Muscle Activation during Gait Flashcards
what produces an external torque during gait?
GRF
will cause movement at each joint of the LE
what produces an internal torque during gait?
primarily muscle activation
it is produced to match/overcome the external torque
when and why do concentric muscle contractions occur during gait?
they occur when the internal torque is moving the joint in the direction of the muscle’s activity
these provide stability and produce movement of a segment
when and why do eccentric muscle contractions occur during gait?
they occur when an internal torque is moving the joint in the direction opposite of the muscle’s action
these help with shock absorption and deceleration of a limb segment
what can cause muscular dysfunction and how will it impact gait?
Causes:
- weakness
- loss of power
- decreased endurance
- spasticity
- contracture
leads to altered gait patterns and compensations as the torque GRFV doesn’t change but the individual’s ability to counter it does
what muscles are activated at the hip in the sagittal plane during IC?
ALL hip extensors contract concentrically to prepare for LR
what muscles are activated at the knee in the sagittal plane during IC?
eccentric hamstring contraction to counteract extension torque
knee extensions transition from concentric to eccentric contraction in preparation for LR
what muscles are activated at the ankle in the sagittal plane during IC?
pretibials (tibialis anterior, big toe extensors) contract concentrically
what muscles are activated at the hip in the sagittal plane during LR?
concentric contraction of hip extensors
(Glute max, adductor magnus, TFL, Glute med peak)
what muscles are activated at the knee in the sagittal plane during LR?
eccentric contraction of knee extensors
(quad activity peaks)
what muscles are activated at the ankle in the sagittal plane during LR?
eccentric contraction of ankle DF (tibialis anterior peaks)
Transition to eccentric contraction of ankle PF in late LR
what muscles are activated at the hip in the sagittal plane during MSt?
no hip muscular activity requried in the sagittal plane
what muscles are activated at the knee in the sagittal plane during MSt?
quads eccentric to no activity
what muscles are activated at the ankle in the sagittal plane during MSt?
eccentric contraction of the gastroc/soleus
what muscles are activated at the hip in the sagittal plane during TSt?
minimal activity in the sagittal plane
what muscles are activated at the knee in the sagittal plane during TSt?
no quad or HS activity
tibial position maintained by gastroc
what muscles are activated at the ankle in the sagittal plane during TSt?
concentric contraction of ankle PF to prevent tibial collapse with heel rise
Gastroc/Soleus activity peaks
what muscles are activated at the hip in the sagittal plane during PSw?
concentric contraction of hip flexors
adductor longus peaks
what muscles are activated at the knee in the sagittal plane during PSw?
knee flexion is mainly passive
slight concentric contraction of knee flexors and eccentric rectus
what muscles are activated at the ankle in the sagittal plane during PSw?
ankle PF activity ceases in early PSw and passive tension contributes to ankle moving in PF
ankle DF concentric initiated at the end of PSw
what muscles are activated at the hip in the sagittal plane during ISw?
continued concentric contraction of hip flexors
Iliacus peaks
what muscles are activated at the knee in the sagittal plane during ISw?
concentric contraction of knee flexors
(biceps femoris SH, sartorius, gracilis peak)
flexion continues to be aided by flexion at the hip
what muscles are activated at the ankle in the sagittal plane during ISw?
concentric contraction of tibialis anterior
toe extensor activity peaks
what muscles are activated at the hip in the sagittal plane during MSw?
continued concentric contraction of hip flexors
initation of eccentric hip extensors (HS) to control hip flexors
what muscles are activated at the knee in the sagittal plane during MSw?
knee extension created by momentum
knee flexors contract eccentrically at the end of MSw to control extension
what muscles are activated at the ankle in the sagittal plane during MSw?
continued concentric contraction of DF
what muscles are activated at the hip in the sagittal plane during TSw?
concentric contraction of hip extensors
what muscles are activated at the knee in the sagittal plane during TSw?
concentric contraction of knee extensors to insure full extension
peak hamstring eccentric contraction to decelerate thigh
what muscles are activated at the ankle in the sagittal plane during TSw?
continued concentric contraction of DF
Describe the relative joint position and muscle activity at the hip in the sagittal plane during gait
use the chart
describe the relative joint position and muscle activity at the knee in the sagittal plane during gait
use the chart
describe the relative joint position and muscle activity at the ankle in the sagittal plane during gait
use the chart
what muscles are activated at the hip in the frontal plane during LR and MSt?
