Flashcards in Gait Deck (18)
What is gait?
- mechanism by which the body is transported using coordinated movements of the major lower limb joints
- via energy-efficient interactions of MSK and neurological systems
What is the gait cycle?
period of time from initial contact of foot to next initial contact on the same side (i.e. full revolution of 1 limb)
What are the 2 phases of the gait cycle?
- stance phase (60%) - foot contacts floor
- swing phase (40%) - foot has no contact with floor
What is the difference between running and walking?
- Walking: there is a period of double support where the stance phases of the 2 limbs overlap.
- Running: there is a period of double float where the swing phases of the limbs overlap.
Name the stages of the stance phase.
1. initial contact (heel strike)
2. loading response
3. mid-stance (foot flat)
4. terminal stance (heel off)
5. pre-swing (toe off)
Which muscles are involved in the initial contact stage?
i) gluteus maximus - acts on hip to decelerate lower limb
ii) quadriceps femoris - keeps leg extended at knee and hip
iii) anterior leg compartment - maintains ankle dorsiflexion, positioning heel for strike
Which muscles are involved in the mid-stance and terminal stance (support stage)?
i) quadriceps femoris - keeps leg extended, accepts body weight
ii) foot inverters and everters - contract in a balanced manner to stabilise the foot
iii) gluteus minimum, medius and tensor fascia lata - abduct the lower limb (keeping pelvis level by counteracting imbalance created from having most of body-weight on 1 leg)
Which muscles are involved in the toe off stage (pre-swing)?
i) hamstring muscles - extend leg at hip
ii) quadriceps femoris - maintains extended position of knee
iii) posterior compartment of leg (gastrocnemius, soleus and tibialis posterior) - plantarflexes ankle
Name the stages of the swing phase.
1. leg lift
- initial swing
- terminal swing
Which muscles are involved in the leg lift stage?
i) iliopsoas and rectus femoris - flex the lower limb at the hip, driving knee forwards
ii) hamstring muscles - flex lower limb at knee joint
iii) anterior compartment of leg - dorsiflex ankle
Which muscles are involved in the swing stage?
i) iliopsoas and rectus femoris - keep hip flexed, resisting gravity as it tries to pull leg down
ii) quadriceps femoris - extends the knee, positioning foot for landing
iii) anterior compartment of leg - maintains ankle dorsiflexion so heel is in place for landing
What produces forward motion during walking?
1- 'push off' of the toes during flexion of metatarsophalangeal joints
2- forward swing of the hips accentuated by swinging movements of pelvis
What prevents dropping of the pelvis when swinging leg is off the ground?
Name the 3 types of contraction that allow muscle work during the gait cycle.
1. concentric (shortening) - accelerate/power generation
2. eccentric (lengthening) - decelerate/power absorption
3. isometric (same length) - stability
What is the difference between kinematics and kinetics?
Kinematics describes motion: joint angles, displacements, velocities, accelerations
Kinetics describes the things that cause motion: forces and moments
How is energy conserved during walking?
1. minimise excursion of centre of gravity
2. control momentum
3. transfer energy between body segments (contraction or passive movements, i.e. ligament elasticity)
4. phasic muscle action (e.g. resting/working of tibialis anterior)
What is the difference between a stride and a step?
- Stride = distance from IC right to IC right
- Step = distance from IC right to IC left
So 2 steps for 1 stride if even gait.