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Flashcards in Physiology of Joints Deck (105)
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1
Q

What are the 3 main types of joints in the body and give an example of each

A

Synovial (knee)
Fibrous (skull)
Cartilaginous (intervertebral discs)

2
Q

What are the 3 main types of joints in the body and give an example of each

A

Synovial (knee)
Fibrous (skull)
Cartilaginous (intervertebral discs)

3
Q

How are fibrous joints joined?

Describe the range of movement in this joint

A

United by fibrous tissue

They do not allow any movement

4
Q

How are carilaginous joints joined?

A

United by cartilage

Allow limited movement

5
Q

How are the bones of a synovial joint separeated

A

By a cavity containing synovial fluid and united by a fibrus capsule

6
Q

What part of a synovial joint is lined with synovial membrane

A

The inner aspect of fibrous capsule

7
Q

What is the synovial membrane made up of?

A

Vascular connective tissue with capillary entworks and lymphatics

8
Q

What does the synovial membrane contain

A

Synovial cells (fibroblasts) which produce the synovial fluid

9
Q

What are the articular surfaces of bones covered with

A

Cartilage

10
Q

What can synovial joints be classified into and give examples of these

A

Simple (metacarpophalangeal joint) - One pair of articular surfaces

Compound (elbow joint) - more than one pair of articular surfaces

11
Q

What are 3 main extra-articular structures to support synovial joints

A

Ligaments, tendons and bursa

12
Q

What are the physiological fucntions of joints

A

To serve the functional requirements of the MSK system

Structural support and purposeful motion

13
Q

WHat are the 3 main roles of joints during purposeful motion

A

Stress distribution
Confer stability
Joint lubrication

14
Q

How does the synovial fluid confer stability

A

It acts as an adhesive seal that freely permits sliding motion between cartilaginous surfaces

15
Q

How do ligaments confer stability

A

Provide a second major stabilising influence

16
Q

WHat are the 5 functions of synovial fluid

A

Lubrication of the joint
Facilitates joint movements
Helps minimise wear and tear of joints through lubrication
Aids in the nutrition of articular cartilage
Supplies the chondrocytes (cartilage cells) with O2 and nutrients and remove O2 and waste producets

17
Q

WHere is the synovial fluid located?

A

It fills the joint cavity (

18
Q

How does the synovial fluid not become a static pool

A

It is continuously replenished and absorbed by the synovial membrane

19
Q

Describe the viscosity of the synovial fluid

A

It has a high viscosity - due to the presence of hyaluronic acid (mucin)

20
Q

How does te viscosity of the synovial fluid vary

A

With joint movement

21
Q

What also changes during joint movement

A

The elasticity of synovial fluid

22
Q

What is rapid movement associated with

A

Decreased viscosity and increased elasticity

23
Q

What happens to the viscosity and elasticity of a joint in a diseased joint (osteoarthritis)

A

The viscosity and elasticity become defective

24
Q

Describe the appearance of normal synovial fluid

A

Clear and colourless

25
Q

How many WBC are present

A
26
Q

What happens to the WBC count in inflammatory and septic arthritis

A

THe count increases

27
Q

What happens to the appearance of synovial fluid in traumatic synovial tap and in haemorrhagic arthritis

A

It turns red

28
Q

what causes the synovial fluid to appear thin and opaque

A

The very high polymorph count

29
Q

What is the main functions of articular cartilage

A

It provides a low fruction lubricated gliding surface to help revent wear and tear of joints
It distributes contact pressure to subchodral bone

30
Q

What plays a significant role in determining the mechanical properties of cartilage

A

The composition of the cartilage ECM and the interaction between the fluid and sold phase

31
Q

What causes the zones to differ in the structure of articular cartilage

A

Organisation of collagen fibres and relative content of cartilage components

32
Q

What are the 4 zones of articular cartilage

A

Superficial
Middle
Deep
Calcified

33
Q

The articular cartilage is usually what?

