Lecture 2: Gait Kinematics

Question 1

What are two methods to analyze gait?

Answer 1

Kinematic and breaking gait into 8 subphases of swing and stance

Question 2

What are the different subphases in stance?

Answer 2

initial contact, loading response, mid stance, terminal stance, pre-swing

Question 3

What are the different subphases in swing?

Answer 3

initial swing, mid swing, terminal swing

Question 4

What is the task of initial contact and loading response?

Answer 4

weight acceptance

Question 5

What is the task of midstance, terminal stance?

Answer 5

single limb support

Question 6

What is the task of pre-swing, initial swing, mid swing, and terminal swing?

Answer 6

swing limb advancement

Question 7

Which subphases of stance are in double support? Single support?

Answer 7

Double support: IC, LR, Pre-swing

Single support: mid stance, terminal stance

Question 8

What is torque?

Answer 8

-angular force or joint moment
-measure of force that can cause an object to rotate about an axis

Question 9

What is the gait term for torque? Definition

Answer 9

joint moment - amount of force required to stabilize or create movement in a joint axis

Question 10

First subphase? Critical event?

Answer 10

-initial contact
-heel contact w/ ground

Question 11

Ankle, knee and hip ROM for IC in sagittal plane

Answer 11

Ankle: ROM at 0 degrees (heel rocker initiated)

Knee: 0-5 degrees (contact creates a moment/torque)

Hip: 20 degrees flexion (high intensity torque)

Question 12

Second subphase? Critical event?

Answer 12

-loading response
-hip stability, knee stability (shock absorption), ankle PF

Question 13

Ankle, knee and hip ROM for loading response in sagittal plane

Answer 13

Ankle: 5 degrees PF (heel rocker initiated)

Knee: 15 degrees (shock absorption)

Hip: 20 degrees flexion (high torque: 2nd highest torque demand for stability)

Question 14

3rd subphase? Critical event?

Answer 14

-midstance
-controlled tibial advancement

Question 15

Ankle, knee, and hip ROM for midstance in sagittal plane

Answer 15

Ankle: moves to 5 degrees PF, foot in closed chain position, talocrural joint moves over fixed foot , ankle 2nd rocker is obtained

Knee: moves into extension (still maintains 5 degrees flexion)

Hip: extends to neutral, pelvis and hip are stabilized

Question 16

Briefly describe midstance biomechanics

Answer 16

fixed foot (ankle rocker) with tibial advancement, talocrural joint is fulcrum

Question 17

What are the 4 types of midstance biomechanics

Answer 17

heel rocker, ankle rocker, forefoot rocker, toe rocker

Question 18

What is heel rocker?

Answer 18

contact of calcaneus with ground

Question 19

What is ankle rocker?

Answer 19

fixed foot with full foot contact

Question 20

What is forefoot rocker?

Answer 20

calcaneus moves out of contact, forefoot contact

Question 21

What is toe rocker?

Answer 21

great toe serves as the base of contact

Question 22

4th subphase? critical event?

Answer 22

-terminal stance
-controlled DF with heel raise (force generation for propulsion forward)

Question 23

Ankle, knee, and hip ROM for terminal stance in sagittal plane

Answer 23

Ankle: moves to 10 degrees DF, 1st metatarsal moves to 30 degrees of flexion, 3rd ankle rocker or forefoot rocker emerges

Knee: 0-5 degrees, calf increases motor function and prevents collapse of loaded limb

Hip: extends to 20 degrees

Question 24

What does the trailing limb allow?

Answer 24

greater step length
key importance for clinical interventions

Question 25

5th subphase? Critical event?

Answer 25

-pre-swing -passive knee flexion to 40 degrees, ankle PF

Question 26

Ankle, knee, and hip ROM for pre-swing

Answer 26

Ankle: 15 degrees PF, MT 60 degrees flexion, fore foot contact to first MT contact (toe rocker) Knee: 40 degrees flexion, critical for knee to clear foot in preparate Hip: 10 degrees extension, limb advancement begins

Question 27

Initial swing critical event

Answer 27

hip flex 15 degrees, knee flex to 60 degrees

Question 28

Ankle, knee, and hip ROM for initial swing in sagittal plane

Answer 28

Ankle: moves to 5 degrees of PF (moves toward neutral) Knee: moves to 60 degrees Hip: flexion to 15 degrees

Question 29

Mid swing critical event

Answer 29

hip flex to 25, DF to 0

Question 30

Ankle, knee, and hip ROM for mid swing in sagittal plane

Answer 30

Ankle: moves to neutral 0 degrees (clears ground by 1 cm) Knee: moves rapidly to ext, moves to 25 degrees Hip: flexion to 25 degrees

Question 31

Terminal swing critical event

Answer 31

knee ext to neutral (or 5 degrees of flex)

Question 32

Ankle, knee and hip ROM for terminal swing in sagittal plane

Answer 32

Ankle: DF to neutral Knee: extends to neutral (or 5 degrees flex), active quads to achieve step length Hip: flex to 20 degrees

Question 33

How much does the pelvis anteriorly tilt anatomically?

Answer 33

10 degrees

Question 34

How much does the pelvis tilt with ambulation? Which phase?

Answer 34

-additional 4 degrees anteriorly -terminal stance

Question 35

When does pelvic tilt in front plane? How much?

Answer 35

-during weight acceptance -contralateral side of pelvis drops 4 degrees

Question 36

What are the frontal plane kinematics in the hip?

Answer 36

Stance phase limb on R -stabilizes the hip and pelvis from initial contact through pre swing

Question 37

How much movement occurs in hip from initial contact to end of loading response in frontal plane?

Answer 37

0 to 10 degrees ADD

Question 38

Knee kinematics in frontal plane on stance phase

Answer 38

Knee must stay in alignment w/ hip and ankle (no varus or valgus)

Question 39

What is the subtalar joint responsible for?

Answer 39

Supination and pronation

Question 40

What happens to the subtalar joint during loading response in the frontal plane? What does this unlock and assist with?

Answer 40

Calcaneus everts 5 degrees and the subtalar joint moves into pronation Unlocks midtarsal joints Assists in ankle shock absorption and reduces stress of loading impact

Question 41

What happens to the tibia when calcaneus everts

Answer 41

IR

Question 42

What happens to the subtalar joint during late terminal stance? What does this do to midtarsal joints? What does it promote?

Answer 42

Subtalar calcaneus version reduces from 5 to 2 degrees Increases their stability - creates rigid forefoot level in terminal stance moving toward supination Promotes 3rd rocker (forefoot rocker)

Question 43

Describe the pelvis rotation in transverse plane during terminal stance, mid swing and terminal swing

Answer 43

TStance - pelvis retraction 5 degrees Mid swing - pelvis neutral TSwing - pelvis forward rotation 5 degrees

Question 44

Describe trunk rotation in transverse plane

Answer 44

Thoracic rotation results in shoulder forward rotation and creates arm swing; rotation coincides w/ contralateral pelvis rotation