Gait Cycle Lecture 1 + 2

The five categories of gait analysis are

temporal-spatial

Kinematic

Kinetic

Muscle activity

energy cost

The four essential requirements for walking are

Support

balance

propulsion

Limb swing

Additional gait goals include

Minimizing pain

Conserving energy

Maintaining smoothness

A gait cycle is normalized from _____ to _____%.

0,100

A stride is one complete gait cycle from an event to the next occurrence of the same event on the _____ limb.

same

Stance phase comprises approximately _____% of the gait cycle.

60

Swing phase comprises approximately _____% of the gait cycle.

40

Double support occurs _____ times during a gait cycle.

two

Each period of double support is approximately _____% of the gait cycle.

10

Each period of single support is approximately _____% of the gait cycle.

40

The center of mass reaches its greatest height during _____.

mid stance

The center of mass is lowest during _____.

double support

Loading Response begins at _____ and ends at _____

Initial contact, oppo toe off

The primary task of Loading Response is _____.

Weight acceptance

The three functional demands of weight acceptance are

Shock absorption

Initial limb stability

Presevation of progression

During Initial Contact the hip is _____, the knee is ____, the ankle is ____.

flexed, extended, dorsiflexed to neutral

The limb is "reaching" for the ground during _____.

Initial Contact

A major objective of Initial Contact is _____.

Impact deceleration

During Loading Response the knee _____ for shock absorption.

flexes

During Loading Response the ankle undergoes controlled _____.

plantar flexion

Peak plantar flexion during Loading Response is approximately _____°.

10

During Loading Response the _____ act _____ to ______

dorsiflexors, eccentrically, prevent foot slap

During Loading Response the knee _____ initially act _____ to begin _____

flexors, concentrically, knee flexion

The knee ______ act _____ during Loading Response to _____.

extensors, eccentrically, control knee flexion

The hip _____ act _____ then _____ during Loading Response.

extensors, isometrically, concentrically

A primary role of the hip _____ during Loading Response is ______.

extensors, Preventing trunk jackknifing

The task of Mid Stance is single-limb _____.

support

During Mid Stance the ankle _____, and the hip and knee ______

dorsiflexes, extend

A key objective of Mid Stance is _____ over the foot and _____

Controlled tibial progression, limb + trunk stability

Peak center of mass height occurs during _____.

Mid Stance

The ____ act _____ during Mid Stance to _____

Plantar flexors, eccentrically, control tibial progression

The knee _____ act _____ during Mid Stance to ______ AND the knee ______ act ______ to _________

Extensors, concentrically, extend the leg

flexors, eccentrically, prevent hyperextension

During Terminal Stance the hip and knee are in _____.

extension

A major objective of Terminal Stance is moving the center of mass ahead of the _____.

forefoot

Terminal Stance requires a rigid foot and _____.

ankle

Peak hip ____ during Terminal Stance is approximately _____°.

extension, 10

Peak ankle _____ during Terminal Stance is approximately _____°.

dorsiflexion, 10

The plantar flexors are the primary contributor to forward _____.

propulsion

The _____ act _____ to control _____ during Terminal Stance.

plantar flexors, eccentrically, tibial progression

The _____ also act _____ to provide push-off.

plantar flexors, concentrically

The hip ____ act _____ to ______ during Terminal Stance.

flexors, eccentrically, decelerate hip extension

The primary task of Pre-Swing is _____.

swing limb advancement

Pre-Swing is also known as weight ______ and weight _____.

release, transfer

Double support is _____ during Pre-Swing.

initiated

Ankle _____, _____ during Pre-Swing.

Plantar flexion, increases

The knee _____ during Pre-Swing.

flexes

Hip _____ is _____ during Pre-Swing.

extension, reduced

A major objective of Pre-Swing is positioning the limb for _____.

swing

Another objective of Pre-Swing is accelerating the trailing limb with a forward _____.

push

Peak ankle plantar flexion occurs during Pre-Swing at approximately _____ to _____ degrees.

