Gait
■ Gait cycle
cycle division
1. gait cycle; 2 periods, stance & swing
stance - entire period during which the foot is on the ground,
initial contact으로 시작
swing - time that the foot is in the air for limb advancement,
toe-off부터 시작
2. stance; 3 intervals according to the sequence of floor contact by the two feet
① initial double stance
② single limb support - single stance의 duration이 limb`s support capability의 best index
③ terminal double stance
3. timing
stance 60% - 10%, 40%, 10%
swing 40%
- both feet가 limbs의 support roles을 바꾸는 동안 ground와 contact하는 interval을 가지는 것이 walking의 basic 특성이다.
- double stance가 빠지면 → running mode of locomotion으로 들어감
stride & step
stride; interval between two sequential initial floor contacts by the same limb
step; interval between an initial contact by each foot
■ Phase of gait
division of gait cycle
Task A. weight acceptance
phase 1 - initial contact
목적; limb…(생략)
|
치
; responsible only for its own
postural integrity
; 70% of body weight
; center of gravity (C/G)
- locomotor unit; 2 lower limbs & pelvis
; 11개의 joints가 포함
(LS and both hips, knees, ankles, subtalars and metatarsophalangeal)
-pelvis는 passenger unit와 locomotion
system의 dual part로 작용
; 2 lower limbs을 연결시키는mobile
link와 hip joints에 ride한 passenger
unit의 bottom segment 역할
2. locomotor functions; 4가지
1) a propulsive force is generated (propulsion)
2) upright stability is maintained, despite an ever-changing posture (stance stability)
3) the shock of floor impact at the onset of each stride is minimized (shock absorption)
4) energy is conserved by these functions being performed in a manner that reduces the amount of muscular effort required (energy conservation)
1) standing stability
- body weight vector
; body weight의 instantaneous alignment (vertical line)는 foot plate (floor weight)에 의해 감지되는 ground reaction forces (GRF