Week 8 (Gait Cycle)

Question 1

Normal value of speed

Answer 1

1.4m/s

Question 2

Normal value of cadence

Answer 2

90-120 steps/min

Question 3

Normal value of step length

Answer 3

0.72m

Question 4

Normal value of stride length

Answer 4

1.44m

Question 5

Joint angles: ankle

Answer 5

• Heel strike: ankle in plantar grade
• Foot flat: ankle lowers into plantar flexion
• Stance: ankle comes into more dorsiflexion as hips move in front of the body throughout stance
• Toe-off: powerful plantar flexion push-off
• Swing: dorsiflexion in first half which is maintained for the rest of swing

Question 6

Joint angles: knee

Answer 6

• Heel strike: knee is in little flexion then flexes more for knee yield
• Stance: extends in mid stance to keep leg straight
• Late stance: flexes to clear foot off the ground
• Swing: continues smoothly into more flexion to keep clearing the foot before extending out in mid to late swing to swing the leg forward
• Late swing: in some flexion to hit the ground again

Question 7

Joint angles: hip

Answer 7

• Heel strike: hips start in flexion
• Stance: hip gradually going into extension from initial flexed position
• Toe-off: hip flexes to pull the leg off the ground
• Swing: hip flexes and continues before evening out and dipping down before next heel strike

Question 8

What is the main difference in joint angles when walking fast and slow?

Answer 8

More knee flexion in fast walking

Less knee flexion in slow walking

Question 9

During stance, our hip is in adduction or abduction?

Answer 9

Adduction

Question 10

Pelvic shift: what happens at weight acceptance?

Answer 10

Individual shifts laterally to keep COM close to stance foot and pelvis drops on unsupported side

Question 11

Important components during stance phase?

Answer 11

• Extension of hip throughout
• Flexion of knee on heel strike then extension through mid stance and flexion prior to toe-off
• Dorsiflexion of the ankle until the end of stance and then fast plantar flexion
• Lateral horizontal shift of the pelvis and trunk

Question 12

Important components during swing phase?

Answer 12

• Flexion of knee with hip in extension
• Hip flexion
• Dorsiflexion of ankle throughout
• Slight lateral pelvic tilt downwards
• Rotation of pelvis forward
• Extension of knee prior to heel strike

Question 13

Power =

Answer 13

Energy/time

Question 14

Concentric contraction creates what type of power

Answer 14

Positive

Question 15

Eccentric contraction creates what type of power

Answer 15

Negative

Question 16

Clinical measurements of walking

Answer 16

• Timed 10m walk test (common)
• 6 min walk test
• Item 5 of MAS scale

Question 17

Clinical measurements of stair ability

Answer 17

• Item 5 of MAS scale

- Timed ascent/descent of flight stairs

Question 18

Kinematics of stair ascent

Answer 18

• Knee going into flexion and hip going into extension to straighten the stance leg on the step
• Ankle doesn’t change much
• In swing, hip and knee come into flexion to step up the next step and come back down for the next step

Question 19

Kinetics of stair ascent

Answer 19

• Almost all concentric; need to be able to lift bw
• Knee and hip initially generating most power
• Before-toe off, ankle takes over to push up

Question 20

Kinematics of stair descent

Answer 20

• Knee comes into flexion
• Ankle and hip don’t change much
• Need to be able to lift knee to come down to next step
• Angle of knee flexion change as we go down

Question 21

Kinetics of stair descent

Answer 21

Almost all eccentric to control lowering of body

- Starts off being controlled at ankle before controlled at knees as you move further down the stair

Question 22

<0.4m/s are

Answer 22

Household ambulators

Question 23

0.4-0.8m/s are

Answer 23

Limited community ambulators

Question 24

0.8> are

Answer 24

Community ambulatory

Question 25

What position is the hip, knee and ankle in during heel strike

Answer 25

Hip: flexion
Knee: slight flexion
Ankle: plantargrade or slight df

Question 26

What position is the hip, knee and ankle in during stance phase

Answer 26

Hip: extension movement
Knee: extension movement
Ankle: dorsiflexion

Question 27

What position is the hip, knee and ankle in during toe-off

Answer 27

Hip: extension
Knee: flexion
Ankle: plantarflexion

Question 28

What position is the hip, knee and ankle in during swing phase

Answer 28

Hip: flexion movement
Knee: extension movement
Ankle: dorsiflexion

Question 29

What are the 2 power outputs for the ankle

Answer 29

A1: eccentric dorsiflexors to control knee going over foot during mid-stance and terminal stance
A2: concentric plantar flexors to push-off during pre-swing

Question 30

What are the 4 power outputs for the knee

Answer 30

K1: eccentric knee extensors to control knee flexion during loading response
K2: concentric knee extensors to initiate knee extension during mid stance
K3: eccentric knee flexors to control knee flexion from plantar flexion push-off during pre-swing
K4: eccentric knee flexors decelerate the swinging extremity during terminal swing

Question 31

What are the 3 power outputs for the hip

Answer 31

H1: concentric hip extensor when hips move from flexion into extension during loading response
H2: eccentric hip flexors to control body moving over the midline during mid stance
H3: concentric hip flexors to powerfully pull-off during pre-swing and initial swing