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Flashcards in Movement Deck (347):
1

Functions of the skeletal system (5)

- support
- movement
- protection
- storage
- RBC formation

2

Two types of bone tissue

- compact
- cancellous

3

Where is compact bone found?

Where strength and load bearing is needed

4

Where is cancellous bone found?

Where shock absorption is required.

5

Bone classes

Long bones
Short bones
Flat bones
Irregular bones

6

Describe long bones

- longer than they are wide
- shaft or diaphysis
- extremities or epiphyses
- function as levers for movement
- thicker compact bone in diaphysis

7

Function of long bone

- function as levers for movement

8

Describe short bones

Near equal in with and length
- weightbearing/shock absorption
- mostly cancellous bone.

9

Function of short bones

- Weightbearing/shock absorption.

10

Describe flat bones

- thin plates of compact bone - some cancellous (eg ridges for muscle attachment)

11

Function of flat bones

- Protection - cranial bones
- muscle attachment - scapula

12

Describe irregular bones

Variable shape and function

eg vertebrae

13

2 Divisions of the skeleton

1. Axial
2. Appendicular

14

Bones of the axial skeleton

- Skull
- Vertebral column
- Rib cage

15

Bones of the skull

- cranium (cranial vault)
- facial bones
- mandible

16

Bones of the vertebral column

- cervical (7)
- thoracic (12)
- lumbar (5)
- sacrum (5 fused) and coccyx (2-5 fused)

17

Bones of the rib cage

- ribs
- sternum

18

Bones of appendicular skeleton

- limbs
- regions: arm, forearm, thigh, leg

19

Main function of lower limb

Stability and locomotion (bipedal)

20

Main function of upper limb

Manipulation and mobility

21

Structure of limbs

- single proximal long bone
- two distal long bones
- hands and feet

22

2 limb attachment points

- pectoral (shoulder) girdle
- pelvic girdle

23

Bones of pectoral girdle

- clavicle
- scapula

24

Bones of pelvic girdle

- hip bones (2)
- sacrum (axial)
= pelvis

25

Function of pectoral girdle

For motility

26

Function of pelvic girdle

For stability

27

What is the pelvic girdle designed for

Limited movement for stability due to incoming forces from above.
- cope with locomotion.

28

Structure of hand

8 carpals
5 metacarpals
5 x 3 phalanges (2 phalanges in thumb)

29

What is the hand designed for

Manipulation and fine movements

30

Structure of the foot

7 tarsals
5 metatarsals
5 x 3 phalanges (2 in big toe)

31

What is the fit designed for

- weight transfer
- stability
- elongated lever for assisting with locomotion.

32

Two bones of ankle joint

Articulation between tibia and talus.

33

Properties of Bone Tissue

- bone has cells
- bone grows
- bone remodels
- bone can repair itself

34

What type of tissue is bone tissue

Connective tissue

35

What are the two extracellular components of bone tissue

- organic
- inorganic

36

How much of bone tissue is organic?

33%

37

How much of bone tissue is inorganic?

67%

38

What are the organic components of bone tissue

- collagen (protein) (in fibers)
- ground substance (proteoglycans)

39

What is the function of organic component of bone tissue

Resist tension

40

What happens to bone if there isn't the organic component

If collagen is removed -> brittle/breaks easily

41

What is the inorganic component of bone tissue composed of

- hydroxyapatite (mineral salts)

42

What is the function of inorganic component of bone

- resist compression (due to hardness) as one of the function of the bone is to support.

43

What happens if the inorganic of bone is removed

Mineral removed -> bone too flexible

44

What are the cellular components of bone

- Osteoblasts
- Osteocytes
- Osteoclasts

45

Function of OB

Build ECM

46

Function of Ocytes

Mature bone cells (for communication in remodelling process)

47

Function of OC

Break down ECM
- multinucleated

48

Similarities in composition of compact and cancellous bone

Made of same material but organised in different was microscopically.

49

Compact bone at a gross level

- outer surfaces seem impenetrable
- foramina/holes (towards ends)

50

Function of foramen in bone

Provide nutrient to cells trapped at compact level to maintain cells

51

Structures in compact bone at a microscopic level

- osteon
- lamellae
- central canal
- lacunae
- canaliculi

52

Describe osteon

Longitudinal cylinder within compact bone.
- lamellae form a series of cylinders running longitudinally down shaft = osteon

53

Describe lamellae

Tubes of ECM with collagen fibres aligned to resist forces

54

Function of osteon

Maintain OC by providing nutrients

55

Function of lamella

Form a series of cylinders running longitudinally down shaft = osteon.

56

Describe central canal

Blood vessel and nerves

57

Describe lacunae

Lakes for Ocytes

58

Describe canaliculi

Channels for Ocytes thru ECM

59

Arrangement of collagen fibres in lamellae

Fibres in different directions to resist tensile forces

60

Describe periosteum

Fibrous connective tissue sheath around bone

61

Describe subperiosteal surface of bone

Surface of the bone where blood vessels penetrate

62

Describe the remodelling process

- Osteoclastic front: osteoclasts come in through and destroy ECM, resulting in a void
- osteoblasts come and build ECM

63

Structure of cancellous bone

- trabeculae -> struts of lamellae bone
- marrow fills the cavities
- osteocytes housed in lacuna on surfaces of trabeculae

64

Function of cancellous bone

- resist compressive forces and shock absorption
- trabeculae in areas for shock absorption
- aligned in certain ways to diffuse forces

65

Describe the zone of weakness

Forces coming from superior = strengthening on inferior part of neck to try to resist those forces.
- leaves area with less trabeculae to provide strength -> zone of weakness.

66

Describe the path of force from upper body to hip

Come from above, through sacrum, then joint between sacrum and pelvis, then hip bone, then neck of femur, then down shaft.

