4
Landmark,Dermatome
Suprasternal notch,T2–T3
Nipple,T4
Xiphoid process,T6
Umbilicus,T10
Inguinal region,L1