A

Hyaline

34
Q

Describe the properties of articular cartilage

A

Elastic and sponge like

Covers the articuar surfaces of bones

35
Q

What is articular cartilage made up of

A

Predominantly water (70%) and collaged (20%) and Proteoglycans (10%)

36
Q

Where is the highest proportion of water in the cartilage

A

Near the articular surface

37
Q

What happens to the cartilage water content with age

A

It decreases with age

38
Q

What is the function of water in cartilage?

A

To maintain the resiliency of the tissue and contribute to the nutrition and lubrication system

39
Q

What does collagen provide in cartilage

A

Tensile stiffness and strength

40
Q

Where is the highest concentration of proteoglycan found in the cartilage

A

In the middle and deep zone

41
Q

WHat is proteoglycan composed of

A

Mainly glycosaminoglycan e.g. chondriotin sulphate

42
Q

What happens to the composition of cartilage proteoglycan with age

A

It changes - chondriotin decreases with age

43
Q

What is proteoglycan responsible for

A

The compressive properties associated with load bearing

44
Q

What synthesises, organises , degrades and maintains the ECM

A

Chondroxytes (cartilage cells)

45
Q

Describe the relationship between the rate of ECM degradation and the rate at which it is replaced

A

The rate of ECM degradation doesnt exceed the rate at which it is replaced

46
Q

What would occur if the rate of ECM degradation were to exceed the rate of its synthesis

A

Joint disease would occur

47
Q

What would occur if the rate of ECM degradation were to exceed the rate of its synthesis

A

Joint disease would occur

48
Q

How are fibrous joints joined?

Describe the range of movement in this joint

A

United by fibrous tissue

They do not allow any movement

49
Q

How are carilaginous joints joined?

A

United by cartilage

Allow limited movement

50
Q

How are the bones of a synovial joint separeated

A

By a cavity containing synovial fluid and united by a fibrus capsule

51
Q

What part of a synovial joint is lined with synovial membrane

A

The inner aspect of fibrous capsule

52
Q

What is the synovial membrane made up of?

A

Vascular connective tissue with capillary entworks and lymphatics

53
Q

What does the synovial membrane contain

A

Synovial cells (fibroblasts) which produce the synovial fluid

54
Q

What are the articular surfaces of bones covered with

A

Cartilage

55
Q

What can synovial joints be classified into and give examples of these

A

Simple (metacarpophalangeal joint) - One pair of articular surfaces

Compound (elbow joint) - more than one pair of articular surfaces

56
Q

What are 3 main extra-articular structures to support synovial joints

A

Ligaments, tendons and bursa

57
Q

What are the physiological fucntions of joints

A

To serve the functional requirements of the MSK system

Structural support and purposeful motion

58
Q

WHat are the 3 main roles of joints during purposeful motion

A

Stress distribution
Confer stability
Joint lubrication

59
Q

How does the synovial fluid confer stability

A

It acts as an adhesive seal that freely permits sliding motion between cartilaginous surfaces

60
Q

How do ligaments confer stability

A

Provide a second major stabilising influence

61
Q

WHat are the 5 functions of synovial fluid

A

Lubrication of the joint
Facilitates joint movements
Helps minimise wear and tear of joints through lubrication
Aids in the nutrition of articular cartilage
Supplies the chondrocytes (cartilage cells) with O2 and nutrients and remove O2 and waste producets

62
Q

WHere is the synovial fluid located?

A

It fills the joint cavity (

63
Q

How does the synovial fluid not become a static pool

A

It is continuously replenished and absorbed by the synovial membrane

64
Q

Describe the viscosity of the synovial fluid

A

It has a high viscosity - due to the presence of hyaluronic acid (mucin)

65
Q

How does te viscosity of the synovial fluid vary

A

With joint movement

66
Q

What also changes during joint movement

A

The elasticity of synovial fluid

67
Q

What is rapid movement associated with

A

Decreased viscosity and increased elasticity

68
Q

What happens to the viscosity and elasticity of a joint in a diseased joint (osteoarthritis)

A

The viscosity and elasticity become defective

69
Q

Describe the appearance of normal synovial fluid

A

Clear and colourless

70
Q

How many WBC are present

A

Less than 200WBC/mm3

71
Q

What happens to the WBC count in inflammatory and septic arthritis

A

THe count increases

72
Q

What happens to the appearance of synovial fluid in traumatic synovial tap and in haemorrhagic arthritis