67

What is ossification

The process of transforming cartilage to bone

68

What does bone begin as

A cartilage model

69

Where is the primary centre of ossification

Diaphysis or shaft

70

Where is the secondary centre of ossification

Epiphysis

71

What are growth plates/epiphyseal plates made of

Cartilage

72

What is the process of bone formation

- cartilage cells transformed into bone (bone formation spreading essentially from the centre to the ends) and destroyed by osteoblasts
- the cartilage model then develops a periosteum that soon enlarges and produces a ring, or collar, of bone.
- bone is deposited by OB, which differentiate from cells on the inner surface of the covering periosteum/
- Soon after the appearance of the ring of bone, the cartilage begins to calcify, and a primary ossification centre forms when a blood vessel enters the the rapidly changing cartilage model at the midpoint of the diaphysis
- endochondreal ossification progresses from the diaphysis toward each epiphysis, and the bone grows in length -> INTERSTITIAL GROWTH
- secondary ossification enters appear in the epiphyses, and bone growth proceeds toward the diaphysis from each end.
- bone tissue formed at bottom of growth plate
- until bone growth in length is complete, epiphyseal plate remains between each epiphysis and the diaphysis
- during periods of growth, proliferation of epiphyseal cartilage cells brings about a thickening of this layer.
- Ossification of the additional cartilage nearest the diaphysis follows - that is, osteoblasts synthesise organic bone matrix, and the matrix undergoes calcification.
As a result, the bone becomes longer.
- it is the epiphyseal plate that allows the diaphysis of a long bone to inc in length.

73

How does the epiphyseal plate allow growth in length

= layer of cartilage between epiphysis and diaphysis

- during periods of growth, proliferation of epiphyseal cartilage cells brings about a thickening of this layer
- ossification of the additional cartilage nearest the diaphysis follows - OB synthesis organic bone matrix, and the matrix undergoes calcification
- as a result, the bone becomes longer.

74

4 layers of cells of epiphyseal plates

- top layer closest to the epiphysis composed of "resting" cartilage cells. These cells are not proliferating or undergoing change. This layer serves as a point of attachment firmly joining the epiphysis of a bone to the shaft.
- Proliferating zone. Composed to cartilage cells that are undergoing active mitosis. As a result of mitotic division and increased cellular activity, the layer thickens and the plate as a whole increases in length.
- zone of hypertrophy is composed of older, enlarged cells that are undergoing degenerative changes associated with calcium deposition.
- layer closest to diaphysis = thin layer composed of dead or dying cartilage cells undergoing rapid calcification. As the process of calcification progresses, this layer becomes fragile and disintegrates. The resulting space is soon filled with new bone tissue, and the bone as a whole grows in length.

75

How do bones get wider

OB in periosteum
- OB lay down new bone on outside of shaft

76

How do bones get moulded into shape

OC from endosteum mould the bone shape and form the medullary cavity

77

What is bone pathology

An imbalance of OC or OB activity

78

What is Osteoporosis

When OC's overtake OB's

79

What is a symptom of osteoporosis in compact bone

Compact bone becomes thinner and porous

80

What is a symptom of osteoporosis in cancellous bone

Loss of volume
- compression fractures of vertebrae

81

Causes of osteoporosis

- ageing-loss of oestrogen
- lifestyle factors:
- lack of exercise: exercises stimulates normal bone remodelling process
- nutritional factors: diet high in Ca2+ is important
- peak bone mass - bone as a bank: reach peak bone mass in 20's, must maintain.

82

Components in Stage 1 of fractures

- haematoma -> blood clot
- capillaries -> capillaries invade site and bring phagocytes
- phagocytes -> clean up debris (broken bone, soft tissue)

83

Components in stage 2 of fractures

- fibroblasts -> formation of soft callus
- chondroblasts (from differentiation of fibroblasts) -> form a pro callous made of cartilage = biological splinting
- chondro = cartilage
- fibrocartilaginous callus (procallus)

84

Components of stage 3 of fractures

- bony callus -> OB invade cartilaginous callus and turn it into bone
- osteoblasts
- ends are now held together by bone

85

Components of stage 4 of fractures

- remodelling
- bone callus disorganised ("new bone").
- remodelled osteoblasts network of nature bone
- remodel so the can't see callus at all in children but in adults can see callus.

86

How long does it take for bony callus to form in child

6 weeks

87

What is pseudoarthrosis

False joint
- due to no fixation of ends of bones
- ends of bones continue to move on each other

88

3 types of fractures

- Closed, simple
- open, compound
- greenstick

89

Describe closed simple fracture

- break in bone but not too much rotation/displacement of bone ends on each other
- minimal soft tissue damage

90

Describe open compound

- displacement of bone ends -> lots of space between bone ends
- bone may penetrate skin
- lots of soft tissue damage (muscles, nerves)
- if bone actually goes out of skin -> prone to infection

91

Describe green stick fracture

- not a complete fracture (whereas there is complete discontinuation in closed and open)
- more common in children (as their bone is not as mineralised as still growing)

92

What is an articulation

Where bones meet

93

What is a joint?

