Kinetic and Kinematics Flashcards
3 methods of gait measurement
1) kinetics
2) kinematics
3) spatial temporal
2- D gait analysis is able to measure
- ROM
- GRF
- Power and moments
tools for 2 D gait analysis
- zynomat
- one camera
Zeno mat with protokinetics Software
- GAME lab 2 D analysis
- provides spatial-temporal output and kinematics
- visual video of foot prints
3 D motion capture is able to measure
- position
- velocity
- accelertion
- GRF
- joint moments
- powers
- both kinetics and kinematics
kinetics refers to
1) ground reaction forces
2) moments
3) power
ground reaction forces
external force
moments
- force to cause a rotation around a joint axis
- internal or external moments
power
- measured in watts
- force times time
- concentric vs eccentric
- 3 D gait analysis
internal moments are created by
contraction of the muscle, joint ligaments (restraint), and fascia/joint capsule (elastic properties)
- purpose is to counteract the external moments
- measures in newtons/ body weight
external moments are created by
landing on a surface (GRF)
in walking each joint creates a moment to either
1) stabilize and control
2) produce movement
extensor moments
support for body on surface
ex: gastroc/soleus, quads
flexor moments
pull away from the surface
ex: iliopsoas, DF
where in the gait cycle are GRF the most
LR and Heel off
power
energy/time
- greater power is created when it is performed in a shorter time
- measured in watts/joules per sec
concentric power
when power is created (positive)
eccentric power
when power is absorbed (negative)
when does the ankle produce the most concentric power
at push off
what type of power does the knee mostly do
eccentric power for absorbing GRF
hip flexors provide propulsive force during
pull off
where is the GRF at the ankle at IC
posterior
where is the GFR at the ankle at foot flat
posterior