A

It turns red

73
Q

what causes the synovial fluid to appear thin and opaque

A

The very high polymorph count

74
Q

What is the main functions of articular cartilage

A

It provides a low fruction lubricated gliding surface to help revent wear and tear of joints
It distributes contact pressure to subchodral bone

75
Q

What plays a significant role in determining the mechanical properties of cartilage

A

The composition of the cartilage ECM and the interaction between the fluid and sold phase

76
Q

What causes the zones to differ in the structure of articular cartilage

A

Organisation of collagen fibres and relative content of cartilage components

77
Q

What are the 4 zones of articular cartilage

A

Superficial
Middle
Deep
Calcified

78
Q

The articular cartilage is usually what?

A

Hyaline

79
Q

Describe the properties of articular cartilage

A

Elastic and sponge like

Covers the articuar surfaces of bones

80
Q

What is articular cartilage made up of

A

Predominantly water (70%) and collaged (20%) and Proteoglycans (10%)

81
Q

Where is the highest proportion of water in the cartilage

A

Near the articular surface

82
Q

What happens to the cartilage water content with age

A

It decreases with age

83
Q

What is the function of water in cartilage?

A

To maintain the resiliency of the tissue and contribute to the nutrition and lubrication system

84
Q

What does collagen provide in cartilage

A

Tensile stiffness and strength

85
Q

Where is the highest concentration of proteoglycan found in the cartilage

A

In the middle and deep zone

86
Q

WHat is proteoglycan composed of

A

Mainly glycosaminoglycan e.g. chondriotin sulphate

87
Q

What happens to the composition of cartilage proteoglycan with age

A

It changes - chondriotin decreases with age

88
Q

What is proteoglycan responsible for

A

The compressive properties associated with load bearing

89
Q

What synthesises, organises , degrades and maintains the ECM

A

Chondroxytes (cartilage cells)

90
Q

Describe the relationship between the rate of ECM degradation and the rate at which it is replaced

A

The rate of ECM degradation doesnt exceed the rate at which it is replaced

91
Q

What would change the mechanical properties of cartilage?

A

Changes in the relative amounts of the three major components of cartilage (water, collagen and proteoglycans)

92
Q

What would occur if the rate of ECM degradation were to exceed the rate of its synthesis

A

Joint disease would occur

93
Q

What are the catabolic factors of cartilage matrix turnover

A

Stimulate proteolytic enzymes and inhibit proteoglycan synthesis

94
Q

What are the anabolic factors of cartilage matrix turnover

A

Stimulate proteoglycan synthesis and counteract effects of IL-1

95
Q

What are the 2 main markers of cartilage degredation

A

Serum and synovial keratin sulphate

Type 2 collagen in synovial fluid

96
Q

What indicates cartilage breakdown

A

Increased levels of both serum and synovial keratin sulphate OR increased evels of type 2 collagen in synovial fluid

97
Q

What happens to the serum and synovial keratin sulphate levels with age?

A

They increase

98
Q

Why is measuring the type 2 collagen in synovial fluid useful?

A

In evaluating cartilage erosion (e.g. in osteoarthritis and rheumatoid arthritis)

99
Q

What gives rise to osteoarthritis

A

Cartilage and synovial composition and function deteriorate with age and repeated wear and tear

100
Q

What causes rheumatoid arthritis

A

Synovial cell proliferation and inflammation

101
Q

What causes gouty arthritis

A

Deposition of salt crystals (uric acid)

102
Q

What causes soft tissue rheumatism (e.g. injury tot he tendon causes tendonitis)

A

Injury and inflammation to periarticular structures

103
Q

Give 6 examples of changes that can occur in an osteoarthritic knee

A
Cyst formation
Sclerosis in subchondral bone 
Osteophyte formation
fibrillated cartilage 
synovial hypertrophy
thickened capsule
104
Q

What histologically causes gouty arthritis

A

Deposition of needle shaped uric acid crystals

105
Q

What causes pseud-gout

A

Deposition of rhomboid shaped calcium pyrophosphate crystals