- hold bones together
- involves bone shapes and soft tissues
- allow free movement or control movement

94

What are the soft tissues made of

- Have no inorganic component
- cartilage: hyaline and fibrocartilage

95

Examples of structures made of hyaline cartilage

- nose
- not between sternum and ribs
- cartilaginous model

96

Describe general cartilage composition

- collagen fibres in a ground substance (for resisting tension)
- chondrocytes live in lacuna
- nutrients diffused through matrix by joint loading - not vascular

97

Why is cartilage made of collagen fibres

For resisting tension

98

Describe the structure of hyaline cartilage

- collagen fibres barely visible
- high water content in matrix

99

Function of hyaline cartilage

- resist compression
- provide smooth frictionless surface

100

Structure of fibrocartilage

- collagen fibres form bundles throughout matrix
- orientation of fibres aligns with stresses

101

Function of fibrocartilage

Resist compression AND tension

102

Function of hyaline cartilage in joints

- to provide frictionless movement of bones in synovial joints
- moulds to surfaces of the bones where they articulate

103

How can hyaline cartilage degrade

- with age
- trauma

104

Function of fibrocartilage

- concave discs of fibrocartilage
- deepens articulation at knee
- can adapt its shape to stresses on joint in movement

105

eg of fibrocartilage

- meniscus at knee joint
- between vertebral bodies.

106

What is bony congruence

the sum of the bone surfaces that form an articulation

107

Relationship between bony congruence and amount of soft tissue support

Less BC = more soft tissue support

108

What are ligaments and tendons made of

- DFCT
- collagen
- fibroblasts(cytes)

109

Function of ligaments and tendons

Resist tension

110

Are ligaments and tendons vascularised

Some vascularity but minimal compared to bone.
- very slow healing.

111

Which structures do ligaments join

- bone to bone

112

Function of ligaments

- restrict movement
- movement is restricted "away from itself"
eg lateral restricts adduction
eg medial restricts abduction

113

Which direction is movement restricted form in ligaments?

Away from itself.

114

Which structures do tendons join

- muscle to bone
- inserts into bone
- muscle shortens, pull on tendon = pull on bone = produce movement.

115

Function of tendons

- facilitates and controls movement
- contraction

116

How is ligament inserted

- fibres insert into bone tissue
- zone of calcification where ligament turns into bone

117

How are tendons inserted

- muscle merges with periosteum first and then into bone tissue.
- area of mineralisation between bone and muscle

118

3 types of joints

- fibrous joints
- cartilaginous joints
- synovial joints

119

What are fibrous joints made of

Tisse = DFCT

120

What is the difference between tissue and structure

Tissue is the material that makes up structure eg ligament

121

What is the structure of fibrous joints

Ligament

122

Function of fibrous joints

Limited movement. For stability.
- find where greater stability is required. Don't want bones to move

123

Where is the ligament in fibrous joints

Directly between 2 bones and articulates and joints them together.

124

Examples of fibrous joints

- Cranial sutures: stitch-like, short joints between bones of cranial vault.
- main function is to protect brain and therefore don't want cranial bones to move.
- in between bones are short, strong joints made of DFCT


- in distal tibiofibula joint
- cements bones together with DFCT
- weight thru body and ankle, and therefore don't want to move apart: inefficient and vulnerable to injury

eg between root of teeth and jawbone

125

What are cartilaginous joints made of

Tissue = fibrocartialge

126

How much movement do cartilaginous joints allow

Some allowed and required

127

Function of cartilaginous joints

- fibrocartilage resists compression and tension
- find in parts of body where there are compressive forces and some movement between bones
- special functions and various structures

128

Another name for Fibrous joints

Synarthroses

129

Another name for cartilaginous joints

Amphiarthroses

130

Another name for Synovial joints

Diarthroses

131

Examples of cartilaginous joints

eg intervertebral disc: joint between vertebral bodies
- nucleus pulposis that rolls around as we move
- disc is attached to bone by a ligament


eg pubic symphysis: joint between 2 pubic bones in pelvis
- anterior joint of pelvis girdle
- in between 2 bones -> disc of fibrocartilage -> cartilaginous joint
- some movement allowed for both M and F as all of the forces are going through the posterior part of the pelvic girdle.
- forces through torso, joints between sacrum and pelvic
- need stability
- but forces still go through the anterior art of the pelvic girdle
- if had fibrous joint joint, which does not allow ANY movement, any diffusion of forces -> vulnerable to injury.
- for females, in 3rd trimester. Hormonal release: relax joint and opens up during childbirth slightly.

132

How much movement do synovial joints allow

- free-moving
- in most joints of the limbs except eg distal tibiofibula joint
- to allow free movement/locomotion and manipulation

133

What is the function of synovial joints

to allow locomotion
- facilitation of free movement (of bones over each other as we move)
AND
- control of movement where we want to restrict some movement

134

General structure of synovial joints

Complex association of tissues and structures
- all of the different tissues present in some way
- cartilage: hyaline and fibrous
- DFCT

135

What determines the range of movement possible at a joint

Bone end shape

136

Describe the femoral head and the range of motion it allows

- round projecting head of femur
- completely encased in socket of pelvic bone
- allows all types of movement: angular and rotation
- deep articulation = high bony congruence and therefore is stable
- less soft tissue support of the knee is required due to high bony congruence

137

Describe the femoral condyles and the range of motion it allows

Articulation from femural condyles onto flat surface of tibia
- meniscus (made of fibrocartilage) deep articulation and help with accomodating lack of bony congruence and deepening articulation to increase stability
- lot of soft tissue support outside around and inside too.

138

Where is articular cartilage found

covers bone ends where they articulate AND move over each other.

139

Is subchondral bone smooth

Yes. (under articular cartilage)
- outside has foramen
- roughened where ligaments and muscles attach

140

Why do condyles project at the back

to allow full flexion and extension
- at the back there is smooth bone covered in articular cartilage

141

What are the two types of ligaments

Capsular and intracapsular

142

Describe capsular ligaments

- primary ligament
- like a sleeve

- holds bones together: articulates and joints 2 bones together
- tight & thick wire more support is required
- loose on sides where movement is allowed -> loose and thin at a more mobile joint.
- eg in shoulder joint -> very loose and thin joint capsule & therefor support must come form other structures (aka muscles in shoulder)
- eg knee: thick on lateral and medial but loose and thin on posterior and anterior
- potential space/cavity allows movement over each other.
- synovial membrane lines the inner surface of the capsule
- secretes synovial fluid -> lubrication of joint

143

Describe the structure of synovial joint

- joint capsule (goes from one bone, around bone ends to insert into other bone)
- synovial membrane lies the joint capsule
- articular cartilage around bone ends
- cavity/potential space
- synovial fluid (helps with movement in potential space). Lubricates joint
- there may be fibrocartilage which deepen articulation, like meniscus
- muscles around helps hold femural head.

