Gait Intro Flashcards
Side to Side COM Oscillations
-Max position of COM to either side occurs at midpoint of stance phase
-about 4cm
-increases as width of BOS increases
Vertical COM Oscillations
-goes from up and down during gait
-minimum height of COM occurs at midpoint of double limb
-maximum height of COM occurs at midpoint of single-limb
about 5 cm of displacements
Stride is also known
1 gait cycle
1 gait cycle is equivalent to…
heel strike of 1 foot to heel strike of same foot
Stance Phase Components
Initial Contact
Loading Response
Midstance
Terminal Stance
Pre-Swing
Swing Phase Components
Initial Swing
Mid-Swing
Terminal Swing
When is the leg in single support?
occurs 80% of the gait cycle
- Stance Phase
a. Midstance
b. Terminal Stance - Swing Phase
a. Initial Swing
b. Mid-Swing
c. Terminal Swing
When is the leg in double limb support?
occurs 20% of the gait cycle
- Stance Phase
a. Initial Contact
b. Loading Response
c. Pre-Swing
Initial Contact
event, not a phase, that defines the beginning of gait cycle
stance phase, double limb support
Loading Response
begins with initial contact and ends with contralateral toe off, when the opposite extremity leaves the ground
stance phase, double limb support
Midstance
begins with contralateral toe off and ends with the center of gravity is directly over the reference foot
stance phase, single support
Terminal Stance
begins when the center of gravity is over the supporting foot and ends when the contralateral foot contacts the ground. during terminal stance, the heel rises from the ground
stance phase, single limb support
Pre-Swing
begins at contralateral initial contact and ends at toe off, at around 60% of the gait cycle
stance phase
double limb support
Initial Swing
begins at toe off and continues until maximum knee flexion occurs
swing phase, single support
Mid-Swing
period from maximum knee flexion until the tibia is vertical or perpendicular to the ground
swing phase, single support
Terminal Swing
begins where the tibia is vertical and ends at initial contact
Swing phase, single leg support
Step Length
heel strike on 1 side to heel strike on opposite side
Stride length
equivalent to right step + left step (1 gait cycle)
stride starts and ends with the same foot
Step Width
lateral distance between heel centers of two successive foot contacts
Foot Angle
also known as foot progression
amount of toe-out or toe-in relative direction of movement
Cadence
number of steps per minute
known as step rate
Stride Time
time for the full gait cycle
Walking Speed
distance covered/unit time
Base of support
area beneath person that includes every point of contact that the person makes with the supporting surface
Changes to base of support
wider steps = unstable gait
Smaller steps = instability
When your center of mass exceeds your BOS…
you become unstable and are increased risk of falling
Parts of Kinematic Graphs
1.Angle at Initial Contact
2.Peak Angle
3.Angle at Toe-Off
4.Angular Excursion
Angle at initial contact
ALWAYS first point on graph
Peak Angle
most extreme point of graph (both positive and negative)
Angle at Toe-Off
last data point or last point @ 60% when the graph is the full gait cycle
Angular Excursion
Total ROM the joint moves in a specific direction
Sagittal Plane Ankle, Phases of Stance
IC: 0-5 of PF
Early LR: slight PF
LR/Mid: DF of 10
Terminal: PF 15-20
Heel Rocker
initial contact until foot is flat
heel is rocking the most
Ankle rocker
loading response/mid-stance
ankle is rocking the most
Forefoot rocker
terminal stance/toe off
forefoot rotating the most
Stance Phase Knee Kinematics
IC = 5 flex
LR: flexes before extending
Mid: extends until heel-off
Terminal: flexed through swing
Toe: knee flexed to 30
Sagittal Pelvis Kinematics
-Pelvis will alternate between post and ant tilt
-IC = neutral
-LR = posterior tilt
-Mid = anterior tilt
-Terminal = posterior tilt
amount of tilt increases with speed of ambulation
Stance Phase Kinematics, Hip
IC = 30 flexion
Later LR/Mid/Terminal = 10 extension
Late terminal = hip flexes
Toe off = neutral
Frontal Plane Pelvis
IC = pelvis at neutral
LR = pelvic drop
Mid = pelvic rise
Measuring the distance a patient covers during one gait cycle would be the same as measuring ______ length.
stride
This sub-phase occurs during the second period of double support
Pre-swing
The stance limb is generally flat on the ground during this entire sub-phase
Midstance
This sub-phase occurs during the first period of double support
Loading Response
The heel begins to rise off the ground during this sub-phase
Terminal Stance
Generally considered an event and not a sub-phase; begins the gait cycle
Initial Contact
During gait, heel strike of the right foot until heel strike of the left foot is called a
left step
T/F: Step width is measured as the shortest diagnonal distance between heel centers of two successive foot contacts.
False
What would likely not contribute to a dorsiflexion (i.e. ankle rocker) restriction during walking?
Anterior talofibular ligament
Which “rocker” at the ankle joint generally occurs during the loading response only - not during any other stance sub-phase?
Heel rocker
Peak knee flexion during the gait cycle occurs at the end of
Initial swing
For a patient who has limited hip extension during gait, the most likely compensation at the trunk and pelvis would be
Increased anterior pelvic tilt and lumbar lordosis during hip extension
Ankle eversion is best measured from which view during a 2D video gait analysis?
Posterior view
