TEC1 - Semester 2: Gait Biomechanics Flashcards
What are purposes of arches of the foot?
- adapting to uneven surfaces
- provides traction for movement
- leverage for propulsion
- awareness of joint and body position for balance
Which movements are required during gait?
dorsiflexion & plantarflexion, flexion & extension of toes, inversion & eversion, abduction & adduction
Describe dorsiflexion and plantarflexion.
- in sagittal plane, around coronal axis
- dorsiflexion: decreases angle between leg and dorsum of foot
- plantarflexion: increases angle between leg and dorsum of foot
Plane and AOR of the toes?
sagittal plane, coronal axis
Describe inversion and eversion.
- frontal plane, longitudinal axis
- inversion: plantar surface brought toward midline
- eversion: plantar surface brought away from midline
Describe adduction and abduction.
- transverse plane, vertical axis
- abduction: distal aspect of foot moves away from midline
- adduction: opposite
What is pronation?
motion in all three planes. includes eversion, dorsiflexion and abduction
What happens in non weight bearing pronation?
calcaneal eversion, abduction and dorsiflexion
What happens in weight bearing pronation?
calcaneal eversion, talar adduction & plantaflexion, tib-fib medial rotation
What is supination?
also a motion in all three planes. includes inversion, plantarflexion and adduction
What happens in non weight bearing supination?
calcaneal inversion, adduction and plantarflexion
what happens in weight bearing supination?
calcaneal inversion, talar abduction & dorsiflexion, tib-fib lateral rotation
Which factors contribute to overpronation?
- tibialis posterior weakness
- flat feet
- genu valgum (knock knees)
- subtalar eversion
- obesity
What are the 4 major criteria essential for walking?
equilibrium, locomotion, musculoskeletal integrity and neurological control
Describe what the 4 criteria mean.
Equilibrium: ability to assume upright posture and maintain balance
Locomotion: ability to iniate and maintain rhythmic stepping
Musculoskeletal integrity: normal bone, joint and muscle function
Neurological control: neurons must receive and send messages to tell the body how and when to move
Define “gait”.
series of rhythmical, alternating movements of trunk and limbs resulting in forward progression of the body
What is the gait cycle?
- single sequence of functions by ONE limb
- begins when reference foot contacts ground
- ends with subsequent floor contact of same foot
What is the step length?
Distance between points of heel contact of opposite feet (in normal gait, right and left are same)
What is the stride length?
distance between points of heel contact of same foot (in normal gait: double step length)
What is the walking base?
side-to-side distance between line of two feet
What are cadence and velocity?
cadence: number of steps per minute
velocity: distance covered in a certain amount of time (m/s)
Describe stance and swing phase.
Stance phase: reference limb is in contact with floor (60%)
Swing phase: reference limb not in contact with floor (40%)
What are the five steps in stance phase?
- heel strike
- flat foot
- midstance
- heel lift
- toe off
Describe the heel strike.
- heel of leading leg strikes ground
- foot: supinated, ankle: dorsiflexed, knee: extended, hip: flexed & ant. rotated, pelvis: contralaterally rotated, shoulders: extended
Describe flat foot?
- first instant when foot is flat on ground
- foor: neutral, ankle: neutral, knee: slightly flexed
Describe midstance.
- weight is directly over supporting lower extremity
- begins after flat foot ends with heel off
- foot: slight pronation, ankle: neutral, knee: fully extended, hip: neutral, pelvis: neutral, shoulders: neutral
Describe heel off.
- heel of reference foot leaves the ground
- foot: slight pronation, ankle: DF to PF, knee: fully extended, hip: fully extended, pelvis: right rotation, shoulder: slightly flexed
Describe toe off
- toe of the reference foot leaves ground
- foot: neutral, ankle: PF, knee: fully extended, hip: fully extended, pelvis: right rotation, shoulder: flexed
What are the steps of the swing phase?
Acceleration, midswing, deceleration
Describe acceleration.
- as toe leaves ground and continues until midswing; swinging leg is directly under body
- foot: neutral, ankle: neutral, knee: slightly flexed, hip: fully extended & int. rotated, pelvis: right rotation, shoulder: flexed
Describe midswing.
- when leg passes directly beneath body
- foot: neutral, ankle: slight DF and toe flexion, knee: flexed, hip: neutral, pelvis: neutral, shoulder: neutral
Describe deceleration.
- when limb is decelerating in preparation for heel strike
- foot: slight supination, ankle: DF, knee: fully extended, hip: flexed & external rotation, pelvis: rotated left, shoulder: extended
