Learn: Gait analysis: Total limb and bilateral limb synergies, PHAT, Quiz 5 questions

10° anterior tilt, 5° forward rotation, neutral frontal plane

What is the position of the pelvis at initial contact?

20 degrees of flexion

What is the position of the hip at initial contact?

20 degrees flexion

What is the position of the hip/thigh at initial contact?

5° flexion (appears extended)

What is the position of the knee at initial contact?

Neutral

What is the position of the ankle at initial contact?

Neutral

What is the position of the subtalar joint at initial contact?

Initiation of heel rocker, impact decelerated, heel first contact

What are the critical events of initial contact?

Decreases stability of Ankle and Hip but increases the stability of knee

How do ground reaction forces affect the stability of each joint?

Ankle: Isometric Tibialis anterior (Impact resistance)

Hip: Hamstrings and Glute max (to start hip extension)

Knee: Vastii, IT band (connected to upper glute max), Hamstrings (protective)

What muscles are activating at total contact?

1 cm

____ cm fall before the heel reaches the floor

10° anterior tilt, 5° forward rotation, 5° contralateral drop

What is the position of the pelvis during loading response?

20° flexion

What is the position of the thigh/hip during loading response?

20° flexion

What is the position of the knee during loading response?

5° plantarflexion then neutral

What is the position of the ankle during loading response?

5° eversion

What is the position of the subtalar joint during loading response?

Heel rocker progression, Restrained ankle plantarflexion, restrained knee flexion, sustained hip flexion

What are the critical events of loading response?

Ankle: Tibialis anterior (resisting PF and subtalar eversion)

Knee: Vastii and Hamstrings (Co contraction controls stance phase knee flexion while hams facilitate active hip extension. Co contraction also reduces liklihood of ACL strain/tear)

Hip: Hamstrings and Glute Max (starts extension) Abductor muscles (Glute med, Upper glute max, posterior TFL, to slow hip drop)

What muscles are activating during loading response?

10° anterior tilt, neutral (0°) rotation, neutral (0°) frontal plane

What is the position of the pelvis at midstance?

extension to neutral (0°)

What is the position of the hip/thigh at midstance?

5° flexion (appears extended)

What is the position of the knee at midstance?

5° plantarflexion into 5° dorsiflexion

What is the position of the ankle at midstance?

decreasing eversion

What is the position of the subtalar joint at midstance?

Ankle: Triceps Surae, Tib posterior/Soleus (restrains dorsiflexion during ankle rocker)

Knee:

Hip: hamstrings (Because knee is extending, hamstrings augment hip extension)

Knee: Quadriceps

What muscles are activating during midstance?

Restrain ankle dorsiflexion, Knee extension, Frontal plane hip stabilization

What are the critical events of midstance?

The knee to the ankle

As the limb rolls forward, the critical site for dynamic limb stability shifts from __________________ to __________________

Midstance

Intense hip and knee action from loading response terminates by _________________

10° anterior tilt, 5° backward rotation, neutral frontal plane

What is the position of the pelvis at terminal stance?

20° apparent hyperextension

What is the position of the thigh/hip at terminal stance?

5° flexion (appears extended)

What is the position of the knee at terminal stance?

10° dorsiflexion with heel-off

What is the position of the ankle at terminal stance?

Eversion decreases to 2° by end of phase

What is the position of the subtalar joint at terminal stance?

Controlled ankle dorsiflexion with heel rise, trailing limb posture, free forward fall of body weight

What are the critical events of terminal stance?

Hip: Anterior TFL (Restrains rate and extent of passive hip extension, provides continued abduction force)

Knee: Popliteus and Gastrocnemius (Resists anterior ground reaction force)

Ankle: 7 plantarflexors peak in power (control ankle dorsiflexion)

What muscles are activating at terminal stance?

Soleus, Gastrocnemius, Flexor digitorum longus, Flexor hallucis longus, Posterior tibialis, Peroneus longus, Peroneus brevis

What are the 7 PF muscles that peak in terminal stance?

10° anterior tilt, 5° backward rotation, 5° ipsilateral drop

What is the position of pelvis during preswing?

moves from 10° apparent hyperextension to neutral

What is the thigh/hip doing at preswing?

40° flexion

What is the knee doing at preswing?

15° plantar flexion

What is the ankle doing at preswing?

Neutral

What is the subtalar joint doing at preswing?

Toe rocker, knee flexion to 40

What are the critical events of preswing?

Hip and Knee: Rectus femoris, Gracilis, Sartorius (Flex hip and knee) Rectus femoris (assists with hip flexion, controls knee flexion)

Hip muscles: Illiopsoas

Knee: Gastrocnemius, Biceps femoris short head

Ankle: Elastic recoil of achilles tendon

Muscle activation during preswing

10° anterior tilt, 5° backward rotation, neutral frontal plane

What is the position of the pelvis at initial swing?

15° flexion

What is the position of the thigh at initial swing?