144

Describe structure of capsular ligament

- thickening of capsule where more support is required

145

Draw a labelled diagram of a synovial joint

.

146

Describe the collateral ligaments of the knee

- medial restricts abduction
- lateral restricts adduction

- a ligament restrict movement away from itself

147

Function of intracapsular ligaments

- restricts movement between bones
eg knee: specifically stop femur from moving anteriorly or posteriors on the tibia.


- when walking, tibia wants to move from side to side.
- collateral ligaments placed medially and literally to stop adduction and abduction.
- therefore only flexion/extension are allowed.

148

Are intracapsular ligaments part of the capsule

No. It's inside the capsule

149

Where is the origin of intracapsular ligaments

Arise (originate) from tibia and insert into femur.
- cross over each other in knee

150

How are the intracapsular ligaments in the knee arranged?

- Anterior cruciate crosses posterior and insert into posterior parts
- Posterior cruciate ligament inserts into anterior part of femur between two condyles

151

how do the cruciate ligaments restrict movement of femur?

- Anterior cruciate restricts posterior displacement of femur
- posterior cruciate restricts anterior displacement of femur.

152

Why are cruciate ligaments important for going up stairs, down/up steep slope etc

Femur wants to slide posteriorly off femur going up
Femur wants to slide anteriorly off femur going down

153

How is the intracapsular ligaments usually damaged

From external forces -> fixation of tibia but rest of body keep moving.

154

What are menisci made of

Fibrocartilage

155

What is the fibrocartilaginous menisci important for

Deepening articulation between femur and tibia, and diffusing compressive forces.

156

Main difference between fibrous and cartilaginous joints, and synovial joints

- in fibrous and cartilaginous joints, tissue forming structures inside between bones -> glue bones together to either: stop movement entirely, or allow some movement


- in synovial joints, the joint capsule goes from one bone to another bone and leaves those bone ends free to move over each other.
- dependent on how much movement is allowed and where it needs to be restricted depends on where it is around the joint.

157

What are bursae in the knee

Small sacs filled with synovial fluid, which act to protect the structures inside the knee, reducing friction as they slide over each other when the joint is moving.

158

What is a fibrous joint made of

Two bones are held together with collagen.
- collagen fibres allow little, if any, movement

- no cartilage
- no fluid-filled joint cavity

159

What is a cartilaginous joint made of

The ends of the bones in a cartilaginous joint are covered with a thin layer of hyaline cartilage, with the bones being connected by tough fibrocartilage.
- the whole joint is covered by a fibrous capsule usually.

- do not allow much movement but they can "relax" under pressure, so giving flexibility to structures such as the spinal column

160

What is a synovial joint made of

The bones are covered by hyaline cartilage and separated by a fluid.
- the joint cavity is lined by a synovial membrane and the whole joint is enclosed by a fibrous capsule.

161

Give an example of sesamoid bones

Patella

- irregular, but appear singularly

162

Atlas

C1

163

Axis

C2

164

How to name phalanges

Distal and Proximal and Middle

165

Structure of Osteocytes

- giant
- multinucleic

166

What's another name name for Central canal

Haversian Canal

167

What's another name for transverse canal

Volkmann's Canal

168

What else is damaged in an open fracture

- damaged muscle and nerve damage

eg can see bone through skin = penetrated skin

169

How long does it take for a fracture to heal

6 weeks

170

How many carpals and tarsals

8 and 7

171

What do long bones function as

Levers for movement

172

What do flat bones function as

- protection eg ribs and sternum, cranial bones
- muscle attachment (eg scapula)

173

What do short bones function as

Weight bearing/shock absorption

174

Example of sesamoid bone

Patella

175

What is the organic component of bone used for

- growth, repair, remodelling, support

176

What is the organic component of bone made of

- Collagen
- ground substance of proteins secreted by CT cells.

177

Function of osteoblasts

- bone forming
- make and secret osteoid (organic matrix)
- made by stem cells in the endosteum

178

What is osteoid

Organic matrix

179

Where are OB made

By stem cells in the endosteum

180

Function of OC

- giant, multinucleate
- erode bone minerals, which are reabsorbed into blood
- many mitochondria and lysosomes

181

Where are osteocytes

Embedded in matrix in lacunae

182

What are Ocytes

Mature, non-dividing OB

183

Structure of OC

- many mitochondria and lysosomes

184

Describe the process of endochondral ossification

1. Periosteum develops and enlarges, producing a bone collar
2. Blood vessels penetrate into diaphysis - centre of ossification
3. fibroblasts in blood differentiate into OB and begin to reproduce spongy bone at the primary center
4. Bone formation spreads along the shaft
5. continuous remodelling occurs creating a marrow cavity
6. secondary ossification enters form when capillaries and osteoblasts migrate into the epiphyses, which are soon filled with spongy bone
7. a proliferating epiphyseal plate of hyaline cartilage remains at the metaphysics

185

Describe the epiphyseal plate

- responsible for lengthening of bones
- chondrocytes (Cartilage cells) proliferate
- OB synthesise organic matrix and it calcifies
- when epiphyseal cartilage cells stop dividing and the cartilage completely ossifies, bone growth ends - epiphyseal cartilage disappears.

