Gait 3 Flashcards
How is kinetic energy of the falling COM converted into forward progression?
- Heel rocker
- Ankle rocker
- Forefoot rocker
(Closed kinetic chain function of muscles important in gait)
How does the heel rocker convert momentum of the falling COM into forward progression:
(3 step chain)
1) Hell acts as a fulcrum causing foot to plantar flex
2) Action of the pre-tibials ties the tibia to the falling foot
3) Action of the quadriceps ties the femur to the tibia no draws the body forward
Describe the ankle rocker mechanism:
- Ankle joint becomes the fulcrum
- Momentum of the tibia advances the body vector forward along the foot
- Controlled by soleus
Describe the forefoot rocker mechanism:
- Body vector progresses beyond metatarsal heads and heel rises
- Forward progression is accelerated as COM falls beyond BOS
Name the phases of stance and percentages:
Initial contact: 0 - 2%
Loading response: 0 - 10%
Mid stance: 10 - 30%
Terminal stance: 30 - 50%
Initial Contact -
Interval:
Event markers:
IC:
Interval: 0 - 2% of gait cycle
- The moment when the foot just touches the floor
Event markers:
Event 1: Initial Contact (IC)
- The first point of contact of the outstretched limb with the ground
Initial contact -
Objective:
Critical action:
IC
Objective:
- The limb is positioned to start the next stance phase
- The foot is positioned to utilise the heel rocker
Critical Action:
- Heel first contact
Loading response:
Interval:
Event markers:
LR:
Interval: 0 - 10% of gait
- Begins with the initial floor contact and continues until the other foot is lifted for swing
Event markers:
- E1: Initial contact (IC)
- E2: Opposite toe off (OT)
Loading response:
Objectives:
Critical actions:
LR
Objectives:
- Shock absorption
- Weight bearing stability
- Preservation of forward progression
Critical actions:
- Hip stability
- Controlled knee flexion and plantar flexion
Mid stance
Interval:
Event markers:
Interval: 10 - 30% of gait cycle
- Begins as the other foot is lifted and continues until body weight is aligned over the forefoot
Event makers:
- E2 Opposite toe off (OT)
- E3 Heel rise (HR) opposite foot adjacent
Terminal Stance
Interval:
Event Markers:
Interval: 30 - 50% of gait cycle
- Begins with heel rise and continues until the other foot strikes the ground
Event markers
E3: Heel rise (HR)
E4: Opposite Initial contact
Terminal stance
Objective:
Critical actions
Terminal Stance
Objective: progression of the body beyond the supporting foot
Critical Actions:
- Ankle locked in dorsiflexion with heel rise (forefoot rocker)
- Stance limb trails behind
Pre Swing
Interval:
Event markers:
Pre Swing
Interval: 50 - 60% of gait cycle
- Begins with initial contact of opposite limb and ends with ipsilateral toe-off
Event markers:
- E4: Opposite initial contact
- E5: Toe off (TO)
Pre-Swing
Objective:
Critical Action:
Pre-Swing
Objective: Position the limb for swing
Critical Action: Passive knee flexion to 40 degrees
