Normal Gait Flashcards
What phase makes up ~60% of the gait cycle?
Stance Phase
What phase makes up ~40% of the gait cycle?
Swing Phase
What 4 subphases make up Stance Phase?
- Initial Contact (IC)
- Loading Response (LR)
- Midstance (MSt)
- Terminal Stance (TSt)
What 4 subphases make up Swing Phase?
- Pre Swing (PSw)
- Initial Swing (ISw)
- Mid Swing (MSw)
- Terminal Swing (TSw)
What are the 3 functional tasks of gait?
- Weight Acceptance
- Single Limb Support
- Swing limb advancement
What subphases make up the functional task of Weight Acceptance? What are characteristics of this functional task?
IC and LR
forward progression, stability, shock absorption
What subphases make up the functional task of Single Limb Support? What are characteristics of this functional task?
MSt and TSt
Forward progression, stability
What subphases make up the functional task of Swing Limb Advancement? What are characteristics of this functional task?
PSw, ISw, MSw, TSw
Foot clearance, limb advancement
What are the 4 biomechanical subcomponents of gait?
moving away from an impairment-based model –> function-based approach for treating gait
- Stance Control
- Limb Advancement
- Propulsion
- Postural Stability
Which subcomponent does this describe:
“absence of vertical limb or trunk collapse during stance”?
Stance Control
Which subcomponent does this describe:
“adequate foot clearance and a positive step length bilaterally”?
Limb Advancement
Which subcomponent does this describe:
“ability to move center of mass in a specific direction (forward, backward, etc.) during stance, separate from limb advancement”?
Propulsion
Which subcomponent does this describe:
“maintaining upright in sagittal and frontal planes, keeping center of mass within base of support”?
Postural Stability
Which rockers are for deceleration
- heel rocker
- ankle rocker
Which rockers are for acceleration?
- forefoot rocker
- toe rocker
In Initial Contact, what position is the ankle in? What’s the muscle activity?
Neutral
* Muscle activity: isometric pre-tibials
In Initial contact, what is the knee doing? What’s the muscle activity?
5 degrees of flexion AKA “neutral soft knee”
* Muscle activity: quadriceps (preparation for LR)
In Initial Contact, what is the hip doing? What is the muscle activity?
20 degrees hip flexion
* GRF anterior to hip
* Muscle Activity: hip extensors to stabilize the thigh during LR
What is the critical event of Initial Contact?
Heel first contact
What is the ankle doing in Loading Response? What is the muscle activity? What rocker is here?
5 degrees PF
* Muscle activity: eccentric pre-tibials
* Heel rocker
What is the knee doing in LR? What is the muscle activity?
15 degrees flexion (from 5 degrees in IC)
* Muscle Activity: eccentric quadriceps
What is the hip doing in LR? What is the muscle activity?
20 degrees flexion (same as before)
* Muscle activity: hip extensors/abductors
What is the critical event in LR?
- Hip stability
- Controlled knee flexion
- Ankle PF (heel rocker)
Where are GRF in LR compared to IC?
In IC, they are both anterior to knee and hip
In LR, GRF is anterior to hip, posterior to knee
What signals the beginning of MidStance?
Once we go from double leg support to single limb support = start of MSt
What is the ankle doing in Midstance? What is the muscle activity? What is the rocker here?
5 degrees DF (from 5 deg PF in LR)
* Muscle Activity: eccentric plantarflexors
* Ankle rocker
What is the knee doing in midstance? What is the muscle activity?
5 degrees flexion (from 15 degrees in LR)
* Muscle Activity: quads intially then off
What is the hip doing in midstance? What is the muscle activity?
Neutral (from 20 deg flexion in LR)
* Muscle activity: hip abductors
What is the critical event in Midstance?
Controlled tibial advancement
What are the toes doing in terminal stance?
20-30 degrees extension
What is the ankle doing in terminal stance? What is the muscle activity? What is the rocker?
10 degrees DF (from 5 deg DF in MSt)
* Muscle activity: eccentric PF
* Forefoot rocker
What are the knees doing in TSt? What is the muscle activity?
5 degrees flexion (neutral)
* Muscle activity: NONE
What are the hips doing in TSt? What is the muscle activity?