186

How does growth in bone width occur

Osteoclasts enlarge diameter of medullary cavity
Osteoblasts from periosteum build new bone

187

Describe osteoporosis

- increased bone porosity
- reduced mineral density and mass
- vertebral bodies for example are very susceptible to damage due to high percentage of cancellous bone
- osteoporotic bone is more susceptible to fractures
- more common in menopausal women believed to be due to the decreased production of oestrogen.

188

Process of bone healing

1. blood vessel tears - vascular damage initiates repair process
- hemorrhage and blood pooling forms a hematoma
- granulation tissue forms - made of inflammatory cells, fibroblasts, bone and cartilage forming cells, new capillaries
2. fibroblasts and chondroblasts form cartilaginous tissue (fibrocartilaginous callus)
- procallus (soft callus)
- soft callus with the in growth of granulation tissue
3. Osteoblasts from bony callus - binds broken ends of fracture like a splint. (stability allows healing to proceed)
- hard callus with in growth of cartilage and bone
4. bone remodelling
- hard callus with bone remodelling.

189

Describe hyaline cartilage

- most abundant
- bluish due to high water content of matrix
- matrix of collagen and ground substance (rich in chondroitin sulphate)
- resists compression
- frictionless movement of bones
- degrades with age

190

Which type of cartilage is most abundant?

Hyaline

191

Describe elastic cartilage

- elastic fibers for elasticity
- collegen for tensile strength

192

Examples of elastic cartilage

- external ear
- epiglottis
- eustachian tubes (connect middle ear to nasal cavity)

193

Describe fibrocartilage

- little matrix
- lots of collagen
- fibers align with stresses
- strong, rigid, dense connective tissue
- resists compression and tension

194

Examples of fibrocartilage

- pubic symphysis
- intervertebral discs
- menisci (increase bony congruence).

195

Does fibrocartilage have LITTLE matrix

yes

196

What are fibrous joints made of

DFCT

197

What are fibrous joints

- articulating surfaces fit closely together
- fixed or limited movement
- eg skull sutures (become ossified in older adults)

198

What are cartilaginous joints made of

- hyaline or fibrocartilage

199

Describe cartilaginous joints

limited movement
- eg pubic symphysis - slight movement during childbirth

200

What are synovial joints made of

Articular cartilage

201

Describe synovial joints

- freely movable joints
- most numerous
- most mobile
- most anatomically complex

202

Most numerous type of joint

Synovial

203

What's the ECM made of

Extracellular matrix (ECM)
Solvent (water, ions)
Proteins
Collagen – strength
Elastin – elasticity
Glycoproteins – bind cells to ECM
Fibronectin
Laminin

204

Human Tissue Act, 2008

Bequest: a body donated for study purposes
Informed consent given by the donor
Living spouse/relatives can override deceased person’s wishes
No limit to how long body parts are kept
Body to be treated ethically

205

RMP is dependent on

The concentration of ions on either side of the membrane
The permeability of membranes

206

Role of insulin and glucagon in the blood glucose feedback system

Insulin produced by beta cells -> blood glucose conc dec
Glucagon produced -> blood glucose conc inc

207

C & C Hormonal vs Neuronal Comunication System

Neuronal:
- fast
- specific
- good for rapidly changing conditions
- good for brief responses
- action potential in axons and neurotransmitter release at synapses


Hormonal:
- targeting by expression of specific receptors on target cells
- relatively slow but long lasting
- hormones released into blood
- good for widespread, sustained responses.

208

Determinants of Range of movement

1. shape of articulating bone surfaces
2. ligament, tendon and muscle location and length
3. body surface contact.

209

Structure of a synovial joint (components)

- bone ends
- articular cartilage: dampen mechanical forces. Allows movement over each other
- capsule: a continuation of periosteum where fracture healing takes place. Consist of collagen
- cavity: not a cavity. Filled with synovial fluid.
- synovial membrane: consist of synoviocytes producing synovial fluid -> constant production. Synovial fluid is also reabsorbed by the synoviocytes.
- ligaments: guide motion of joint. ACL and PCL
- intracapsular ligaments: cruciate ligaments
- meniscus: inner and outer on knee. Distribute load in whichever position. Consists of cartilage

210

Bursa

A synovial membrane filled with synovial fluid
- found in shoulder joint

211

Function of bursae

Serves as cushioning
- at surfaces when tendons running through joints

- comparable to joint cavity.
- enclosed structure

212

What is a synovial joint designed for

Movement

213

Recess

Cavities formed by the joint capsule

214

Factors that limit movement

- Ligaments limit range of movement in certain joints
- muscles can also limit
- geometry of bony ends - most important - and cartilage on top

215

What do intracapsular ligaments serve as (2 functions)

- stabilisers
- proprioreceptive function: realised how situated in space. Nerve fibres in ligament of joints and in receptors of the respective joint capsules

216

Shape of condyles

- less inclined at the front
- bending and getting up -> largest forces at posterior
- difference in geometry generate load peaks -> meniscus distribute load evenly.

217

What is movement a balance between

Stability and mobility
- trade off between the 2

218

Compare shoulder and hip joint

hip has lower range of movement as need stability compared to shoulder joint. (for locomotion)
- therefore shoulder joint dislocated more often than hip joint

219

What is range of motion determined by

- bone end shape
- ligament location and length
surface surface contact -> creating a counter force on either side (lots of overlap at femoral head and hip socket compared to shoulder joint: 20% contact as the shoulder joint is designed for mobility.

