GAIT Flashcards
WK 8
What is gait?
- style of walking
- repitious sequence of limbs to move the body forward
stance: 60%GC (foot in contact w ground)
swing: 40%GC (foot X in contact w ground)
gait cycle
Stance Phase
foot in contact w the ground, 60%GC
1. IC:
- first moment foot touchs ground
2: Load Response:
- BW transfers to stance leg until other leg begins to swing
3. Midstance:
- BW moves over stance leg in SS
4. Terminal Stance:
- end of SS
- BW shifts infront of forefoot
- prepare for push off
5. Pre-Swing phase:
- final stance phase
- prepare for swing
- forward motion
gait cycle
Swing
foot NOT in contact w ground, 40%GC
1. inital swing:
- start swing
- foot off ground
2. mid swing:
- foot passes next to stance foot
3. end swing:
- prepares for IC
gait cycle - terminology
Stride length
Step length
1. Stride length:
- distance bw 2 heel strikes of same foot
2. Step length:
- distance bw 2 heel strikes of opposite foot
gait cycle - terminology
Heel stike & Toe off
Heel strike:
- heel contacts the ground
Toe off:
- big toe lifts the ground
gait cycle - terminology
Gait and Gait Cycle
Gait:
- style of walking
Gait cycle:
- one full cycle from hel strike of one foot to the next heel strike of the same foot
gait cycle - terminology
Ground Reaction Force (GRF)
- force the ground exerts back on the body during contact
Centre of Gravity
What is CoG
- concentration of BW
- static anatomical position: anterior to vertebral S2
- ⬆️est = midstance
Centre of Gravity
Why is it important to limit CoG?
- minimise energy expenditure
- limit wear + tear of muscles
Centre of Gravity
Factors limiting movements of CoG
Vertical movements of CoG:
1. stance:
- inversion / eversion
- limits inf and sup movem of CoG
2. late stance:
- plantarflex
- limits inf movem of CoG
3. swing phase:
- A pelvic tilt
- limits inf movem of CoG
4. support phase:
- knee flex
- limits sup movem of CoG
5. swing phase:
- A pelvic tilt
- knee flex @ early swing
- limits sup movem of CoG
What are the muscles doing during gait?
- prod movement req for locomotion
- accel/decel body parts
- stabilise body parts for efficient movement
GC
HIP
- 30º flex
- 20º ext
- total range 50º
- pelvis + trunk = erect
- BW moves over supporting foot
GC
KNEE
- 60º flex
- 0º ext
- 55-60º total range
- ⬇️ length of swing length so foot clearence can occur
GC
ANKLE
- 20º plantar
- 5º dorsi
- 25º total range
Plantarflexion:
1. LR -> DCR impact of HC
3. prep limb for swing phase ->
(extends knee into freely flexing jiont)
Dorsiflexion:
2. midstance to terminal stance ->
facil adv of BW over foot
4. swing ->
foot clearence
GC
Pelvic motion - coronal & sagittal
Coronal (front view)
movement:
- abd / add, lift / drop
axis:
- AP
walking:
- drop on swing leg ( X contact )
pelvic drop:
- Gmed + min on opp (stance) leg activate to stablise pelvis
failure:
- Trendelenburg gait = noticeable hip drop due to ppoor hip abd on stance leg
Sagittal (side view):
movement:
- 2-4º tilt
axis:
- transverse
GC
Initial contact
funciton:
- pos limb for stance pos
GC
Loading Response
funciton:
- shock absorb
- weight acceptance
GC
Mid Stance
funciton:
- stability
- progression over foot
GC
Terminal Stance
function:
- progression of body beyonf supporting foot
GC
Pre-swing
function:
- pos limb for swing phase
GC
Initial Swing
function:
- foot clearence
- advance limb
GC
Mid-swing
function:
- foot clearence
- adv limb
GC
Terminal-swing
function:
- complete advancement
- prepare for new gait cycle
