Gait

Question 1

What is gait?

Answer 1

• 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

Question 2

What is the gait cycle?

Answer 2

period of time from initial contact of foot to next initial contact on the same side (i.e. full revolution of 1 limb)

Question 3

What are the 2 phases of the gait cycle?

Answer 3

• stance phase (60%) - foot contacts floor

- swing phase (40%) - foot has no contact with floor

Question 4

What is the difference between running and walking?

Answer 4

• 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.

Question 5

Name the stages of the stance phase.

Answer 5

1. initial contact (heel strike)
2. loading response

support stage:

3. mid-stance (foot flat)
4. terminal stance (heel off)
5. pre-swing (toe off)

Question 6

Which muscles are involved in the initial contact stage?

Answer 6

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

Question 7

Which muscles are involved in the mid-stance and terminal stance (support stage)?

Answer 7

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)

Question 8

Which muscles are involved in the toe off stage (pre-swing)?

Answer 8

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

Question 9

Name the stages of the swing phase.

Answer 9

1. leg lift
2. swing:
   - initial swing
   - mid-swing
   - terminal swing

Question 10

Which muscles are involved in the leg lift stage?

Answer 10

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

Question 11

Which muscles are involved in the swing stage?

Answer 11

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

Question 12

What produces forward motion during walking?

Answer 12

1- ‘push off’ of the toes during flexion of metatarsophalangeal joints
2- forward swing of the hips accentuated by swinging movements of pelvis

Question 13

What prevents dropping of the pelvis when swinging leg is off the ground?

Answer 13

hip abductors

Question 14

Name the 3 types of contraction that allow muscle work during the gait cycle.

Answer 14

1. concentric (shortening) - accelerate/power generation
2. eccentric (lengthening) - decelerate/power absorption
3. isometric (same length) - stability

Question 15

What is the difference between kinematics and kinetics?

Answer 15

Kinematics describes motion: joint angles, displacements, velocities, accelerations

Kinetics describes the things that cause motion: forces and moments

Question 16

How is energy conserved during walking?

Answer 16

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)

Question 17

What is the difference between a stride and a step?

Answer 17

• 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.

Question 18

What is gait cadence?

Answer 18

steps per minute