220

What is the instrument for measuring ROM

Goniometer

221

What is a goniometer

Used for measuring range of movement

222

Different types of synovial joint shapes

- hinge
- pivot
- saddle
- ellipsoid
- condylar
- plane
- ball and socket

223

Uniaxial joints

- hinge
- pivot

224

Biaxial joints

- saddle
- ellipsoid
- condylar

225

Multiaxial joints

- plane
- ball and socket

226

Hinge joint

Uniaxial
- flexion and extension

eg
- ankle
-elbow (jumpers with ulna)
- interphalangeal joints

- refined, guided movement by ligaments on either side and surface of cartilage

227

Pivot joint

Uniaxial
- rotation: supination and pronation

- radioulnar joints
- C1 and C2: atlas and axis. C2 sticks inside C1 -> allows rotation

- ligaments guide movement
- muscle around radius head allows for movement (proximal)

228

Saddle joint

only found in one region
- biaxil
- flexion/extension
- adduction - abduction
- circumduction

Obligatory rotation opposition

eg carpometacarpal joint
base of thumb

provides huge stability

229

Ellipsoid joint

- bixaxial
- flexion/extension (can be done to a larger degree than adduction and abduction)
- adduction/abduction - towards ulna and radius
- circumduction
no rotation (very little rotation)

eg wrist joint

- important for load distribution through ellipsoid joint

230

Condylar joint

Biaxial
- flexion - extension
- rotation

eg knee joint - ligaments -> flexion and extension
- temporomandibular joint

- limited range of motion by ligaments or other structures eg bony ends

231

Which cruciate ligament tenses during extension

Posterior

- during flexion the ACL tenses

232

Plane joint

- sliding and gliding
- flat articular surfaces
- intercarpal
- inter tarsal

- limited movement by dense ligaments
- only works if the surfaces are fairly even and fairly flat.

- surfaces that can glide on top of each other.

233

Ball and Socket joint

- multiaxial
- flexion/extension
- adduction-abduction
- circumduction
- rotation

eg shoulder
hip

Guided by the long tendons of brachii muscle

Intracapsular ligament in shoulder joint also with proprioreceptive function

234

Describe the glenwood cavity joint

Joint surface at scapula much smaller than joint surfaces on the humeral side that allows for huge range of movement
- shoulder joint
- not only guided by ligaments but also by tendons of muscles
-> by long tendon of biceps brachii

235

What guides the movement of shoulder joints along with ligaments

Long tendon of biceps brachii

236

What is muscle designed for

to contract

237

What affects the function of muscle

Arrangement of fibres

238

3 types of muscles

Skeletal - small striated fibres
Smooth - GI system, eye, other viscera
Cardiac - completely different function and metabolism and microstructure. Merging skeletal and smooth functionalities

239

What is the connective tissue that the muscle cells are wrapped in?

Type 1 collagens
- forms sheaths at all magnifications
- useful to create huge forces

240

What collagen form the layers of connective tissue that wrap around muscle cells?

Type 1 collagens

241

Functions of Skeletal muscle (4)

1. Movement
- to any extent
- eg locomotion

2. Heat Production
- body temperature
- freezing -> shivering from skeletal muscles shaking 20-30Hz. Create a huge amount of heat
- 20-30Hz muscle shaking

3. Posture
- maintained by skeletal muscles

4. Communication
- gestures
-body language
- muscles of face: smiling, looking
- key driver of effective communication
- 80% gestural, 20% verbal.

242

Fascia

Collective term for all connective tissue - in muscle and between muscle
- can be extended to tendons

243

What does muscle extend into

Bone.
- which consists of collagen (type I) and hydroxyapatite

244

Endomysium

Single muscle fibre wrapped in

245

Perimysium

Fibre bundles wrapped in
- important for blood: arteries and veins
- region where blood supply travel through

246

Epimysium

wraps muscle all around

247

How long is one muscle fibre

up to 40mm

248

How are muscle fibre arranged

Parallel
Cylindrical
Striated - protein arrangement (repeat arrangement of proteins)

249

Are muscle cells single or multi nuclei

Multinuclear
- cells merged so more than 1 nuclei
- nuclei not in middle of cell
- pushed aside otherwise in way of contractile mechanism

250

2 key proteins in muscle cells

Actin and myosin
- enable muscle contraction -> fibres merged into a composite called sacromere

251

two key metabolites for muscle cells

ATP and Ca2+

252

What are actin and myosin

2 key proteins in muscle cells

253

What are ATP and Ca2+ for muscle cells

key metabolites

254

What is a sarcomere

Actin and myosin merged into one functional composite.
- segment of myofibril between 2 successive Z discs
- each sarcomere function as a contractile unit
- A bands of sarcomeres appear as relatively wide, dark stripes (cross striae) under the microscope, and they alternate with narrower, light-coloured stripes formed by the I bands

255

Components of muscle cells

Myocyte
Myofibril
Myofilaments in sarcomere (thick and thin proteins)
Sarcomere = protein arrangement

256

Length of sarcomere

2 µm

257

How is the sarcoplasmic reticulum specialised

For liberate Ca2+ upon to facilitate muscle contraction

258

How are sarcomeres arranged

end-on-end along myofibril in length
- Z line
- boundaries of sarcomere
- link actin filaments
- composed of myosin and actin
- sarcomere framed by actin
- reaching towards the other side of the sarcomere
- cannot change length
- myosin in middle
- contractile process -> myosin carried into actin ends

259

What is the contractile process of the muscle

Myosin carried into actin ends

260

What do the arms on the myosin do

Under metabolism of ATP to ADP, help muscle fibres to contract
- E dependent mechanism.

