Normal and Pathological gait

Question 1

How many steps does an average person take

Answer 1

5000

4km per day

Question 2

Describe the human gait

Answer 2

bipedal
reciprocating
upright
terrestrial

Question 3

What is the fastest recorded human speed?

Answer 3

28 mph

Question 4

List the 4 functional requirements of gait

Answer 4

shock absorption
stability
propulsion
energy conservation

Question 5

How is shock absorption achieved and why is it necessary

Answer 5

shortening the limbs

prevent damage to joints

Question 6

What are the three types of stability?

Answer 6

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

Question 7

What are the main challenges to stability?

Answer 7

• top heavy anatomy
• mobility of the joints
• morphology of the skeletal system

Question 8

As step width increases what decreases?

Answer 8

step length

Question 9

How do we propel ourselves forward?

Answer 9

move centre of mass forward

Question 10

Why doe walking require energy?

Answer 10

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

Question 11

What is normal toe clearance when walking?

Answer 11

~1.2+- 0.4 cm

Question 12

Pathological gait

Answer 12

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

Question 13

What is stride length = to?

Answer 13

right step length + right step length

Question 14

What is stride time = to?

Answer 14

cdence^-1

Question 15

What is a stride?

Answer 15

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

Question 16

%stance
%swing
%double support

Answer 16

60
40
10

Question 17

List the three methods of modeling the gait

Answer 17

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

Question 18

Power =

Answer 18

angular velocity x F X d

Question 19

Generating power at a joint =

Answer 19

moment + velocity

Question 20

Absorbing power at a point =

Answer 20

moment - velocity

Question 21

In what way does GRF change?

Answer 21

position
orientation
magnitude