Gait-(WK15)

Question 1

Define: gait cycle

Answer 1

from IC to IC of same foot.

Question 2

Define: Stance Phase

Answer 2

IC to Pre-Swing; 60% of gait cycle; entire period that foot is on the ground

Question 3

Define: Swing Phase

Answer 3

When foot is in the air; 40% of gait cycle; from IS to TSw

Question 4

Define: Stride Length

Answer 4

distance between IC to IC on same limb

Question 5

Define: Step Length

Answer 5

distance between two successive events on opposite limb

Question 6

Define: Toe Clearance

Answer 6

1.28-1.9 cm is the norm

distance between hallux and floor in swing phase

Question 7

Define: Step Width

Answer 7

7-10cm horizontal distance between two points on opposite limbs

Question 8

Define: Foot Progression Angle

Answer 8

5-7 degrees is the norm

angle between longitudinal axis of foot and line of gait

Question 9

Define: Gait Speed

Answer 9

1.37 M to 1.3 m/sec F

Distance/time in m/sec

Question 10

Define: Cadence

Answer 10

of steps/ minute
M=108
F= 118
steps/minute

Question 11

At what speed does walking usually turn into running ?

Answer 11

at about 4.8-5 mph

Question 12

Describe the start and stop of each period of the gait cycle: Initial Contact

Answer 12

Heel hits the floor

contralateral leg ending terminal stance

Question 13

Describe the start and stop of each period of the gait cycle: Loading Response

Answer 13

initial contact

foot flat; contralateral leg in in pre-swing

Question 14

Describe the start and stop of each period of the gait cycle: Mid-Stance

Answer 14

Foot flat

body over stance limb; contralateral limb in mid-swing

Question 15

Describe the start and stop of each period of the gait cycle:Terminal Stance

Answer 15

midstance

heel off

Question 16

Describe the start and stop of each period of the gait cycle: Pre-Swing

Answer 16

IC ( swing limb)

Toe off ( stance limb)

Question 17

Describe the start and stop of each period of the gait cycle: Initial Swing

Answer 17

Toe Off

feet adjacent; contralateral leg in midstance

Question 18

Describe the start and stop of each period of the gait cycle: Mid Swing

Answer 18

Feet adjacent

vertical tibia

Question 19

Describe the start and stop of each period of the gait cycle: Terminal Swing

Answer 19

vertical tibia

almost IC

Question 20

Write a goal for a patient who has a walking speed of .20m/sec using the MCD or MCID, to improve her speed ( OGA p.6)

Answer 20

Patient will increase walking speed to .50 m/sec in the next one month.

Question 21

Describe the center of mass displacement in the sagittal and frontal planes during the gait cycle.

Answer 21

sagittal : 1-2 inches of displacement; highest during midstance; lowest during LR and PreSw

Frontal: ~3cm; most during mid-stance

Question 22

How does the LoG differ from the GRF during gait ?

Answer 22

LoG is a vertical line to the ground from the CoM most relevant during standing phase in analysis

GRF during gait causes most of the external moments which require internal forces to counteract. The angle of the GRF may change throughout the gait cycle

Question 23

For each period give the GRF, external moment direction, and muscle activity at each major lower body joint: Initial Contact

Answer 23

HIP:
GRF: anterior
EM: flexion moment
Muscle: Hip Extensors

KNEE JOINT:
GRF: anterior
EM: Extension
Muscle: vastus muscles

ANKLE JOINT:
GRF: posterior
EM: plantar flexion
Muscle: dorsiflexors

Question 24

For each period give the GRF, external moment direction, and muscle activity at each major lower body joint: Loading Response

Answer 24

HIP:
GRF: anterior
EM: flexion
Muscle: Hip Extensors

KNEE JOINT:
GRF: posterior
EM: flexion
muscle: vastus muscles

ANKLE JOINT:
GRF: posterior
EM: PF
Muscle: dorsiflexors

Question 25

For each period give the GRF, external moment direction, and muscle activity at each major lower body joint: Midstance

Answer 25

HIP: GRF: anterior to posterior EM: flexion to extension Muscle: None KNEE JOINT: GRF: posterior to anterior EM: flexion to extension Muscle: Only vasti during flexion moment ANKLE JOINT: GRF: anterior EM: DF Muscle: Plantar flexors

Question 26

For each period give the GRF, external moment direction, and muscle activity at each major lower body joint: Terminal Stance

Answer 26

HIP: GRF: posterior EM: Extension Muscle: none KNEE JOINT: GRF: anterior then moves posterior before IC EM: extension to flexion before IC Muscle: No muscle activity ANKLE JOINT: GRF: anterior EM: DF Muscle: plantar flexors

Question 27

For each period give the GRF, external moment direction, and muscle activity at each major lower body joint:PreSw

Answer 27

HIP: GRF: posterior EM: Decreasing extension Muscle: adductor longus and rectus femoris KNEE JOINT: GRF: posterior EM: flexion M: Rectus Femoris ANKLE JOINT: GRF: anterior EM: DF M: Elastic recoil of plantar flexors

Question 28

For the following rockers give the period of gait, GRF involved, and active or passive structures involved: Heel

Answer 28

Period: IC- LR GRF: posterior PF Structures: pretibials control PF

Question 29

For the following rockers give the period of gait, GRF involved, and active or passive structures involved: Ankle

Answer 29

Period: LR- MS GRF: anterior DF PF's eccentrically control DF

Question 30

For the following rockers give the period of gait, GRF involved, and active or passive structures involved: Forefoot

Answer 30

Period: MS-TS GRF: anterior DF MTP fulcrum, PF's

Question 31

For the following rockers give the period of gait, GRF involved, and active or passive structures involved: Toe

Answer 31

TS-PreSw GRF: anterior DF PF passive recoil

Question 32

Why does toe drag occur in initial swing vs mid-swing

Answer 32

initial swing: lack of knee flexion mid swing: lack of ankle dorsiflexion

Question 33

What muscles are involved in maintaining the medial longitudinal arch during each period of the gait cycle ?

Answer 33

TA and TP are eccentrically active during LR TP is active eccentrically during early MS and concentrically during late MS TP concentric during TS

Question 34

Compare gait differences between a young child and an older adult

Answer 34

child: short steps, uneven step length, IC w flat foot, decreased stride length and cadence Older adult: decreased velocity, strides, and step length, wide BoS, may need AD.

Question 35

How does an AFO prevent genu recurvatum ?

Answer 35

external support would force the knee to flex, accentuating heel rocker, keeps ankle in neutral.