AUSTRALIAN CATHOLIC UNIVERSITY ACU PHTY208
WEEK 1-6 EXAM /KEY CONCEPT 2025 ALREADY
GRADED A+ (GUARANTEED PASS)
What are the 3 phases of repair for muscle?
1. inflammation
2. proliferation
3. maturation
what occurs in the inflammation phase (muscle)?
- rupture and necrosis of myofibres
- formation of haematoma
- inflammatory cell reaction
what occurs in the proliferation phase (muscle)?
- phagocytosis of necrotised tissue
- regeneration of myofibres and production of connective scar tissue
- revascularisation by ingrowth of capillaries
what occurs in the maturation phase (muscle)?
- maturation of regenerated myofibres
- retraction and reorganisation of scar tissue
what happens initially after a muscle strain/tear?
- ruptured myofibres contract
- hematoma fills gap between myofibre stumps
What occurs at day 2 post muscle strain?
- formation of connective tissue scar by fibroblast
- necrotised part of myofibres removed by macrophages
What occurs at day 3 post muscle strain?
macrophages secrete growth factors that activate satellite cells
,What occurs at day 5 post muscle strain?
- activated satellite cells form myoblast then fuse into myotubes
- connective tissue in the central zone become more dense
What occurs at day 7 post muscle strain?
regenerating muscle cells extend out into scar region
What occurs at day 14 post muscle strain?
regenerating muscle cells close the gap and scar reduces further in size
Definition of epidemiology
The study of the distribution and determinants of health-related states or events in
specified populations and the application of this study to the control of health
problems.
Incidence
(new cases) / (population x timeframe)
Prevalence
(total number with disease) / (population at risk for the disease)
What are 5 positive influences of life expectancy?
• Improving socioeconomic conditions
• Increasing child survival
• Near-eradication of infection diseases
• High standards of living
• Public health campaigns
What are 5 negative influences of life expectancy?
• Tobacco smoking
• Excessive alcohol
• Physical inactivity• Poor nutrition
• Chronic disease and risk factors
Biomedical risk factors that contribute to the risk of developing chronic health
conditions (4)
,1. High blood pressure
2. Dyslipidaemia and triglycerides
3. Impaired glucose tolerance
4. Body weight - overweight and obesity
Behavioural Risk Factors
• Physical inactivity
• Unhealthy diet
Genetic risk factors to disease
Three broad groups of genetic disease/disorders
- Single gene (monogenic) disorders (cystic fibrosis)
- Chromosomal abnormalities (down syndrome)
- Multi-factorial diseases (coronary heart disease, diabetes cancer)
Types of acute injuries (muscle)
contusions and strains/tear
Chronic/Over use muscles injuries
- Focal thickening/fibrosis
- Compartment syndrome
- DOMS
- Cramps
What is a Muscle Contusion
A muscle contusion usually occurs when a muscle is subject to a sudden, heavy
compressive forces (direct blow to muscles)
e.g. corked thigh
characteristic of a muscle contusion?
- Muscle compression cause muscle fibre damage and rupture of micro vessels
- Triggers an acute inflammatory response to remove the damaged tissue and initiating
repair.
- Pain results from accumulating blood exerting pressure on nerve endings
What are the 2 types of haematomas?
intra and intermuscular
, Intramuscular hematoma:
'leakage' of blood within intact muscle fascia results in
increases intramuscular pressure, which may cause acute compartment syndrome
Intermuscular hematoma
develops if fascia surrounding muscle is torn & blood has access to spread into interstitial and
inter fascial spaces
Myositis ossificans
occurs when haematoma calcifies within the muscle. This is due to osteoblast replacing the
fibroblast in healing process
Signs of Myositis ossificans
1. haematoma doesn't improve in expected timeframe
2. ongoing signs of inflammation (night pain)
3. palpable lump
Muscle Strain/Tear
A muscle is strained or torn when some or all of the fibres fail to cope with the demands
placed upon them (excessive tensile force)
- common in 2 joint muscles
- often occurs during deceleration
symptoms of a mild, 1st degree muscle strain
- minor swelling
- minor discomfort
- no/min loss of strength and ROM
-tears of few muscle fibres
symptoms of a mild, 2nd degree muscle strain
- significant swelling
- significant discomfort
- pain on contraction
- loss of strength
- restricted ROM
- tear of significant amount of fibres
WEEK 1-6 EXAM /KEY CONCEPT 2025 ALREADY
GRADED A+ (GUARANTEED PASS)
What are the 3 phases of repair for muscle?