261

What is the Z line made by

Connection between sarcomere

262

What is the A line

Whole length of myosin

263

What is the I line

Between the ends of the myosin

264

What happens when muscle shortens

- thin drawn towards each other over thick
- Z lines move closer together (1µm apart)
- oblique to line of pull

265

What does the uni and multipennate arrangement allow

Capable of exerting much larger forces than just arranged longitudinally

266

Important factors for muscle contraction

- actin and mysoin interdigitate (merging with each other)
- actin and myosin retain their length: actin move relative to myosin -> shortening
- process consumes E
- Ca2+ essential

267

What does muscle contraction process consume

Energy

268

What does muscle form determines function. What does it depend on

1. length of muscle fibres - longer = larger lengths. different along different levers.
2. number of muscle fibres -> if really thick -> exert more force eg muscle belly thick
3. arrangement of muscle fibres -> eg pennate manner -> exert more force

269

Which manner of muscle exert more force

Pennate

270

How much can muscle fibres shorten

50% of resting length

271

Where is a large ROM found in

Long muscle fibres: longest in hamstrings and quads

272

1st factor of muscle form

Length of muscle fibres

273

2nd factor of muscle form

number of muscle fibres

274

What is tension directly proportional to

Cross sectional area

275

Where do muscle originate and insert

Originate from site closer to heart (pro)
- insert at distal

276

Relationship between number of fibres, SA and tension

- greater number of fibres = greater SA = greater tension

277

What is pennate

When fibres are oblique to muscle tendon
= more fibres into same space
- oblique to line of pull (uni, bi, multi)

278

2 types of cross sectional areas

- anatomical and physiological

279

Advantage of oblique arrangement

Higher cross sectional areas -> exert higher forces

280

Are relaxed muscles slightly active

Yes

281

How is the activity of relaxed muscle produced

Delivered by certain amount of nerve activity -> heat production 20-30Hz

282

What happens if nerves didn't innervate muscles

Hypotrophic
- even atrophic

283

What is the substance that is released from the synaptic terminal of motor neurone

Acetyl choline
(terminal ends of nerve fibres - release neurotransmitter)

284

What is the effect of ACh

Depolarise muscle cell to the effect that Ca2+ is liberated

285

What happens when Ca2+ is released as a result of ACh depolarising the cell

helps sarcomeres to contract

286

Which substances help sarcomere to contract

Ca2+ and ATP

287

Does muscle tone produce movement

No

288

Properties of muscle tone

- does not produce movement
- keeps muscles firm and healthy
- helps stabilise joints and maintain posture
- keep muscle metabolically active. If immobilised -> hypertrophic -> loss of protein eg after removing cast

289

Importance/function of muscle tone

- Keep muscles firm and healthy
- helps stabilise joints and maintain posture
- keep muscle metabolically active. If immobilised -> hypertrophic -> loss of protein eg after removing cas

290

2 fibre types

Fibre type I
Fibre type II

291

Fibre Type I

high enzyme activity
- aerobic, slow-twitching -> marathon runners

292

Fibre type II

Low enzyme activity
- anaerobic, fast-twitching -> sprinters
- many contractions in a short time

293

Can there be more than one muscle type in a single muscle

Yes
eg both Fibre type 1 and fibre type 2 muscles in a muscle. Can change ratio over time due to training etc

294

Components of the Motor Unit

- myofibril
- myofibril
- myofilaments in sarcomere: composed of thick and thin proteins
- sarcolemma
- T-Tubules
- Sarcoplasmic reticulum

295

Sarcomere

protein arrangement

296

Function of Sarcoplasmic reticulum

Store Ca2+, which allows muscle contraction

297

3 connective tissues around muscle fibres

- Endomysium
- Perimysium
- Epimysium

298

Which is the key structure to allow vascular and nerve supply

Perimysium
- allow for sliding of muscle fascicles relative to each other

299

Which connective tissue of muscle allow for sliding of muscle fascicles relative to each other

Perimysium

300

Where are the nuclei in muscle fibres

Pushed aside
- if in middle, prevents proper contraction
- therefore merged, as a functional unit
- so more than 1 nuclei for each fibre.

301

Key proteins in myofilament

Actin (thin) and thick (myosin) proteins

302

What is the motion of the musculosystem mainly based on

proteins: muscles, tendons, ligaments

303

Which muscle fibre type doesn't contract as often

Fibre type I (high enzyme activity) -> marathon runners

304

What is the fascia

Extension of muscle towards other muscles/structures

- a band or sheet of connective tissue, primarily collagen, beneath the skin that attaches, stabilizes, encloses, and separates muscles and other internal organs.

305

What is muscle function largely driven by

Nerve action

306

Where do axons extend down to

- terminate at proximal insertions
- save protein and make muscle contract as fast as possible

307

Feedback mechanisms of neuromusclar junction

feedback provided by spinal nerve (root ganglion)
- receives feedback of how muscles are situated in space
- proprioreceptor
- signals integrated to tendons and muscles via nerves articulated in spinal root ganglion.

308

Where is the spinal nerve

Slightly outside of spinal cord

309

Route of an excitation

Most nerve cells that generate an excitation sit at the ventral root of spinal cord
- must travel all the way down to the muscle they innervate with axons
- but only go as far as proximal insertion of a muscle begins
- go as proximal as possible
- to increase the velocity of signal transduction and to save material within axons in neurons

310

Where do most nerve cells that generate an excitation sit?

Ventral root of spinal cord

311

Difference between ventral and dorsal root

The ventral roots (anterior roots) allow motor neurons to exit the spinal cord. The dorsal roots (posterior roots) allow sensory neurons to enter the spinal cord.

312

What is a dorsal root ganglion

a cluster of nerve cell bodies (a ganglion) in a dorsal root of a spinal nerve. The dorsal root ganglia contain the cell bodies of sensory neurons

313

Why do the axons terminate as proximal as possible?

To inc velocity of signal transduction and to save material within axons in neurons

314

How can muscle movement be refined

How fast the axons are firing

315

Are axons myelinated

Yes.

