Gait

Question 1

What are the requirements for gait

Answer 1

Progression: ability to generate a basic locomotor pattern (bodily movement eg. Walking) that can move the body in the desired direction
Postural control: ability to control the body’s position in space to accomplish both orientation and all aspects of stability, including steady-state, reactive, and anticipatory balance control.
Adaptation: ability to adapt gait (progression and postural control) to meet the individual’s goals and the demands of the environment.

Question 2

What are the neural controls of gait

Answer 2

Cortex – adaptation to goals and environment
Cerebellum – coordination, timing size of response, tone = stability
Brainstem/Basal ganglia – movement initiation, muscle activation and speed control
Spinal cord – normal rhythmic patterns (central pattern generators). Modulate reflex action
Somatosensory – visual, vestibular, mechanoreceptors contribute to recovery of gait stability following contact with an obstacle

Question 3

Describe the action of the hip extensors during gait

Answer 3

Late phase of swing phase = act to decelerate hip flexion, start hip extension and prepare for weight acceptance
Heel contact to mid stance = support body weight and generate hip extension
Swing phase = Glut. Max is mostly inactive

Question 4

Describe the action of the hip flexors during gait

Answer 4

Terminal stance = 30-50% of gait, eccentric contraction to decelerate hip extension
Swing phase = active only during first half of swing, second half is due to the forwards momentum (inertia) of the lower limb

Question 5

Describe the action of the knee flexors during gait

Answer 5

Heel contact = knee flexors active just before and after heel contact
Before = decelerate the knee extension for placement of foot on the ground
After = contribute to hip extension

Question 6

Describe the action of the ankle and foot dorsiflexors during gait

Answer 6

Heel contact = eccentric contraction to decelerate plantarflexion, if not tib. Ant. Actions would have foot slap
Swing phase = dorsiflex (prevent toes from dragging on the ground)

Question 7

Describe the action of the ankle plantar flexors during gait

Answer 7

Stance phase
Active most of the time, from 10% of gait cycle to heel off = eccentric contraction
Heel off to toe off = concentric contraction for forwards propulsion

Question 8

What are the functional tasks of gait

Answer 8

1. Weight acceptance; transfer of body weight soon as it contacts the ground, acts for shock absorption and maintain/preserve forward momentum
2. Single limb support; support entire body weight, forward progression of body weight, maintain stability
3. Limb advancement; advancing the limb forward and prepares for initial contact

Question 9

What are the spatial parameters of the gait cycle

Answer 9

• Stride length – distance covered by 2 sequential points of initial contact on the same foot
• Step length – distance between a point on one foot and the same point on the contralateral foot
• Foot angle – angle between the line of progression from the mid heel and the line of progression between the mid heel and the base of the second metatarsal
  . Positive foot angle is when foot face outwards – negative when inwards
• Step width – distance between the line of progression between each foot

Question 10

What are the temporal parameters for the gait cycles

Answer 10

• Cadence – number of steps per unit time – normal 100-120 steps/min
• Velocity – Rate of linear forward movement of body – distance over time

Question 11

When are the peaks and low oscillations of the gait cycle

Answer 11

This peaks at mid-stance phase of each limb, but is the lowest when both feet are in contact with the ground