Lec 1: Gait Theory and Spatial Temporal Parameters

Question 1

Six determinants of gait theory states…

Answer 1

energy costs during gait (vertical and horizontal) is minimized by the six actions of pelvis, hip, knee, and ankle
these six actions are responsible for reducing work expenditure during gait

Question 2

6 gait features and their planes

Answer 2

Sagittal plane:
1-2: Hip and knee flexion
3-4: Knee and ankle flexion
Transverse plane:
5: Pelvic rotation
Frontal plane:
6: Lateral pelvic tilt

Question 3

Six determinant theory is based upon… (and define)

Answer 3

Gait kinematics: study of motion of mechanical points of joints during upright mobility, involving:
1. extent of joint movement (ROM)
2. speed (velocity of body and limbs)
3. direction of joint motion (flexion, extension)

Question 4

Premise 1 and 2 of six determinants theory

Answer 4

Premise #1: gait is translation of COM through space along pathway requiring least expenditure of energy
Premise #2: minimizing amount that body’s COG is displaced from line of progression reduces muscular effort of walking (=saving energy)

Question 5

Inverted pendulum theory states

Answer 5

stance leg is kept relatively straight during single support (fx like inverted pendulum)
-COM (near hip) travels in series of arcs through each single support phase
-stance limb travels like pendulum (=does not require much energy)

Question 6

Gait is measured by…

Answer 6

1. m/s
2. age
3. sex
4. level of community access

Question 7

Functional ambulatory terms for rehabilitation medicine (with or without assistive device)

Answer 7

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

Question 8

Gait velocity (m/s) indications

Answer 8

> 1 m/s = predictive of completing yard work and climbing flights of stairs
<1 m/s = benefit from fall prevention, complete self care and household activities
<0.60 m/s = predicts future risk of falls and hospitalization, tend to require assistance with ADL/IADL, cross street
<0.40 m/s = longer length of stay in acute care, likely to discharge to skilled nursing/in patient rehab/nursing home/home health services

Question 9

Two phases of gait cycle=

Answer 9

Stance phase (60% w/ 20% double support) = during a walking cycle, a given foot is in contact with the ground, heel-strike to toe-off
Swing phase (40%) = during a walking cycle, a given foot is not in contact with ground

Question 10

Double support period of gait cycle occurs…

Answer 10

between reference limb initial contact and contralateral limb toe off
each double support period occupies =11% (22% for a full cycle)
body supported by single limb for =80% of cycle

Question 11

Gait cycle spans period between

Answer 11

initial contact of reference extremity and successive contact of same extremity

Question 12

Spatial Parameters of gait include

Answer 12

1. Step length= reference limb calcaneus to contralateral limb calcaneus
2. Stride length= reference limb calcaneus to successive reference limb calcaneus
3. Step width= midpoint of reference limb calcaneus to midpoint of contralateral limb calcaneus
4. Foot angle

Question 13

Foundational measures of gait in PT

Answer 13

Step and stride length

Question 14

Determinants of stride length

Answer 14

age, height, males>, injury/illness**

Question 15

Gait Temporal Parameters

Answer 15

1. Gait velocity (1.2-1.4 m/s for adults)= determinated by sex and age, essential for PT
2. Cadence (80-90 steps/min for adults)= number of steps/min
   —> shorter step length = increase cadence at any velocity
   —> longer step length = decrease cadence at any velocity
3. Swing time or stance time (seconds)

Question 16

Clinical application for gait velocity, stride length, and level of community ambulation

Answer 16

1. gait velocity= in all settings, determines discharge preferences, intervention outcomes
2. stride length= injuries (orthopedic), neurological clients
3. level of community ambulation

Question 17

Calculation of gait velocity

Answer 17

Gait Velocity = cadence X stride length
e.g. 80 steps per minute X 0.9 meter = 72 min/m —> .72 m/s