- LR → hip abductors contracting eccentrically
- Glute med and adductor magnus at peak
- MSt → hip abductors contracting eccentrically then concentrically
what muscles are activated at the ankle in the frontal plane during LR and MSt?
invertors contracting eccentrically during both phases
what muscles are activated at the hip in the frontal plane during TSt and PSw?
hip abductors contracting concentrically
what muscles are activated at the ankle in the frontal plane during TSt and PSw?
invertors contracting concentrically
what muscles are activated at the hip in the frontal plane during the entire swing phase?
hip adductors contract concentrically
what muscles are activated at the ankle in the frontal plane during the entire swing phase?
evertors contract concentrically
describe the relative joint position and muscle activity at the hip in the frontal plane during all of gait
use the diagram
describe the relative joint position and muscle activity at the ankle in the frontal plane during all of gait?
use the diagram below
what are the key roles of the ankle dorsiflexors during gait?
eccentric activation to control plantarflexion of the ankle at IC until foot flat
what are the key roles of the ankle plantarflexors during gait?
- eccentric contraction moving into MSt to control tibial advancement
- concentric contractions at TSt assists with forward propulsion
what are the key roles of the ankle invertors during gait?
- eccentrically contracts to control pronation until MSt
- concentrically contracts to supinate the foot for push off in TSt/PSw
what are the key roles of the ankle evertors during gait?
also active as co-contraction to counter strong inversion effect occuring during LR/MSt
what are the key roles of the knee extensors during gait?
- eccentrically control knee flexion in LR
- Concentrically to extend the knee and support the body in MSt
what are the key roles of the knee flexors during gait?
Decelerate knee extensors in preparation for placement of the foot on the ground
what are the key roles for the hip extensors during gait?
activated in TSw prior to IC to initiate hip extension and prepare LE for weight acceptance at the beginning of stance
what are the key roles for the hip flexors during gait?
advance LE forward during ISw
Concentrically lift LE to allow for toe clearance during swing
what are the roles of the hip abductors during gait?
Control the slight lowering of the contralateral pelvis on the side of the swing limb then provide pelvic stability in stance
what are the key roles of the hip adductors during gait?
assist with the initation of hip flexion after toe off
List some gait deviations
- Trendelenburg gait
- compensated trendelenburg gait
- foot slap
- knee extension thrust
what phase of gait is Trendelenburg gait observed?
LR → PSw
(observed best in frontal plane)
what does Trendelenburg gait look like?
excessive downward drop of the contralateral pelvis during stance
what is the cause of both Trendelenburg and compensated Trendelenburg gait?
glute medius weakness
what is the result of Trendelenburg gait?
a functionally longer swing limb resulting in decreased efficiency and possibly decreased stance time
what differentiates Trendelenburg from compensated Trendelenburg gait?
compensated Trendelenburg gait utilizes a trunk lean over the stance leg to try and maintain a level pelvis
what does a foot slap gait look like? what phase of gait is it most noticed and in what plane?
PF torque goes unchecked by anterior tib
occurs during IC → LR
best observed in the sagittal plane
what are some potential causes of a foot slap gait?
tib anterior weakness
(from a peroneal nerve palsy or peripheral neuropathy)
what is the result/impact of “foot slap” on gait?
rapid PF after heel contact which can be audible
usually can clear foot during swing
what does a knee extension thrust during gait look like? what phases does it typically occur in and what plane is the best to view it?
knee snapping back into extension early in stance phase
phase → IC
plane → sagittal
what are some potential causes of a knee extension thrust gait deviation?
quad spasiticy from UMN lesion
what is the result/impact of a knee extension thrust gait deviation?
rapid and often excessive knee extension during LR, can occur w/cause knee hyperextension over time