60° flexion

What is the position of the knee at initial swing?

from 15 to 5° plantar flexion

What is the position of the ankle initial swing?

Neutral

What is the position of the subtalar joint during swing phase?

Knee flexion, hip flexion

What are the critical events of initial swing?

Ankle: Tib anterior, toe extensors (Toe clearance)

Knee: Biceps femoris short head, Gracilis, sartorius

Hip: Passive limb advancement (due to ankle's propulsive mechanics)

What muscles are activating during initial swing?

10° anterior tilt, neutral (0°) transverse and frontal plane rotation

What position is the pelvis in during midswing?

25 degrees flexion

What position is the thigh/hip in during midswing?

25 degrees flexion

What position is the knee in during mid swing?

Neutral

What position is the ankle in during mid swing?

Ankle dorsiflexion to neutral, hip flexion

What are the critical events of midswing?

Hip: virtually passive hip flexion

Knee: Passive knee extension

Ankle: plantarflexors

Muscle activation during midswing

10° anterior tilt, 5° forward rotation, neutral (0°) frontal plane

What is the pelvic position during terminal swing?

20 degrees flexion (subtle past retract)

What is the hip/thigh doing during terminal swing?

5 degrees flexion

What is the knee position during terminal swing?

Neutral

What is the ankle position during terminal swing?

Ankle: Pretibials (prepare for initial contact)

Knee: Semitendonosis, Semimembranosis, Biceps femoris long head (Deceleration, prep for IC)

Hip: Hamstrings, glute max (Deceleration)

Muscle activations during terminal swing

Hip deceleration, Inhibition of further hip flexion, Knee deceleration, Knee extension, ankle dorsiflexion

What are the critical events at terminal swing?

1. weight transfer

2. Transition

3. Progression

What are the three reciprocal synergies of walking

IC/Loading response, Preswing

What two events are happening during weight transfer?

One leg accepts weight while the other pushes off

What is going on during weight transfer?

One leg supports you while the other clears the ground

What is going on during transition?

Stance leg rolls over forefoot while the other prepares to land

What is happening during progression?

Equal, double sinusoidal path

Vertical displacement of the sacrum, trunk in head is _________________ for each segment, and follows a ______________________ path.

4.2 cm

How much vertical displacement of Sacrum trunk and head?

Loading response, preswing

When does peak downward deviation occur? (Hint, double limb support)

Midstance & terminal stance, midswing

When does peak ascent of PHAT occur?

Increases

How does vertical trunk excursion respond to faster gait?

4.5 cm

What is the average lateral displacement during gait?

Single sinusoid

What is the path for lateral displacement?

Onset of terminal stance

When does maximal lateral displacement over the stance limb occur?

Initial contact to midstance (First third of the GC)

PHAT Is faster than mean walking speed at

Terminal Stance to Terminal swing (45-95%)

PHAT is slower than walking speed at

23 cm/sec

The sacrum is ____ faster than mean walking speed for the first third of the gait cycle

14 cm/sec

Thorax is _____ faster than mean walking speed at first third of the GC

3 cm/sec

The head is ____ faster than the mean walking speed during the first third of the GC

15 cm/sec

At 45% and 95% of cycle (TSt & TSw) Sacrum is _________ slower than mean walking speed

8 cm/sec

At 45% and 95% of cycle (TSt & TSw) Thorax is _______ slower than mean walking speed

2 cm/sec

At 45% and 95% of cycle (TSt & TSw), the head is __________ slower than mean walking speed

attenuation of accelerations at the head

What provides a stable visual frame of reference?

Activation of the paraspinal muscles

how does the attenuation of accelerations at the head occur?

4° Anterior Tilt, 4° Pelvic Obliquity, 10° Rotation

What are the motions of the pelvis during gait?

Hip abductors and Extensors

What muscles control the pelvis?

Late terminal swing to middle of midstance

When do hip extensors activate to control the pelvis?

Minimal muscle action

How is stabilization of the trunk accomplished during quiet standing?

Contralateral IC

When is the prime activity of erector spinae during gait?

Multifidus, Rotatores, Quuadratus lumborum

Which spinal muscles have greater ipsilateral effort than contralateral effort?

Erector spinae, Multifidus, Rotatores, Quadratus lumborum, External obliques, Rectus abdominus

What are the muscles working to stabilize trunk during gait?

IC, Bilaterally

When does Multifidus activate and where?

about 1/2 a stride

How far away is the trunk from the lead foot during initial contact?

Near midline but moving towards the side of the contact foot.

What is the trunk doing during initial contact in the frontal plane?

5

In the transverse plane, the pelvis is rotated forward about ___ degrees at IC

Left shoulder and arm anterior, Right pelvis anterior

What does posture look like at initial contact?

Mid stance

When does vertical and anterior displacement of the trunk return to neutral?

20mm

How much above the mean is the trunk apex at loading response?

50%

How much is timing of the two arms offset?

Ipsilateral heel contact

When does peak extension of each arm occur?

Contralateral Initial contact

When does peak flexion of each arm occur?