Soft Tissue

Question 1

What are the four types of tissue ?

Answer 1

Connective tissue - fills internal spaces, structural support, transports materials and stores energy

Epithelial tissue - covers exposed surfaces, lines internal passage ways and forms glands

Muscle tissue - specialised for contraction - skeletal,cardiac and muscular walls of hollow organs

Nervous/neural tissue - transports info in form of electrical impulses eg brain, spinal cord and peripheral nerves.

Question 2

Epithelial tissue
Brief description -

Answer 2

Includes epithelia and glands
Epithelia are cells that cover internal or external surfaces
Glands produce fluid secretions and are either attached to/derived from epithelia
Cells bound closely together
Epithelia is avascular ( lack blood vessels ) therefore obtain nutrients by diffusion or absorption
Cells are continuously replaced/regenerating

Question 3

Epithelial tissue function
Physical protection -
Permeability -

Answer 3

Physical protection - protects exposed / internal surfaces from abrasion, dehydration and destruction by chemical / biological agents

Permeability - any substance entering / leaving the body must cross an epithelium variable permeability - some easy / hard.
Eg skin - low permeability ( most forgein substances cannot get through)
Digestive tract - selective, allows absorption of good nutrients and rejects harmful substances

Question 4

Epithelial tissue function
Provide sensation -
Produce specialised secretions -

Answer 4

Provide sensation - large sensory nerve supply eg touch something hot
Continually providing info about internal / external environment
Smell, taste, sight, equilibrium, hearing

Specialised secretions - secretions produced by glands
Secretions either discharged onto surface of epithelia or released into interstitial fluid/blood.
Eg sweat, mucus, hormones

Question 5

Brief structure of epithelial cells -

Answer 5

Basal surface at base - either attaches to other cells or deeper tissue. Mitochondria and nucleus sit above
Top cell - microvilli therefore increased SA x20 therefore efficient absorption and secretion. Some have cilia as well to help move substances over the surface. Eg respiratory tract have cilia.

Question 6

Classification of epithelial tissue
Number of layers -
Cell shape -

Answer 6

Number of layers - simple ( one layer )
Stratified ( multiple layers )

Cell shape - squamous ( flat )
Cuboidal
Columnar

• areas that are likely to sustain more damage eg skin or mouth are likely to be stratified therefore have multiple layers.

Question 7

Epithelial tissue
Glands - endocrine -

Answer 7

Ductless gland
Secrete hormones into cellular spaces and then into blood
Hormones regulate or co-ordinate activities of various tissues, organs and organ systems
Eg pituitary, thyroid, thymus
Thyroid - produce metabolism regulatory hormones

Question 8

Epithelial tissue
Glands - exocrine -

Answer 8

Secrete products into ducts that empty on to the epithelial surface
Eg digestive enzymes, sweat, tears

Question 9

Connective tissue
Brief description -

Answer 9

Diverse group of supporting tissues
Vary widely in appearance and function
Never exposed to outside environment
Connect the epithelial tissue to the rest of the body
Many are highly vascular
Fill internal spaces

Question 10

Classification of connective tissue ( CT )
CT proper - loose CT:
Adipose:

Answer 10

Loose CT: ( ariola tissue ) made up of loosely packed collagen and elastin fibres - found throughout the body
Fills spaces around organs
Elastin fibres make it resilient ( will return to original shape )

Adipose: sometimes classed as its own type of CT or can be grouped with loose CT. Similar structure to loose, but a much higher proportion of fat cells
Function - provides padding, absorbs shocks, insulates body and stores energy.

Question 11

Classification of connective tissue ( CT )
CT proper - dense CT:

Answer 11

Dense CT: ( fibrous CT )
Dense, regular - made up of collagen fibres, densely packed and running parallel to eachother eg tendons / ligaments
Dense, irregular - fibres more interwoven. Form a mesh therefore tissue can be subject to stress from different directions. Eg present in dermis ( deep layer of skin )

Question 12

Classification of connective tissue ( CT )
Fluid CT - blood and lymph:

Supporting CT - cartilage:
Bone:

Answer 12

Blood and lymph - fluid CT. Transports cells and dissolve materials around the body

Cartilage - supporting CT. Found in joints - particularly articular surfaces. Protects the bone and plays role in shock absorption - reduces friction. Densely packed collagen fibres allow it to withstand compression.

Bone - supporting CT. Provides support and movement and protects organs. Mineral deposits - mainly calcium.

Question 13

Functions of connective tissue -

Answer 13

Establishes bodies structural framework - bone and loose CT
Transports fluids and dissolved materials - blood and lymphatic system
Protects delicate organs - bone and loose CT
Stores energy ( triglycerides ) - adipose tissue
Helps to defend body from invading micro-organisms - blood, lymph

Question 14

Connective tissue
Cartilage -
Name the three types -

Answer 14

Cartilage is closely packed collagen fibres embedded in a firm matrix gel containing chondrocytes and proteoglycans
Chondrocytes - cells within cartilage. Produce and maintain cartilage matrix
Proteoglycans - compound - protein and sugar. Regulate movement of molecules in and out of matrix

Cartilage is avascular therefore absorbs all nutrients via the matrix and doesn’t heal well.
Types - hyaline, elastic and fibrocartilage.

