PHTY100 Lecture Notes - Lecture 10: Upper Limb, Muscle Contraction, Spinal Cord Injury
Gait: refers to the manner or style of walking
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Gait cycle: a fundamental unit to describe the gait during ambulation. This occurs from
the time when the heel of one foot strikes the ground to the time at which the heel of
the same foot contacts the ground again
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Stride length: the interval between 2 sequential initial floor contacts from the same limb
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Step length: the interval between an initial contact from one foot to the initial contact of
the other foot
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Stance phase: the entire period during which the foot is on the ground
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Swing phase: the time the foot is in the air
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Initial contact: the instant the foot makes contact with the ground
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Loading response: body weight transfer from initial contact through until the opposite
limb is lifted for swing
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Mid stance: initial phase of single leg support where momentum moves mass over
forefoot
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Terminal stance phase: completes single leg support. Body weight moves ahead of
forefoot
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Pre-swing phase: final phase of stance, represents functional commitment to initiating
forward motion prior to swing phase
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Initial swing phase: the lift off of the foot from the floor
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Mid swing phase: middle area of swing when foot is opposite the stance foot
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Terminal swing phase: last phase of swing in preparation for initial contact
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Heel strike: the onset of stance made by the contact of the heel onto the ground
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Toe off: the lift off of the big toe from contact point on the ground
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Ground reaction force (GRF): the force exerted by the ground on a body in contact with
it
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Terminology
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10. Gait
Monday, 22 May 2017
3:28 PM
ANAT101 Page 1
Moving across a surface
Walking
Cyclical - repetitious sequence of limb motions to move body forward
What is gait
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Stance - foot in contact with ground
Swing - no ground contact
Contains two main phases
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Characteristic unique to walking is the double stance phase
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Characteristic to running is double swing phase
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10.1 Define and describe the stance and swing phases of the human gait cycle
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Ranges from 30° flexion to 20° extension (total range 50°)
Hip motion allows pelvis and trunk to remain erect whilst body weight moves over
supporting foot.
Hip
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Ranges from approx. 60° flexion to 0° extension (total range 55° to 60°)
Key to stance stability
Reduces the length of the swinging limb and hence facilitates foot clearance in
swing phase- knee flexion
Knee
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Ranges from 20° plantarflexion to 5° dorsiflexion (total range 25°)
Plantarflexion reduces impact of heel contact at loading response.
Dorsiflexion through mid-stance to terminal stance facilitates advancement of
body weight over foot.
Plantarflexion prepares limb for swing phase by transforming extended knee into
Ankle
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10.2 Describe the range of motion of the lower limb joints during normal gait
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Plantarflexion prepares limb for swing phase by transforming extended knee into
freely flexing joint.
Dorsiflexion during swing allows for foot clearance
Contralateral gluteus medius and minimus (abductors) limit tilt during
stance phase
Tendency to tilt downward to the swing (non-supported) limb
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Movement (tilt) around an AP axis
Pelvis
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Reduces the amount of hip flexion needed
Anterior (forward) rotation over swinging limb
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At pelvis
Posterior (backward) over swinging limb
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Upper limb swings forward with contralateral lower limb
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At thorax and shoulder
Trunk
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Document Summary
Gait: refers to the manner or style of walking. Gait cycle: a fundamental unit to describe the gait during ambulation. This occurs from the time when the heel of one foot strikes the ground to the time at which the heel of the same foot contacts the ground again. Stride length: the interval between 2 sequential initial floor contacts from the same limb. Step length: the interval between an initial contact from one foot to the initial contact of the other foot. Stance phase: the entire period during which the foot is on the ground. Swing phase: the time the foot is in the air. Initial contact: the instant the foot makes contact with the ground. Loading response: body weight transfer from initial contact through until the opposite limb is lifted for swing. Mid stance: initial phase of single leg support where momentum moves mass over forefoot.