1. inflammation
2. proliferation
3. maturation
what occurs in the inflammation phase (muscle)?
- rupture and necrosis of myofibres
- formation of haematoma
- inflammatory cell reaction
what occurs in the proliferation phase (muscle)?
- phagocytosis of necrotised tissue
- regeneration of myofibres and production of connective scar tissue
- revascularisation by ingrowth of capillaries
what occurs in the maturation phase (muscle)?
- maturation of regenerated myofibres
- retraction and reorganisation of scar tissue
what happens initially after a muscle strain/tear?
- ruptured myofibres contract
- hematoma fills gap between myofibre stumps
What occurs at day 2 post muscle strain?
- formation of connective tissue scar by fibroblast
- necrotised part of myofibres removed by macrophages
What occurs at day 3 post muscle strain?
macrophages secrete growth factors that activate satellite cells
,What occurs at day 5 post muscle strain?
- activated satellite cells form myoblast then fuse into myotubes
- connective tissue in the central zone become more dense
What occurs at day 7 post muscle strain?
regenerating muscle cells extend out into scar region
What occurs at day 14 post muscle strain?
regenerating muscle cells close the gap and scar reduces further in size
Definition of epidemiology
The study of the distribution and determinants of health-related states or events in
specified populations and the application of this study to the control of health
problems.
Incidence
(new cases) / (population x timeframe)
Prevalence
(total number with disease) / (population at risk for the disease)
What are 5 positive influences of life expectancy?
• Improving socioeconomic conditions
• Increasing child survival
• Near-eradication of infection diseases
• High standards of living
• Public health campaigns
What are 5 negative influences of life expectancy?
• Tobacco smoking
• Excessive alcohol
• Physical inactivity• Poor nutrition
• Chronic disease and risk factors
Biomedical risk factors that contribute to the risk of developing chronic health
conditions (4)
,1. High blood pressure
2. Dyslipidaemia and triglycerides
3. Impaired glucose tolerance
4. Body weight - overweight and obesity
Behavioural Risk Factors
• Physical inactivity
• Unhealthy diet
Genetic risk factors to disease
Three broad groups of genetic disease/disorders
- Single gene (monogenic) disorders (cystic fibrosis)
- Chromosomal abnormalities (down syndrome)
- Multi-factorial diseases (coronary heart disease, diabetes cancer)
Types of acute injuries (muscle)
contusions and strains/tear
Chronic/Over use muscles injuries
- Focal thickening/fibrosis
- Compartment syndrome
- DOMS
- Cramps
What is a Muscle Contusion
A muscle contusion usually occurs when a muscle is subject to a sudden, heavy
compressive forces (direct blow to muscles)
e.g. corked thigh
characteristic of a muscle contusion?
- Muscle compression cause muscle fibre damage and rupture of micro vessels
- Triggers an acute inflammatory response to remove the damaged tissue and initiating
repair.
- Pain results from accumulating blood exerting pressure on nerve endings
What are the 2 types of haematomas?
intra and intermuscular
, Intramuscular hematoma:
'leakage' of blood within intact muscle fascia results in
increases intramuscular pressure, which may cause acute compartment syndrome
Intermuscular hematoma
develops if fascia surrounding muscle is torn & blood has access to spread into interstitial and
inter fascial spaces
Myositis ossificans
occurs when haematoma calcifies within the muscle. This is due to osteoblast replacing the
fibroblast in healing process
Signs of Myositis ossificans
1. haematoma doesn't improve in expected timeframe
2. ongoing signs of inflammation (night pain)
3. palpable lump
Muscle Strain/Tear
A muscle is strained or torn when some or all of the fibres fail to cope with the demands
placed upon them (excessive tensile force)
- common in 2 joint muscles
- often occurs during deceleration
symptoms of a mild, 1st degree muscle strain
- minor swelling
- minor discomfort
- no/min loss of strength and ROM
-tears of few muscle fibres
symptoms of a mild, 2nd degree muscle strain
- significant swelling
- significant discomfort
- pain on contraction
- loss of strength
- restricted ROM
- tear of significant amount of fibres