Question 15

Connective tissue
Hyaline cartilage -

Answer 15

Most common type
Closely packed collagen fibres in matrix
Tough but flexible
Found- in most joints covering articular surfaces eg acetabulum and femoral head of ball and socket joint in hip
Between ribs and sternum
Nasal cartilage
Supporting cartilage in respiratory tract

Question 16

Connective tissue
Elastic cartilage -

Answer 16

Numerous elastic fibres therefore resilient but flexible
Found - external flap ( auricle ) of the ear
Epiglottis, in throat, prevents food and liquid entering the lungs
Auditory tube
Small cartilages in larynx

Question 17

Connective tissue
Fibrocartilage -

Answer 17

Densely packed interwoven collagen fibres therefore extremely durable and tough
Resists compression and absorbs shock
Found - between vertebrae
Between pubic bone
Meniscus

Question 18

Membranes
Brief info and the different types:

Answer 18

Membranes occur when epithelial tissue and connective tissue is combined.
Consists of epithelium supported by connective tissue
Four types of tissue membranes:
Mucous membranes
Serous membranes
Cutaneous membranes
Synovial membranes

Question 19

Membranes
Mucous membranes -

Answer 19

Line passageways that open to exterior eg digestive, respiratory, urinary and reproductive tracts. Epithelial surfaces kept moist to reduce friction and facilitate absorption/secretion.
Thin layer of epithelial cells therefore often simple classification.

Question 20

Membranes
Serous membranes and the three types -

Answer 20

Line sealed, internal subdivisions of the body cavities
Not open to exterior
Very thin and transparent
Firmly attached to body wall and organs that they cover
Minimise friction - serous fluid production to achieve this. Injuries can make serous fluid increase.
3 types of membrane -
1) Pleura - lines pleural cavity and covers lungs. PLEURISY, when pleura becomes inflammed, causes sharp pain when breathing.
2) peritoneum - lines peritoneal cavity ( abdominal ), covers surface of exposed organs. PERITONITIS, when it gets inflammed.
3) pericardium - lines pericardial cavity, covers heart. PERICARDITIS, inflammation.

Question 21

Membranes
Synovial membranes -

Answer 21

Around joint cavity - forms synovial capsule. Made up of CT with a layer of macrophages and fibroblasts. Synovial fluid in capsule - lubricates and nourishes the hyaline cartilage joint movement stimulates formation and circulation of synovial fluid.
Injury/irritation can result in excess fluid production.

Question 22

Membranes
Cutaneous membranes -

Answer 22

Cutaneous membranes ( skin ) - largest organ
Two layers - epidermis ( epithelial tissue )
Dermis ( connective tissue )
Subcutaneous layer of loose connective tissue. Accessory structures - eg hair folicals and glands
Functions - protect underlying tissue
Excretion - slat,water and waste
Temp maintenance
Production of melanin/keratin
Lipids storage ( adipose tissue )
Sensation
Co-ordination of immune response to pathogens/cancers in the skin

Question 23

Ligaments injuries -

Answer 23

Fibrous bands of CT that span joints to connect articulating bones and function stabilise and support the bodies joints. Stretch/tear to ligament can result in injury .
Injury = sprain.

Question 24

Grades of ligament injuries -

Answer 24

Grade I - micro tears. Localised pain/tenderness
No visible bruising, minimal swelling/loss of function
No loss of strength/ROM

Grade II - partial tear. Moderate swelling and bruising
Poorly localised pain
Painful ROM ( with deficit )
Reduced strength and pain on contraction

Grade III - complete tear/rupture. Audible pop and acute pain
Considerable swelling or bleeding
Inability to contract muscle, separation may be evident.

Question 25

Factors that cause tissue damage Injury - Infection - Infarction - Immune reactions -

Answer 25

Injury - physical/thermal/electrical/chemical Infection - viruses/bacteria/fungi/protozoa Wound post surgery for example Infarction - ( blood clot ) myocardial infarct Immune reactions - foreign protein hypersensitivity Auto immunity

Question 26

Types of body tissues Parenchymal tissue - Stromal ( interstitial ) tissue -

Answer 26

Parenchymal - functioning cells of organs Eg neuronal ( brain ) tissue, epithelial ( skin ) tissue, cardiac myocyte ( heart ) tissue and thepatocyte ( liver ) tissue. Stromal - supporting connective tissues, contains many cell types including fibroblasts. Blood vessels Nerves/nerve endings

Question 27

Types of tissue healing 1) resolution -

Answer 27

Rapid healing of mild injury. Epithelial cells regenerate without incident. Occurs in acute inflammatory response to minor injuries/those with minimal affect to Parenchymal cell. Tissue is in effect restored to the state it was before injury occurred. Commonly occurs in epithelial tissue eg mild insect bite to skin.

Question 28

Types of tissue healing 2) tissue regeneration -

Answer 28

Replacement of lost Parenchymal cells by division of adjacent surviving Parenchymal cells therefore injured tissue can be restored. This occurring depends on the damaged tissues and cells releasing growth factors to increase mitosis s well as the Regenerative capacity for cells involved and the number of surviving cells. Before it can occur the damaged cells must under go necrosis and be removed. Involved acute inflammatory response.

