wk 2 - gait cycle and temporal - spatial parameters Flashcards
1 step is
heel contact of one limb to heel contact of the opposite limb
1 stride is
heel contact of one limb to heel contact of the same limb (gait cycle)
what is the terminology of limbs when assessing gait
ipsilateral limb- usually one under investigation, initial contact limb
contralateral limb- the opposite leg
phase and event and their % of the gait cycle
initial contact (event)- 0% of cycle
loading response (period) 0-10%
opposite toe off (event) 10-12%
mid stance (period) 12-32%
heel rise (event) 32%
terminal stance (period) 32-50%
opposite initial contact (event) 50%
pre swing (period) 50-60%
toe off (event) 60-62%
initial swing (period) 62-77%
feet adjacent (event) 77%
mid swing (period) 77-86%
tibia vertical (event) 86%
terminal swing (period) 86-100%
terminal contact (event) 0%
initial contact what movements occur ?
hip- maximally flexed from end of swing phase (20deg) .
Knee- full extension from swing phase
ankle- dorsiflexed into a neutral and supinated position end of swing
loading response what is happening for the limb and what movements occur?
Limb accepts weight, Joints are flexing (controlled collapse) – this attenuates shock
Hip- begin to extend (moves from around 2o to 15 deg flexed)
knee- flexion to 15 degrees
ankle - plantarflexes to make ground contact (5 deg), pronation and internal tibial rotation occurs
opposite toe off what is happening
End of double support and the beginning of single support.
hip- extending (still in a flexed orientation)
knee-flexion
ankle- Plantarflexion causes forefoot to be flat, also pronated and internal tibial rotation have peaked.
mid stance what happens and movements that occur
Weight is fully accepted on stance limb (single support) Body progresses over stationary foot,
Hip- extension (neutral position, shifts into an extended orientation)
knee- begins to extend after peak stance phase flexion
ankle- dorsiflexion as tibia moves forward and supination- external rotation of tibia
heel rise and terminal stance what movements occur
hip- extension peak (orientated in extension)
knee- full extension peak
ankle- dorsiflexion peak after heel rise, supination- external tibial rotation
early heel lift can be a result of
a tight soleus (bouncy gait)
opposite initial contact what happens and what movements occur
The end of the period of single support and the second period of double support.
hip- flexion begins after reaching peak extension
knee- flexion after peak extension
ankle- plantarflexion (locking of mid tarsal joint as it weightbears), hind foot inversion and tibial external rotation
pre swing/toe off what happens
Limb is rapidly unloading, stance phase ends and swing begins.
hip- flexion
knee- flexion (30 degrees)
ankle- peak ankle plantarflexion after toe off (20 deg)
initial swing what movements occur
Hip- flexion
Knee- flexion 40-60 degrees assisted by the hip (passive)
ankle- begins to dorsiflex for ground clearance (still in plantarflexion orientation)
feet adjacent what happens and what movements
The swinging leg (ipsilateral) passes the stance leg (contralateral).
Hip- continues flexion (moving into flexed orientation)
knee- after early peak swing flexion (60 deg) passive extension begins (no muscular contraction, pendulum)
ankle- dorsiflexion for toe clearance
mid swing what happens
hip- flexion - moving to max flexion at 20 degrees
knee- passive extension - moving to full extension
ankle- dorsiflexion into neutral position
tibia vertical what movements occur
Hip- flexion ceases at 20 deg
knee- rapid, passive knee extension
Ankle- dorsiflexion to neutral
terminal swing what position is the body finished in
hip - flexion of 20 deg
knee- locked in full extension
ankle- neutral
double support periods take up how much % and why is that important
10% (20 for both initial and terminal)
more time in double than 20% flags that theyre dragging
what are temporal spatial parameters (4) and what are they used for? (3)
cycle time, cadence, stride length, and speed
these parameters give a guide to the walking ability of a subject but little specific information
-outcome measure
-performance measure
-or to normalise other gait measurements
methods to measure TSPs 4
- Measured manually
- Pedometer (steps)
- GAITRite mat (contact)
- Zebris treadmill
how to conduct TSP manually
required:
6-10m walkway
stopwatch
tape measure
markers for start and end point
to do:
count steps and record time taken to walk a given distance
calculate measurements based off data
formula for gait speed
speed (m/s) = distance (m) / time (s)
time to cover a set distance
forumla for cadence
cadence (steps/min) = total steps / duration of walk (s) x 60 seconds
number of steps per minute
cadence (steps/min) can be converted to (strides/sec) by dividing by 120
natural cadence is approx what?
120 steps/min
cycle time/ stride time formula
cycle time (s) = 120/cadence (steps/min)
time for one gait cycle completed
stride/step length formula
stride length = (distance covered / steps counted) X2
or
stride length = speed x cycle time
step length = distance covered / steps counted
key things about cadence and body type/age/gender (3)
-longer legs have lower cadence (pendulum)
-women tend to have slightly high cadence than men
-small children have higher cadence (shorter legs)
cadence does what with speed / limb length
linearly increases with speed
and decreases as limb length increases
angle of gait is what
toe in, toe out
abducted/externally rotated
or adducted (pigeon toed)
base of gait is what
step width/base of support
increases when balance is challenged
what can asymmetry in step length tell us ?
-limping (spending time off bad foot)
-bringing good foot to ground quicker (shortening swing phase and step length on the good side)
-short step length on one side means problems with single support on opposite side
-unequal limb lengths
what changes in the gait cycle when speed increases and decreases?
-double support time and stance phase decreases
-swing phase becomes longer
-when double support reaches 0 then running begins
decreases: balance compromised
normal values for speed, cadence and stride length
speed- 1.5m/s
cadence - 120 steps/min
stride length- 150cm (1.5m)
why is gait important with older generations
it is an indicator of clinical outcomes, daily living, risk of falls, quality of life, mobility, strength, etc
2 ways someone could increase their waking speed
increase cadence
increase stride length
what is normalisation
The process of removing variables such as height or weight from reporting on a
measurement
* Enables comparison between different populations
why is treadmill not the same as overground walking and indoor v outdoor
treadmill -
* Slower gait
* Shorter strides
* Less variable strides
* Keep in mind that treadmill walking is not representative of overground walking
same with walking outdoors vs indoors
-found walking outdoors resulted in faster gait with longer strides (p <.001) compared to other walking conditions.
things that affect TSP (5)
-gender (women have higher cadence/shorter stride length, narrower width)
-age
-pathology
-walking environment (treadmill, outdoors, indoors, ground)
-injury