316

Motor endplate

the large and complex end formation by which the axon of a motor neuron establishes synaptic contact with a skeletal muscle fiber (cell)

317

How is a stimulus transferred

Electrical -> Chemical -> Electrical

318

Process of sending a stimulus at the axon

- electric simulus via axon being transmitted to chemical at synaptic cleft and then back to electrical at skeletal muscle cells.
- tiny vesicles to release compounds into synaptic cleft -> ACh
- another transmission by polarisation -> muscle contract


- When nerve impulses reach the end of a motor neuron fiber, small vesicles release a neurotransmitter, acetylcholin (Ach), into the synaptic cleft
- Diffusing swiftly across this microscopic gap, acetylcholine molecules contact the sarcolemma of the adjacent muscle fiber.
- There they stimulate acetylcholine receptors and thereby initiate an electrical impulse in the sarcolemma.
- The process of synaptic transmission and induction of an impulse is called excitation

319

What is the neurotransmitter between nerves and skeletal muscle cells (and some smooth)

ACh

320

What is the process of chemical transmission

Diffusion

321

Why have electrical transmission after chemical

Chemical takes a long time, so have electrical transmission on outer surface of axon

322

Why is Ca2+ so important for contraction?

- proteins do not become longer/shorter
- Ca2+ changes the configuration of actin for making protein
- Ca2+ is responsible for the ends of myosin to make movement that allows muscle contractions
- bound within sarcoplasmic reticulum (while muscles not activated and is released upon contraction

323

Why is Ca2+ important for contraction?

Calcium triggers contraction by reaction with regulatory proteins that in the absence of calcium prevent interaction of actin and myosin.

324

Process of muscular contraction

A neural synapse induces an action potential in a muscle cell (fiber) that, in turn, results in calcium ions to be released into the cytosol from the sarcoplasmic reticulum (excitation-contraction coupling) when calcium channels open. Calcium binds to troponin-C to initiate contraction and this will continue until excitation ceases and the molecular calcium pumps in the sarcoplasmic reticulum membrane remove and sequester the calcium.

So the presence of intracellular calcium causes contraction, and its removal allows the muscle to relax.

325

Cellular composition of motor unit

- NMJ
- Sarcolemma
- T-tubules (transport Ca2+, make Ca2+ available for contraction)
- SR
- Ca2+

326

General functions of muscle (plus 2 extra)

- heat production
- posture
- movement
- communication
- cushioning
- protection of vital organs

327

Quadrupedal standing

- broad base of support (low base of support)
- legs flexed at several joints
- energetic expenditure

328

Bipedal standing

- relatively small area of contact with ground
- plantar surface of feet
- energy efficient
- characteristic for very few species

329

What does gravity act as

Act as a agonist or antagonist
- helps to position our body in space
- use gravity as a counterforce eg as a resistance for locomotion.

330

Where is the line of gravity in the sagittal plane

Runs through body
- runs right down in the middle
- redistribute via both hip joint then down to ankles

331

Where is the line of gravity in the coronal plane

- runs through spine
- far behind in the head (type I lever -> keep head lifted)
- spinal column is curved (the line of gravity sometimes run a bit anterior or posteriors to the spine)
- posterior to hip joint
- at the ankle, slightly anterior

332

Hip joint when bipedal standing

- LoG posterior to joint (therefore effect of gravity on the weight of the body tends to extend the hip joints further)
- joint "pushed" into extension
- extension = ligaments are tight = minimal muscle activity needed to hold the joint in extension

333

What is a locked position

Ligaments are tightened

334

Characters of the capsular ligaments of the hip joint

- dense
- do not run straight down
- wrapped around the joint. Curved
- therefore limit the way we externally and internally rotate
- also prevent from falling back by the ligaments being tensed so don't need quad or iliopsoas to contract just when standing.

335

how thick are the capsular ligaments of the hip joint

up to 0.5cm

336

Knee joint when standing

Line of gravity is anterior to knee joint
- when joint locked into position -> line of gravity is close to patella
- slight overextension when standing
- joint "pushed" into extension
- extension = ligaments are tight -> LOCKED = minimal muscle activity needed to hold joint in extension
- PCL really tense when standing -> stable position
- collateral ligaments help to stabilise in extended position too.

337

Ankle joint when standing

Line of gravity is slightly anterior helping it to fall into a dorsal position
- NOT LOCKED because allowing for balance
- plantar flexors of ankle (particularly soleus) are active all the time, providing sufficient tension to withstand the effect of gravity.
- "falls" into dorsal extension
- plantarflexors stabilise
- energy consumed

338

Which joints are not locked when standing?

Ankle

- hip and knee are locked

339

why is the ankle joint not locked when standing

to allow for balance

- lever of the ankle joint to LoG is really long, so only fine movements are necessary for balancing

340

What inserts into calcaneous?

Achilles tendon

341

Which muscle inserts into Achilles tendon

Triceps surae

342

What helps with standing with as little energy as possible

Muscles and ligaments

343

Main features of bipedal standing

- bipedal stance is characteristic to humans
- feet form base of support (plantar surfaces), but insufficient size to provide only balance solution
- bones joints and muscles have special anatomical features to assist balance solution WITH AS LITTLE MUSCLE AND ENERGETIC EFFORT AS NECESSARY
- standing achieved with very little muscular effort - most at ankle joint

344

Characteristics of bipedal (human walking)

- is learnt
- gait is characteristic
- basic pattern is gait cycle
- STANCE phases and SWING phases
- "heel-strike" and "toe-off"

345

What is the stance phase

Foot touches ground and overcome gravity

346

Whats the swing phase

Provide locomotion and move forward.

347

What are the 8 phases

1. initial contact
2. loading response
3. mid stance
4. terminal stance
5. pre-swing
6. initial swing
7. mid swing
8. terminal swing