Gait

Question 1

total vertical displacement during gait

Answer 1

5cm

Question 2

total side-to-side displacement during gait

Answer 2

4cm

Question 3

what COM minimization strategies decrease downward COM displacement

Answer 3

transverse pelvic rotation and sagittal ankle rotation

Question 4

what COM minimization strategies decrease upward COM displacement

Answer 4

stance knee flexion and frontal pelvic rotation

Question 5

what does frontal hip rotation do in regard to COM minimization strategy?

Answer 5

decrease side-to-side COM motion

Question 6

Erector Spinae during gait

Answer 6

Prevents trunk from falling forward over hips at heel contact

Question 7

Rectus abdomnis during gait

Answer 7

Stabilizes hip flexor activity

Question 8

Hip extensors during gait

Answer 8

Similar role to ES @ heel contact; additional activity for propulsion

Question 9

Hip flexors during gait

Answer 9

Tough to measure, but probably active eccentrically well before toe off through first half of swing phase

Question 10

hip abductors during gait

Answer 10

Prevent contralateral pelvic drop in single support (eccentric)

Contralateral COM propulsion in late stance (concentric)

Also, rotate contralateral (i.e. swinging) side fwd in stance phase

Question 11

hip adductors during gait

Answer 11

Heel contact burst -> stabilizer role, extensor role
Toe off burst -> initiate hip flexion

Question 12

Internal rotators during gait

Answer 12

rotate contralateral (i.e. swinging) side fwd in stance phase

Question 13

hip external rotators during gait

Answer 13

Control hip internal rotation in stance (eccentric)

Question 14

knee extensors during gait

Answer 14

Eccentric control during weight acceptance

Question 15

knee flexors during gait

Answer 15

Activity appears mostly directed at early stance phase hip extension and stabilization of knee extension

Question 16

Tibialis anterior during gait

Answer 16

Decelerates PF (and pronation) from heel contact to foot flat

Activates concentrically to ensure toe clearance in swing

Question 17

extensor digitorum longus/extensor hallucis longus during gait

Answer 17

Decelerates PF from heel contact to foot flat

Activates concentrically to ensure toe clearance in swing

Like tin ant, but without the pronation

Question 18

ankle plantarflexors during gait

Answer 18

Foot flat to heel off -> eccentric control of DF
Heel off to toe off -> fwd COM propulsion (concentric)

Question 19

tibialis posterior during gait

Answer 19

Decelerates pronation from heel contact to mid stance

Concentrically supinates foot from mid stance to toe off

Question 20

Fibularis group during gait

Answer 20

Stabilizes activity of tib post
Holds first ray on the ground

Question 21

intrinsics of foot during gait

Answer 21

Mid stance to toe off -> raise the medial longitudinal arch