Normal Gait Flashcards
Velocity
82 m/min, 1.2-1.4 m/s, 2.7-3.1 mph
Cadence
113-116 steps/min
Base of Support Norms
-2-4 inches
Toe Out Norms
7 degrees
Stance Phase
62%
Swing Phase
38%
Single Limb
80%
Double Limb Support
20%
Tasks of Gait
- Maintain HAT
- Maintain balance/posture
- Control Feet
- Generate forward velocity
- Shock absorption to decrease velocity
Gait Cycle
Stance:
-Initial contact (Preswing): heel contact, flexion hip (20), ant pelvic rotation
-Loading response (pre- swing): weightshift, flexed knee (15), DF (lack of will show)
-Midstance (initial-mid Swing): Neutral hip
-Terminal Stance (Terminal Swing): extended hip (20), DF (10 at highest), mtp exetnsion
-Pre-Swing (Initial contact and loading response): extension, flexion (40), PF (15 most) (MTP 60 for windlass)
Swing:
-Initial Swing (midstance): toe off, most knee flexion (60),
-Middle Swing (Midstance): most flexion (25)
-Terminal Swing (Terminal Stance): right before initial contact
Ground Reaction Forces
IC: Ant to hip and knee, post to ankle
LR: Post to ankle and knee, ant to hip
MS: Ant to ankle and knee, post to hip
TS: Ant to ankle and knee, post to hip
PS: Post to hip and knee, an to ankle
Internal Moments
-counteract external forces (eccentric or concentric to balance forces)
IC: ankle DF, hip ext, knee flex
LR: ankle DF, hip ext, knee ext
MS: ankle PF, hip flx, knee flex
TS: ankle PF, hip flx, knee flex
PS: ankle PF, hip flx, knee ext
Rockers
- Heel (IC, LR): Deceleration
- Ankle (MS): Deceleration
- Foefoot (TS): Aceleration
- Toes (PS): Aceleration
Weight Acceptance (aspects)
-beginning
-Initial contact and loading response
-progression, stability, shock absorption
Single Limb Support (aspects)
-midstance and terminal stance
-forward progression, stability
Swing Limb Advancement (aspects)
-preswing, initial swing, midswing, terminal swing
-foot clearance, limb advancement
Stance Phase Components
-initial contact
-loading response
-Mid-stance
-terminal stance
Swing Phase Components
-Preswing
-Initial swing
-Mid swing
-Terminal swing
Biomechanical Subcomponents of Gait: Stance Control
-absence of vertical limb or trunk collapse
Biomechanical Subcomponents of Gait: Limb Advancement
-adequate foot clearance and positive step length bilaterally
Biomechanical Subcomponents of Gait: Propulsion
-ability to move center of mass in a specific direction
Biomechanical Subcomponents of Gait: Postural Stability
-maintaining upright sagittal and frontal planes w/in BOS
Initial Contact
Critical Event: Heel first contact
-GRF anterior
Ankle:
-neutral
-Isometric ant tib
Knee:
-Neutral/ 5 deg flx (soft knee)
-Concentric of quad to prep for LR
Hip:
-20deg of flx (stabilize from GRF)
-Hip extensors (counter hip flx from GRF)
Loading Response
Critical Event: Hip stability, controlled knee flx, ankle PF
-GRF anterior, post to knee
Ankle:
-5 deg PF
-eccentric ant tib
-Heel rocker
Knee:
-15 deg flx
-Eccentric of quad to prep
Hip:
-20 deg of flx (stabilize from GRF)
-Hip extensors (counter hip flx from GRF) and adductors to bring LE in
Midstance
Critical Event: Controlled tibial advancement
-GRF underneath
Ankle:
-5 deg DF
-eccentric plantarflexors (tibial incline)
-Ankle rocker
Knee:
-5 deg flx
-Initial quad, then turn off
Hip:
-Neutral
-Hip extensors (counter hip flx from GRF) and abductors to bring LE in
Terminal Stance
Critical Event: Calf muscles control DF allowing heel raise; trailing limb
-GRF ANT to knee; POST to hip
-Big āVā
-Highest torque demand
Toes:
-20-30 deg ext (windlass propulsion)
Ankle:
-10 deg DF (most)
-eccentric plantarflexors (tibial incline)
-Forefoot rocker
Knee:
-5 deg flx (neutral)
-no muscles
Hip:
-20 deg ext (most)
-No muscles
Pelvis:
-5 deg backwards rotation
Preswing
Critical Event: Passive knee flexion; PFs assist with knee flexion
-passive phase
-CONTRA leg contact drives leg forward
Toes:
-55-60 deg ext
-toe rocker
Ankle:
-15 deg PF (most)
-no muscle activity; relaxed from DF
Knee:
-40 deg flx passive
-No muscles
Hip:
-10 deg ext
-Hip adductors to bring LE in
Initial Swing
Critical Event: Hip flexion; knee flexion
Ankle:
-5 deg PF
-Anterior tib contraction
Knee:
-60 deg flx (most)
-Knee flexors; assisted by hip flexors
Hip:
-15 def flx
-Hip flexors
Mid-Swing
Critical Event: More hip flx; ankle neutral
Ankle:
-Neutral
-Anterior tib isometric
Knee:
-25 deg flx
-Hamstrings to eccentrically decelerate limb
Hip:
-25 deg flx (most)
-Hip flexors concentrically; Hamstrings eccentrically
Terminal Swing
Critical Event: Knee extension
Ankle:
-Neutral
-isometric ant tib
Knee:
-5 deg flx (neutral)
-Quads concentric; hamstrings eccentric to decelerate
Hip:
-20 deg flx
-Hamstrings to decelerate limb
Most Toe Extension
-Preswing
-55-60 deg
Most Dorsiflexion
-Terminal Stance
-10 deg
Most Plantar Flexion
-Preswing
-15 deg
Most Knee Flexion
-Initial swing
-60 deg
Most Knee Extension
-Midstance
Most Hip Flexion
-Mid-swing
-25 deg
Most Hip Extension
-Terminal stance
-20 deg
Physics: Initial Contact
-GFR behind ankle: PF moment (controlled by Ant tib)
-GFR infront of knee: knee ext moment
-GFR in front of hip: hip flx moment
Physics: Loading Response
GFR post to ankle: PF moment (controlled by Ant tib)
GFR post to knee: knee flx moment (controlled by quads)
GFR ant to hip: hip flx moment (controlled by glute max)
Physics: Midstance
EARLY:
GFR ant to ankle: DF moment (controlled by soleus to slow down tibial advancement)
GFR post to knee (but closer): knee flx moment (controlled by quads)
GFR post to hip: hip ext moment
LATE:
GFR ant to ankle: DF moment (controlled by soleus); drives heel rise
GFR ant to knee: knee ext moment (muscles off)
GFR post to hip: hip ext moment (muscles off)
Physics: Terminal Stance
GFR ant to ankle: DF moment (controlled by Ant tib); heel rise
GFR post to knee: early knee flx moment; after passive flx (controlled by gastroc)
GFR post to hip: hip ext moment (controlled by glute max)
