Gait

1
Gait
2
RLA - Gait Phases
3
Traditional Phases of Gait

• Stance Phase (60)
• Heel-strike (contact)
• Foot-flat
• Mid-stance point
• Heel-off
• Toe-off

4
Traditional Phases of Gait

• Swing Phase (40)
• Acceleration TO ? Acceleration
• Midswing Acceleration ? MSw
• Deceleration MSw ? Deceleration

5
Ranchos Los Amigos (RLA)

• Traditional references Reference Limb only
• RLA references both limbs
• RLA defines swing intervals more precisely

6
RLA Stance Phase

• 60 of Gait Cycle
• Loading Response (LR) 0 - 10 DS
• Midstance (MSt) 10 - 30
• Terminal Stance (TSt) 30-50
• Preswing (PSw) 50-60 DS

7
Instantaneous Events

• Initial Contact (IC)
• Toe-off (TO)

8
RLA Swing Phase

• 40 of Gait Cycle
• Initial Swing (Isw) 60 - 73
• Midswing (MSw) 73 - 87
• Terminal Swing (TSw) 87 - 100

9
Gait Phases
10
RLA

• Locomotor Unit
• Pelvis
• LE
• Passenger Unit
• HAT

11
Locomotor Functions

• Propulsion
• Stability
• Shock Absorption
• Energy Conservation
• lt 2 displacement

12
Task A Weight Acceptance

• IC
• LR
• IC ? opposite foot lifted (end of DS)
• 0 - 10

13
Task B Single Limb Support

• MSt (initiation of SLS)
• opposite foot lifted ? BW over forefoot
• 10 - 30
• TSt (completes SLS)
• Heel rise of RL ? IC of opposite limb
• 30 - 50

14
Task C Limb Advancement (Stance)

• PSw (initiation of second phase of DS)
• IC of opposite limb ? ipsilateral toe-off
• 50 - 60

15
Task C Limb Advancement (Swing)

• ISw
• Toe-off ? swing foot is opposite stance limb
• MSw
• Swing limb opposite stance limb ? swing limb
  tibia is vertical

16
Task C Limb Advancement (Swing)

• TSw
• vertical tibia ? IC

17
GRFV or Body Vector

• Effect of body weight
• HAT COG ? COP
• Relate GRFV to joint centers to determine
• magnitude and direction of joint instability

18
GRFV
HAT COG (T10)
GRFV
COP
19
GRFV
20
Moment

• External
• Internal

21
Ankle ROM
22
Ankle Moment
23
Knee ROM
24
Knee Moment
25
Hip ROM
26
Hip Moment
27
Rockers

• Heel
• Ankle
• Forefoot