20 degrees extension (from neutral in MSt)
* Muscle Activity: NONE
What signifies the end of Terminal Stance?
Opposite foot’s heel touches the ground
What is the critical event of Terminal Stance?
- Calf muscles control ankle DF allowing heel rise
- Trailing limb
In what phase could we see hip drop?
Midstance
When do we commonly see knee hyperextension thrust?
Loading Response
Midstance
When do we see the highest torque demand on the ankle?
Terminal Stance
What is the hallmark of Terminal Stance?
the upside down “V”
What is happening at the toes in preswing? What is the rocker?
55-60 degrees extension (from 20-30 degrees in TSt)
* Toe rocker
What is happening at the ankle in Preswing? What is the muscle activity?
15 degrees PF (from 10 degrees DF)
* muscle activity: NONE
What is happening at the knee in Preswing? What is the muscle activity?
40 degrees flexion (from 5 degrees flexion)
* Muscle activity: NONE
* If no big V in TSt, then no KF in this phase
What is happening at the hip in Preswing? What is the muscle activity?
10 degrees extension (from 20 degrees ext. in TSt)
* Muscle activity: adductors
Is everything passive or active in Preswing?
passive
What is the critical event in Preswing?
- Passive knee flexion
- Ankle PF assists with passive knee flexion
What is happening at the ankle in Initial Swing? What is the muscle activity?
5 degrees PF (From 15 deg PF in PSw)
* Muscle activity: pre-tibials concentrically
What is happening at the knee in Initial Swing? What is the muscle activity?
60 degrees flexion (from 40 deg in PSw)
* Muscle activity: knee flexors
What is happening at the hip in Initial Swing? What is the muscle activity?
15 degrees flexion (from 10 deg ext in PSw)
* Muscle activity: concentric hip flexors
What is the critical event of Initial Swing?
- Hip flexion 15 degrees
- Knee flexion to 60 degrees
What is happening at the ankles in Midswing? What is the muscle activity?
Neutral (from 5 deg PF)
* Muscle Activity: isometric pre-tibials
What is happening at the knee in midswing? What is the muscle activity?
25 degrees flexion (from 60 deg in ISw)
* Muscle activity: silent then hamstring initiate to eccentrically decelerate the lower limb
What is happening at the hip in midswing? What is the muscle activity?
25 degrees flexion (from 15 deg in ISw)
* Muscle activity: concentric hip flexors initially them hamstrings eccentrically
What is the critical event in midswing?
- Further hip flexion
- DF to neutral
What is happening at the ankles in Terminal Swing? What is the muscle activity?
Neutral
* Muscle activity: isometric pre-tibials
What is happening at the knee in terminal swing? What is the muscle activity?
Neutral (5 degrees - from 25 degrees in MSw)
* Muscle activity: quadriceps concentrically; hamstrings eccentrically decelerate the lower limb
What is happening at the hip in Terminal Swing? What is the muscle activity?
20 degrees flexion (from 25 deg in MSw)
* Muscle activity: hamstrings eccentrically decelerate the lower limb
What is the critical event in Terminal Swing?
Knee extension
What happens if there is no Knee extension in Terminal Swing?
Foot flat or knee bent in IC
What are the 4 major causes of pathological gait?
- abnormal joint ROM
- impaired motor control
- impaired sensation
- pain
In LR, if we don’t have the critical event of ankle PF, what might you see instead?
- foot drop
- forefoot contact
If we don’t see the critical event of “calf muscles control ankle DF allowing heel rise” in Terminal Stance, what might we see?
short shuffle step / avoidance of TSt
What gait phase requires 60 degrees of toe ext
preswing
what gait phase has the critical event of a neutral ankle
mid swing
which gait phase has the critical event of passive knee flexion
pre-swing
which gait phase has the critical event of Calf muscles controlling DF to allow heel rise + trailing limb
terminal stance
which gait phase has the critical event of 60 degrees of knee flexion and 15 degrees of hip flexion
initial swing
Which gait phase has the critical event of controlled tibial advancement
mid stance
Which gait phases include eccentric control by the hamstrings
midswing
terminal swing
which gait phase includes the critical event of: hip stability, controlled knee flexion, and PF control of the heel rocker
loading response
What muscles assist with knee flexion during pre swing
calves
What gait phase do you see the big upside down V?
terminal stance