Question 29

Types of tissue healing 2) regeneration, cell types and their regeneration ability -

Answer 29

Labile cells - constant turnover eg skin Stable cells - stop growing once growth stops. Requires supportive framework if damage occurs eg liver, kidney, lung Fixed, non - dividing cells - cannot undergo mitosis, tissue repair leaves a scar. Eg nerve, muscle, cardiac.

Question 30

Types of tissue healing 3) connective tissue repair - 1st and 2nd phase -

Answer 30

4 phases, these phases will overlap. Healing time will vary depending on extent of damage. 1) bleeding phase - following injury, short lived, more vascular tissue. Eg muscle will bleed for longer. Other tissues eg ligaments bleed less in volume and duration. Average 4-6 hours. 2) inflammation phase - occurs in first few hours of injury. Usually 1-3 days. Resolve in a few weeks. Changes in bloodlfow - oedema. Leukocyte emigration Phagocytosis Lymphatic drainage

Question 31

Types of tissue healing 3) connective tissue repair 3rd and 4th phase -

Answer 31

3) proliferative phase - 24-48 hours after injury. Can last few weeks/months Fibroblasts, macrophages and blood vessels proliferate to form granulation tissue ( scar ) Two crucial processes associated - angiogenesis - formation of new blood vessels, and collagen synthesis - produce type III collagen fibres for scar tissue structure. 4) remodelling/maturation phase - begins 3 weeks and can last up to 2 years. Continuous remodelling of scar tissue Collagen ( type 1 ) synthesis by fibroblasts Simultaneous lysis by collagenase enzymes Physical stress is important influencing factor.

Question 32

Healing Primary intention -

Answer 32

Wound edges joined by fibrin plug. Regrowth of basal layer of epidermis. Lysis of fibrin and re-epithelialisation. Restoration to intact skin. Edges of wound are in close opposition therefore can heal by primary intention.

Question 33

Healing Secondary intention -

Answer 33

Large defect filed by fibrin clot. New blood vessels and fibroblasts ( granulation tissue ) grow from the dermis into fibrin. Collagen laid down by granulation tissue fibroblasts to restore integrity. Maturation of collagen achieves structural integrity and allows epidermis re growth. More extensive damage therefore takes longer.

Question 34

Factors that affect wound healing -

Answer 34

Nature of injury Injury site Temp Movement and stress - too much and too little will both negatively impact healing Malnutrition Bloodlfow and o2 delivery Infection Age

Question 35

Complications of tissue repair -

Answer 35

Infection - invasion of microorganisms Ulceration - circumscribed, open lesions of the skin or mucous membranes Dehiscence - deficient scar formation, wound separates Keloid dev - excessive collagen production Adhesions - fibrous connections between cavities and tissues

Question 36

Why are there differences in opinion on the use of ice for tissue healing and repair?

Answer 36

At face value it helps the pain at the injured site. However, there is no evidence to say that clinically there are any benefits.

Question 37

Scenarios - 24 year old prof football player. Damaged medial collateral ligament due to twisting her knee. Explain the clinical signs that may indicate the grade of ligament injury:

Answer 37

Vision - degree of swelling/bruising/redness Whether there was an audible pop - this would indicate a complete tear/rupture Painful to touch/walk on ROM at the area

Question 38

Scenario - 30 year old tennis player injured hyaline cartilage of right knee when twisting it 3 weeks ago. 1) hyaline cartilage structure and how it assists with function - 2) factors that would affect the healing of this tissue:

Answer 38

1) closely packed collagen fibres in a firm gel matrix - tough but flexible Therefore allows movement at joint with reduced friction Avascular 2) constant movement therefore aggravates Medications - long term steroids affect immune system Infection Age - tissue healing decreases with age Diet - pro inflammatory diet reduces healing Sedentary behaviour and infarction (lack of O2)

Question 39

Scenario - 76 year old man involved in house fire. 3rd degree burns to 25% of his body - mostly to hands,arms and face 1) function and structure of skin and how it assists - 2) possible clinical complications now the skin has been damaged -

Answer 39

1) increased age therefore means less collagen and elastin. Epidermis thins Loose facial structure Increased healing time Wrinkling on skin as scar tissue forms 2) increase risk of infection - epidermis more permeable Increased risk of tears to skin Keloid development Adhesions

Question 40

What does PEACE and LOVE stand for ?

Answer 40

Protection - avoid activities and movement that increase pain Elevation - elevate injured limb Avoid anti-inflammatories - reduce tissue healing Compression - bandage/taping Education Load - listen to body as to when to increase load Optimism - confident and positive Vascularisation - choose pain free cardiovascular exercise to increase blood flow Exercise - restore mobility

Question 41

What does POLICE stand for ?

Answer 41

Protect - rest/consider using support eg splint Optimal Loading - active sooner rather than later. Gradual increase. Ice - cold compress to site Compression - bandage to reduce swelling Elevate - injured site elevated above heart