Exam 3 Balance/Posture Part 3 Flashcards Preview

Biomechanics > Exam 3 Balance/Posture Part 3 > Flashcards

Flashcards in Exam 3 Balance/Posture Part 3 Deck (33):
1

T/F: At initial contact with the ground, the ankle is plantar flexed.

False; dorsiflexed

2

Plantar flexion occurs at what ankle joint during the loading response interval? Pronation?

plantar flexion at talocrural;
pronation at subtalar

3

T/F: At the end of the mid stance interval, the talocrural joint is maximally dorsiflexed and the subtalar joint begins to supinate.

True

4

T/F: From the mid stance to the terminal stance interval the foot is in pronation.

False; in supination

5

Which joint is aka talocalcaneal joint?

subtalar

6

T/F: Plantarflexion, adduction, and inversion make up the motion of pronating the foot.

False; these make up supination

7

T/F: Dorsiflexion, abduction and eversion make up the motion of pronating the foot.

True

8

During Midstance, what maintains the medial arch?

Plantar fascia

9

T/F: The plantar fascia is relaxed during the Windlass Effect.

False; fascia is pulled tight

10

What two events are crucial in creating the "rigid lever needed for ambulation"?

Windlass Effect and Close Pack Position

11

T/F: During the Windlass Effect, the toes are concentrically dorsiflexed.

False; toes are ECCENTRICALLY dorsiflexed

12

T/F: During Swing Phase the semispinalis, rotatores, multifidus, and external oblique muscles are active on the contralateral side.

False; active on ipsilateral side

13

T/F: during the swing phase, the psoas major and the quadratus lumborum help to support the pelvis on the ipsilateral side.

True

14

T/F: During the Swing phase, the erector spinae and internal oblique are active on the ipsilateral side.

False; contralateral side

15

T/F: During swing phase, the contralateral hip abductors provide support of the pelvis.

True

16

During which part of the swing phase will the rectus femoris, sartorius, gracilis, adductor longus, TFL, pectineus, and the short head of the biceps femoris all be active?

during initial swing

17

What is the prime mover of the LE from the early to mid portion of the swing phase?

iliopsoas

18

What muscles are strongly active during the terminal swing of the swing phase?

hamstrings and gluteus maximus (help decelerate hip flexion and knee extension)

19

During the initial stance of the stance phase, what muscle supports hip extension and also rotates the pelvis externally?

adductor magnus

20

T/F: During the mid stance of the stance phase, abductors help to stabilize the pelvis (eccentric)?

True

21

T/F: During the terminal stance of the stance phase, the gluteus medius and minimus remain active for lateral pelvic stabilization.

True

22

At what point of the swing phase do the quadriceps achieve peak activity?

during the loading response
(knee extensors contract slightly at the end of the swing period prior to heel strike)

23

The co-activation of what muscles during the loading phase of the swing phase will aid in maintaining joint stability, by equalizing the articular surface pressure distribution, and controlling tibial translation?

Hamstrings

24

During the swing phase, what 4 muscles contract concentrically to dorsiflex and invert the foot in preparation for the initial contact?

Tibialis anterior,
extensor digitorum longus (EDL),
extensor hallucis longus (EHL),
and fibularis tertius

25

Does the tibialis anterior work eccentrically or concentrically when lower the foot to the ground during the loading response interval of the swing phase?

eccentrically
(E for Ease it down; C for Come quick!)

26

During the swing phase, what muscle eccentrically contracts to evert the calcaneus?

tibialis posterior

27

During the swing phase, anterior movement of the tibia and talus is controlled by the eccentric action of what muscles?

gastocnemius and soleus

28

What muscles make up the triceps surae?

gastrocnemius and soleus

29

T/F: Triceps surae contract concentrically from mid stance to the late stance period to control ankle dorsiflexion as the COG moves forward.

False; eccentrically

30

T/F: At heel lift the action of the plantar flexors changes from eccentric to concentric.

True

31

What are the most important factors in absorbing the shock of impact during gait?

pronation of the subtalar joint and eccentric muscle actions

32

What motions are slowed as the tibialis anterior eccentrically contracts?

plantar flexion after heel strike and pronation after heel strike

33

What motions result from concentric action of the tibialis anterior?

dorsiflexion and inversion of the foot