lecture 24: anatomy of gait part 1 Flashcards
humans are bipedal with two major gaits, what are they
walking and running
what are the 2 phases of the walking gait cycle
stance phase
swing phase
which phase is longer in the walking cycle
stance phase
what is one walking cycle defined as
from heel strike to heel strike of same limb (1x stance, 1x swing)
what marks the begining of the total gait cycle
intial contact
what is the first aspect of the walking cycle
initial contact
what is the second event in the walking cycle
loading response
explain loading response
full plantar surface of the foot makes contact with the ground
what is the third event in the walking cycle
mid stance
what is mid stance
the body’s center of gravity is directly over the moving foot, before transferring to the supporting foot
what is the 4th even in the walking cycle
terminal stance
what is the 5th event in the walking cycle
preswing and begining of toe off
what event marks the end of stance pahse
toe off (pre swing)
initial contact also knwon as
heel strike
end of the stance phase is also known as
toe off
true or false: in the walking gait cycle, there are single (one foot on ground only) support phases only
false also double support (both feet) phases
what are the double support phases/events in the stance phsse
initial contact
loading response
preswing
what are the sing support phases/events in the stance phsse
mid stance
terminal stance
what are the 5 events of the stance phase in ordeer
initial contact/heel strike
loading response
midstance
terminal stance
preswing
what are the 3 events in the swing phase of gait
intial swing
mid swing
terminal swing
true or false, all the events in the swing face are single support
true
toe off markrs the begining of what event
initial swing
be able to understance gait cycle in motion (https://www.youtube.com/watch?v=b1o2-nXo3Js)
during the gait cycle, lower limb muscles must do what three things
propel the body forward by generating angular motions of the limb segments
support body weight (ie. resist external forces that produce unwanted torques at some of the lower limb joints)
all while miniminzing energy expenditure
the lower limbs propel the body forward by doing what
generating angular motions of the limb segments
true or false: ground reaction force is approximately equivalent to body weight and explai
true,
when your body hits the ground, the ground imposes and equal and opposite force/reaction to u
lower limb joint mocement involves what type of motion
angular
the largest joint motions in the lower limb occur in what place
saggital place
the largest joint motions in the lower limb occur in the sagittal plane involved what ROM at the hip ,knee, ankle
involving flexion/extension of the hip. knee, ankle (and MTP/IP joints)
true or false: the only joint motions occur only in the saggital plane and explain
false, hips move in other planes involving abduction/adduction (coronal) and medial/lateral rotation (transverse)
hips move in other planes involving besides the saggital one, what are the other motions and the planes
abduction/adduction (coronal) and
medial/lateral rotation (transverse)
what are the ankle dorsiflexors
tib ant
extensor hallucis
digitorem longus
what is the function of the ankle dorsiflexors in the stance phase form initial contact to end of loading response
prepare foot for heel strike (clear toes from gound)
control plantar flexion through looading response
explain how the ankle dorsiflexors in the stance phase form initial contact to end of loading response control plantar flexion through loading response
in the intiial contact/heel strike
the GRF is posterior to the ankle joint causing a plantar flexor torque (foot slap) therefore you must recreuit the dorsiflexors to keep the toes off the ground and prevent foot slap
what is the function of the hip extensors in the stance phase form initial contact to end of loading response
control hip flexion through foot flat (loading response)
extend hip into midstance
the hip extensors in the stance phase form initial contact to end of loading response control hip flexion through foot flat
GRF passing anterior to the hip flexors therefore causing a flexion toque therfore hip extensors (glutes) need to be recruited to prvent excess hip flexion and keep hip extended
the hip extensors help extend the hip into midstance:
does that cause acceleration or deccleration
deccel
what is the function of the knee extensors in the stance phase form initial contact to end of loading response
extend knee to prepare for heel strike
control knee flexion through midstance
during the the stance phase form initial contact to end of loading response, what are the knee extensors at work
mostly the vastus group
explain how the knee extensors in the stance phase form initial contact to end of loading response control knee flexion through midstance
The GRF is passing posterior to the knee joint causing a flexion torque therefore the knee extensors must be recruits to prevent buckling of the knee
what muscles are activated at the very end of the loading response (foot flat)
plantar flexors (gastroc and soleus =triceps sura)
triceps surae is in reference to what muscles
gastroc and soleur
what is the function of the plantar flexors at the end of the loading response
control dorsiflexion
