Normal and Pathological gait Flashcards Preview

Lower Limb Biomechanics and prosthetics > Normal and Pathological gait > Flashcards

Flashcards in Normal and Pathological gait Deck (21)
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1
Q

How many steps does an average person take

A

5000

4km per day

2
Q

Describe the human gait

A

bipedal
reciprocating
upright
terrestrial

3
Q

What is the fastest recorded human speed?

A

28 mph

4
Q

List the 4 functional requirements of gait

A

shock absorption
stability
propulsion
energy conservation

5
Q

How is shock absorption achieved and why is it necessary

A

shortening the limbs

prevent damage to joints

6
Q

What are the three types of stability?

A
joint (prevent bucking of joints against gravity)
global (keep centre of mass within base of support)
foot clearance (prevent stumbling)
7
Q

What are the main challenges to stability?

A
  • top heavy anatomy
  • mobility of the joints
  • morphology of the skeletal system
8
Q

As step width increases what decreases?

A

step length

9
Q

How do we propel ourselves forward?

A

move centre of mass forward

10
Q

Why doe walking require energy?

A

gait is inherently efficient
step to step transition
balance control
aberrant movement and muscle (co)activation

11
Q

What is normal toe clearance when walking?

A

~1.2+- 0.4 cm

12
Q

Pathological gait

A

Inadequate sock absorption –> risk of injury
Unstable –> risk of falls, require walking aids
Impaired propulsion–> necessitates compensatory motion
Excessive energy expenditure –> reduced in walking endurance/ capacity

13
Q

What is stride length = to?

A

right step length + right step length

14
Q

What is stride time = to?

A

cdence^-1

15
Q

What is a stride?

A

from initial contact pf one foot until the next initial contact of the same foot

16
Q

%stance
%swing
%double support

A

60
40
10

17
Q

List the three methods of modeling the gait

A
Single point model
inverted pendulum
rigid segment (assumes, pint joints, rigid segments, 3 planes of movement)
18
Q

Power =

A

angular velocity x F X d

19
Q

Generating power at a joint =

A

moment + velocity

20
Q

Absorbing power at a point =

A

moment - velocity

21
Q

In what way does GRF change?

A

position
orientation
magnitude