Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biomechanics > biomechanics of skeletal tissue > Flashcards

biomechanics of skeletal tissue Flashcards

1
Q

what gives bone its hardness and rigidity

A

calcium and phosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

another name for compact bone

A

cortical bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

basic structural unit of cortical bone

A

haversian system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what layer of bone does cortical bone form

A

outer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what do haversian canals contain

A

blood vessels and nerve fibres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are the layers called that form cylinders round the haversian canals

A

lamellae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are the cavities called that contain osteocytes

A

lacunae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what connects osteocytes to haversian canals and other lacunae

A

minute channels called canaliculi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is each haversian system surrounded by

A

cement like ground substance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the inner part of bone called

A

cancellous or spongy bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what do the spaces between the mesh of cancellous bone contain

A

red bone marrow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

basic structural unit of cancellous bone

A

trabecula

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

equation for stress

A

force / area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

units for stress

A

Nm-2 (N/m2)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

equation for strain

A

change in length / original length

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what does youngs modulus describe

A

how flexible or stiff a material is

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

equation for youngs modulus

A

stress / strain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

units for youngs modulus

A

same as stress since strain has no units

> N m-2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what does small youngs modulus mean

A

the material is flexible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what are the 2 types of bending loading

A

cantilever (one end fixed and load applied at the other end)

3 point

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is the neutral axis

A

between the side of an object being compressed and the side being elongates. if symmetrical this is along the geometric centre.
along this line there is NO DEFORMATION

22
Q

is bone stronger under compression or tension

A

compression

23
Q

appearance of fracture resulting from torsional loading

A

spiral

24
Q

how are long bones designed to resist torsion loads

A

they are hollow with strong cortical bone outer layer

|&raquo_space; strength to weight ratio maximised

25
Q

why are torsional fractures of the tibia more common distally

A

because the cross sectional area is smaller at the distal end so less able to resist torsional loads

26
Q

what is wolffs law

A

bone is laid down where needed and resorbed where not needed

27
Q

why may fracture fixation cause bone atrophy

A

‘stress shielding’ - the plate will carry most of the load&raquo_space; Bone weakens

28
Q

do children have a greater or smaller proportion of collagen

A

greater

29
Q

what is a greenstick fracture

A

incomplete fracture
one end buckled
one and bent
more common in kids because their bones are more flexible due to higher proportion of collagen

30
Q

at what age does bone tissue begin to be lost

A

35 - 40

31
Q

what type of cartilage covers surfaces of bones in synovial joints

A

hyaline

32
Q

what type of cartilage forms the IV discs

A

fibro cartilage

33
Q

articular cartilage composition and structure

A

mainly made up of collagen structured into fibrils

the fibrils are meshed in a concentrated solution of proteoglycans

34
Q

in articular cartilage where are proteoglycans most concentrated

A

middle portion

35
Q

what cells in artic cartilage manufacture, secrete and maintain the organic matrix

A

chondrocytes

36
Q

what is below the deep zone of articular cartilage than then merges with subchondral bone, and what is this interface called?

A

calcified cartilage

interface between artic cartilage and calcified cartilage = “tidemark”

37
Q

is artic cartilage

  • elastic
  • viscous
  • viscoelastic
A

viscoelastic

38
Q

articular cartilage - when load removed will it return to normal?

A

yes but the response is not immediate

39
Q

what two properties does articular cartilage display

A

creep

stress relaxation

40
Q

what is creep

A

increase in strain under a constant stress

41
Q

what is stress relaxation

A

reduction in stress under a constant strain

load required to maintain the deformation decreases with time

42
Q

name the 3 main types of lubrication in synovial joints

A

elastohydrodynamic
boosted
boundary

43
Q

what characteristic of articular cartilage does boosted lubrication rely on?

A

its permeability

44
Q

describe the permeability of articular cartilage and how this enhances lubrication

A

it is permeable only to small molecules such as water. as the gap between the 2 surfaces becomes smaller, resistance to sideways flow of lubricant becomes greater than resistance of small molecules into the articular cartilage&raquo_space; water moves into the cartilage, leaving a thick viscose gel behind&raquo_space; enriched lubricant

45
Q

describe boundary lubrication

A

if loads are sustained for long enough to deplete fluid completely, lubricant molecules attach themselves chemically to the surfaces creating a boundary layer. this layer has a low shear strength, offering a lower friction than the bare surfaces

46
Q

what is the protein in synovial joints that acts as boundary lubrication

A

lubricin

47
Q

what do tendons and ligaments both contain

A

fibroblasts

48
Q

in which are the collagen fibres parallel:

tendons or ligaments? why?

A

tendons

because the need to withstand large loads in one direction only

49
Q

which is bone - bone and which is bone - muscle

A 
tendon = muscle - bone 
ligament = bone - bone
50
Q

are tendons and ligaments

  • elastic
  • viscous
  • viscoelastic
A

viscoelastic

51
Q

do tendons and ligaments display creep and stress relaxation?

A

yes

52
Q

beyond joint displacement of how much will pain and damage occur in the ACL
beyond what will it rupture

A

> 4mm - pain and damage

> 7 mm - rupture

Biomechanics (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions