Lecture 1 (Gait Theory, Velocity, Cycle, Temporal Parameters)

Question 1

What are the two theories of gait?

Answer 1

Six determinants of gait and inverted pendulum

Question 2

What does the six determinants of gait theory follow?

Answer 2

Kinematic theory

Question 3

What does the six determinants of gait hypothesize?

Answer 3

Energy expenditure during gait (horizontal and vertical displacements) is minimized by the 6 actions of the pelvis, hip, knee and ankle

Question 4

What are the 6 major gait features? Which planes?

Answer 4

Sagittal:
Hip and knee flexion
Knee and ankle flexion

Transverse:
Pelvic rotation

Frontal:
Lateral pelvic tilt

Question 5

What does pelvic rotation affect?

Answer 5

Stride length; more rotation = longer stride and vice versa

Question 6

Which sex experiences a more noticeable pelvic tilt when walking? Why?

Answer 6

Females b/c their glute med is susceptible to be weak

Question 7

What is gait kinematic?

Answer 7

Study of motion of mechanical points of joints during upright mobility

Question 8

What does gait kinematic involve?

Answer 8

Extent of joint movement (ROM), speed, direction (joint motion)

Question 9

What are the two major phases in the 6 determinant theory?

Answer 9

Stance and swing phase

Question 10

What does the inverted pendulum theory state?

Answer 10

Stance leg is kept relatively straight during single support, functioning like inverted pendulum

Question 11

How does the COM differ between the two theories?

Answer 11

6 determinant: reduced COM displacement, stays in a straight line

Inverted pendulum: COM travels in a series of arcs

Question 12

What act as the “propellers” during the push/toe off?

Answer 12

Gastroc and soleus

Question 13

What is gait speed measured in? What are normative values based on?

Answer 13

Meters/sec; age and sex

Question 14

What are the functional ambulatory terms for rehabilitation medicine?

Answer 14

-Safely cross the street (1.3 m/s)
-Community ambulation
-Limited community ambulator
-Household ambulator
-Dependent ambulator (requires assistance of a person)

Question 15

How can you describe someone’s normal comfortable speed of gait?

Answer 15

Preferred, natural, self-selected, free

Question 16

What’s the ideal walking speed for better outcome? What speed increases risk of falls etc?

Answer 16

1.0 m/s; 0.7 m/s

Question 17

What is stance phase? What % of gait cycle?

Answer 17

When a foot is in contact w/ the ground, heel-strike to toe-off; 60% of gait cycle

Question 18

What is the swing stance? What % of gait cycle?

Answer 18

Foot is not in contact w/ ground; 40%

Question 19

What % in a full gait cycle does a double support occur?

Answer 19

22%

Question 20

What are the spatial parameters?

Answer 20

Step length, stride length and step width

Question 21

What is step length?

Answer 21

Calcaneus to contralateral foot calcaneus

Question 22

What is stride length?

Answer 22

Calcaneus to calcaneus of ipsilateral calcaneus

Question 23

What is step width?

Answer 23

Mid point of calcaneus to midpoint of calcaneus

Question 24

How does foot angle affect gait?

Answer 24

Wide foot angle can decrease stride length

Question 25

What are the critical foundational measures in PT?

Answer 25

Step and stride length

Question 26

What are the determinants of stride length?

Answer 26

Age, injury/illness, height, sex (males>)

Question 27

What is cadence? What is normal range for adults?

Answer 27

of steps per minutes; 80-90 steps/min

Question 28

How to calculate gait velocity

Answer 28

Cadence x stride length

Question 29

How does a shorter and longer step length affect cadence?

Answer 29

Shorter -> increased cadence
Longer -> decreased cadence