Gait Flashcards
1
Q
what is gait?
A
- mechanism by which the body is transported using co-ordinated movement of major lower limb joints.
2
Q
what are the 2 phases of gait?
A
- stance : when foot is in contact with the ground.
- swing : when foot is not in contact with the ground.
60: 40 usually.
3
Q
what are 5 important attributes needed for normal gait?
A
- stability in stance : ability to stand on one leg until weight transferred from one leg to another.
- foot clearance : raise foot off ground at swing.
- pre-position for next phase.
- adequate length of step for next stance.
- energy conservation : energy efficient.
4
Q
what is double support in gait?
A
- two periods within normal gait cycle where both feet are in contact with the ground.
- faster you walk, jog or run the period of double support decreases.
5
Q
what is double float in gait?
A
- a moment in gait where neither feet are in contact with the ground, usually in running or sprinting.
- faster you run the longer the double float.
6
Q
what happens to the stance swing ratio in sprinting?
A
essentially reverses so stance is only 40% and swing phase is 60%.
7
Q
what are the subdivisions of stance phase?
A
- initial contact : heel strike.
- loading response : shock of impact absorbed by knee and ankle joint. rocks forward on heel.
- mid-stance: foot flat and ready for forward propulsion.
- terminal stance : ankle plantar-flexed heel of other leg off ground.
- pre-swing : metatarsophalangeal joints push off on toes.
8
Q
what are the subdivision of the swing phase?
A
- initial swing : knee flexes to enable foot to clear ground.
- mid swing : hip flexes and pelvis swings to move forward and dorsiflexion of ankle to neutral position.
- terminal swing : knee extends, foot closer to ground for next heel strike.
9
Q
define stride.
A
- distance from initial contact with one leg to the next initial contact with same leg.
10
Q
define step.
A
- distance of initial contact with one leg to the initial contact with opposite leg.
2 STEPS IN STRIDE.
11
Q
define cadence.
A
- number of steps per minute.
12
Q
differentiate between kinematics and kinetics in gait.
A
- kinematics mean motions themselves like joint angles whereas kinetics is the force and moments that cause the motion.
13
Q
how do muscles conribute to the kinetics.
A
- by producing force to provide stability opposing gravity.
- propel body segments forward through controlled movements of joints.
14
Q
can you describe the roles played by muscles in the stance phase.
A
- during initial contact the anterior compartment muscles like tibialis anterior (dorsiflexor of ankle) contracts and lengthens so foot doesn’t slap ground.
- midstance tibialis relaxes.
- terminal stance the posterior compartment muscles like gastrocnemius and soleus take over and plantar-flexes ankle.
15
Q
how is energy conserved at gait?
A
- minimise excursion of centre of gravity of body.
- control momentum by eccentric contraction.
- transferring energy between body segments using ligaments, tendons etc.
- using muscles intermittently between stance and swing.