15;20

The hip _____ act _____ to initiate hip flexion in Pre-Swing.

flexors, concentrically

The knee _____ act _____ to limit knee flexion rate.

extensors, eccentrically

The task of Initial Swing is _____.

swing limb advancement

Knee _____ lifts the foot for toe _____ during Initial Swing.

flexion, clearance

Hip _____ advances the _____ during Initial Swing.

flexion, limb

Ankle _____ is _____ during Initial Swing.

dorsiflexion, incomplete

Foot clearance is controlled mainly by knee _____.

flexion

Peak knee flexion during Initial Swing is approximately _____°.

60

The _____ act _____ during Initial Swing to bring the ankle toward neutral.

dorsiflexors, concentrically

During Mid Swing, limb advancement is achieved by further hip _____.

flexion

The knee _____ during Mid Swing.

extends

The ankle _____ to _____ during Mid Swing.

dorsiflexes, neutral

The major objectives of Mid Swing are

limb advancement and foot clearance

Peak hip flexion occurs during Mid Swing at approximately _____°.

32

The hip _____ act _____ during Mid Swing to decelerate hip flexion.

Extensors, eccentrically

The ankle _____ act _____ or _____ during Mid Swing.

dorsiflexors, concentrically, isometrically

During Terminal Swing, limb advancement is completed by knee _____.

extension

The hip _____ during Terminal Swing.

Extends slightly

The ankle remains _____ during Terminal Swing.

dorsiflexed

A primary objective of Terminal Swing is preparing for _____.

ground contact

The knee _____ act _____ during Terminal Swing to decelerate knee _____.

Flexors, eccentrically, extension

The hip _____ act _____ during Terminal Swing to prepare for Initial Contact.

extensors, concentrically

The ankle _____ act _____ or _____ to maintain a neutral ankle during Terminal Swing.

Dorsiflexors, concentrically, isometrically

Near full knee extension is achieved just prior to _____.

Initial Contact

The pelvis demonstrates approximately _____° of anterior tilt throughout gait.

3

The pelvis tilts _____ during double support and _____ during single-limb support

posteriorly, anteriorly

Peak hip _____ occurs during _____ Swing.

flexion, Mid

Peak hip _____ occurs during _____.

extension, Pre-Swing

Peak knee _____ occurs during _____ Swing.

flexion, Initial

The ankle is _____ at Initial Contact.

neutral

Controlled ankle _____ occurs during _____ Response.

Plantar flexion, Loading

Peak plantar flexion occurs at _____.

Toe Off

Stride length is the distance between consecutive heel strikes of the _____ limb.

same

Step length is the distance between consecutive heel strikes of _____ limbs.

opposite

Step width is the lateral distance between heel centers of consecutive foot _____.

contacts

Gait speed equals _____ multiplied by stride _____.

stride length x frequency

The most functional measure of walking ability is _____.

gait speed

Average gait speed is approximately _____ m/sec.

1.37

To increase walking speed, stride _____ and stride _____ can be increased.

Length, frequency

Vertical ground reaction force has _____ peaks during normal walking.

two

The vertical GRF peaks are approximately _____% body weight.

120

The valley in vertical GRF is approximately _____% body weight.

80

Anterior-posterior ground reaction forces consist of _____ and _____.

propulsion, braking

the point through which the resultant ground reaction force appears act

Center of pressure

Humans select a stride length and frequency that minimizes

Step-to-step transition costs

Leg swing costs

Minimum cost of transport occurs near _____ m/sec.

1.33

Humans choose a step width that

Balances stability requirement

Energetic costs

During normal walking the ankle produces approximately _____% of total positive lower-extremity power.

50

A positive Trendelenburg sign is associated with ___________.

hip abductor weakness

During loading response the hip _____ act _____ to control contralateral pelvic drop. (frontal plane)

abductors, eccentrically