explain how/why the plantarflexors control dorsiflexion at the end of the loading response
during foot flat, the GRF is anterior to ankle joint causeing a dorsiflexion torque
the plantar flexors need to be activated to control for that
what is the function of the plantar flexors in the stance phase from midstance through toe off
control dorsi flextion until heel off
produce heel off and propel froward
(produce toe off torque)
what are the plantarflexors in the stance phase from midstance through toe off
triceps surae, tibialis post, digital flexiors, fib long and brev
what is the function of the instrinsic foot muscles (mostly plantar) in the stance phase from midstance through toe off
stiffen arches
make foot more rigit lever in prep for heel off
just before the swing phase, what muscles are recruit and why
hip flexors (initiating hip flex to clear the ground(
ankle dorsi flxors to clear the ground
what is the function of the hip flexors (rectus fem, illipsoas) in the stance phase just before swing phase
initiate hip flexior to clear ground
what is the function of the dorsiflexors in the stance phase just before swing phase
initiate dorsiflexion to clear ground
what is the function of the hip flexors in the swing phase
swing limb forward
true or false: in the swing phase when propelling limb, there is not GRF
true
what is the function of the knee flexors (hamstrings) in the swing phase
flexor knee to clear leg from ground
(as hip extensors- prepare for heel strike)
which muscles are acting as the main knee flexors in the swing phase
hamstrings
what is the function of the ankle dorsiflexors during the swing phase
dorsiflex to keep foot clear of ground
what is the function of the hip adductors during the swing phase
keep swing leg close to stance leg
assist in hip flexion (bringing swing leg forward)
during single support phase of the stance phase (loading response, mistance, terminal stance) body mass causes a tendency for the hips to do what
to drop/tilt towards contralateral side, recruiting hip abductors on stance leg counters this and keeps center of mass level
during single support phase of the stance phase (loading response, mistance, terminal stance) body mass causes a tendency for the hips to to drop/tilt towards what side
contralateral side
during single support phase of the stance phase (loading response, mistance, terminal stance) body mass causes a tendency for the hips to to drop/tilt towards contralateral side, how do we counteract this
recruiting hip abductors on stance leg counters this and keeps center of mass level
what is the function of the hip abductors (glute med/min, TFL) during the stance phase single support
stabilize/oppose hip adduction (pelvic tilt) during single support phase
during stance phase, the stance legs hip joint rotates which way
medially (inernally)
during stance phase, the stance legs hip joint rotates medially (interally) assisted by what
by minimus and medius which are already in use to abduct the hip
during the swing phase, the hip roates which way
laterally (externally)
during swing phase, the stance legs hip joint rotates laterally by recruit what muscles
lateral hip rotators (S/I gemelli, I/E obturatots, quadratus femoris, pifirmois)
during the stance phase, does the stance legs hip joint rotate medially or laterally
medially
during the swing phase, does the stance legs hip joint rotate medially or laterally
laterally
what is the main fucction of the muscles of the foot in walking
stiffen foot and arches
the foot muscles are active mostly during what part of gait
2nd phase of stance
what is the main function of the leg and ankle muscles durign walking
control dorsiflexion through midstance, generate plantarflexion in push off
what is the main functiin of the cheif dorsiflexors of the ankle during walking (tib ant, extensor hallucis longus, etensor digi longus)
control plantar flexion in loading response
generate dorsiflexion during swingphase to clear substate
(foot drop if dorsi does not get actviated)
if dorsiflexors do not get activated during swing phase to clear the ground and foot flat happens, what needs to be recruiteing instead
need more hip and knee flexion to clear the ground
what is the main function of the 3 vastus muscles during walking
control knee flexion to midstance and extend knee for heel strike
what is the main function of the rectus femoris durign walking
flex hip to clear substate and propel limb forward
what is the main functuon of the hamstrings when walking
flex knee (clear substante and move limb forward)
prepare for heel strike (hip extensors)
what is the main function of the gluteal region during walking
control hip flexion (max), control pelvis tilt (med, min tfl) and decelerate the limb
walking is what type of gait
compass Inverted pendulum)
running is what type of gait
mass spring
true or false: running has an aerial phase and double support
false, no double support
what is different about the phases between running and walking
running has an aerial phase
running has no double support
explain the differences in ground reaction forces for walkig vs running
GRF are 2-3x greater in running and walking and borne by a single limb
in running, the basic angular motions are similar but all the angular changes are greater so what does that mean
the muscles work harder to counter eternal forces (GRF) and proper COM (center of mass)
