MSK6 L19 - Gait Cycle Flashcards
During what activity is there no period of double support?
running
what is float/aerial phase?
during running when both feet are not on the ground
what muscles primarily keep us upright when standing?
2
extensor muscles of the back and plantarflexors
what do the knees do when standing?
knees are ‘locked’ so all ligaments are taut
T or F?
the centre of gravity is anterior to the ankle joint when standing
True, people tend to fall forward but plantarflexors counteract the natural ‘fall’
from standing what to do the plantarflexors do when initiating the gait cycle?
relax
What are the 4 phases of gait?
- heel-strike
- support
- toe off
- swing
1-3 = stance, 4 = swing
What position are the ankle, knee and hip in during heel-strike (front foot)?
- ankle joint is dorsiflexed
- knee is extended
- hip is flexed
What muscles are acting on the hip, knee and ankle during heel-strike?
- ankle = tibialis anterior
- knee = quadriceps
- hip = iliopsoas, rectus femoris, sartorius
What function does the hip joint have during heel strike?
shock absorption
What function does the hip joint have during mid stance? What muscles are being used?
maintains limb and trunk stability
hip abductors = glute meds, mins, TFL
What function does the hip joint have during late stance?
accelerate the body
What function does the hip joint have during mid swing? What muscles cause this?
foot clearance off the ground, iliopsoas, rectus femoris
What function does the hip joint have during late swing?
decelerate the body
hip extensors contract to decelerate the forward movement
high heels put increased pressure on what joints during stance?
metatarso-phalangeal
what is metatarsalgia?
pain in the ball of the foot
what two actions are increased when walking in high heels and at what phase?
knee flexion and plantarflexion at heel strike
Why does walking in high heels make you fatigue faster?
increase muscle activities
where does the shock go when walking in high heels in heel strike?
metatarsals instead of calcaneus
what function does the ankle joint have at heel strike? what muscles cause it?
shock absorption, initial impact deceleration
dorsiflexors contract to lower foot to the ground
what function does the ankle joint have at mid stance? what muscles cause this?
movement forward
dorsiflexors contract to pull tibia forwards over the foot, then gravity and momentum cause you to move forward
what function does the ankle joint have at late stance? what muscles cause this?
accelerates the body forward
plantarflexors = triceps surae
for toe-off
what function does the ankle joint have at mid swing? what muscles cause this?
foot clearance off the ground
dorsiflexors = tibialis anterior
toe extensors = extensor hallicus longus, extensor digitorum longus
what function does the ankle joint have at late swing?
deceleration in preparation for stance phase
dorsiflexors and toes extensors ensure foot is in optimal position for heel strike
What happens to the muscles with age?
they get weaker/atrophy
What happens to the muscles with age?
they get weaker/atrophy
What changes occur to the posture with age?
flexed posture in lower limb during standing, flexed neck
Does balance get better or worse with age?
balance gets worse/becomes compromised as muscles get weaker
What happens to gait speed and time at each stage of gait with age?
gait is slower, stride length is decreased
increased stance time, more time in double stance, less propulsive forces developed
What is ADT?
Androgen Deprivation Therapy is a kind of hormone therapy often used to treat prostate cancer
What are side effects of ADT in men?
muscle atrophy and increased fat
What affects does leg muscle atrophy have?
4
- reduced muscle force
- step width increases
- forward acceleration decreases
- at risk of falling and bone fracture
What affects does muscle atrophy have?
4
- reduced muscle force
- step width increases
- forward acceleration decreases
- at risk of falling and bone fracture
What affects does muscle atrophy have?
4
- reduced muscle force
- step width increases
- forward acceleration decreases
- at risk of falling and bone fracture
What effects are casued by damage to the superior gluteal nerve?
unable to maintain pelvis level during single leg stance (contralateral drop)
What effects are casued by damage to the superior gluteal nerve?
unable to maintain pelvis level during single leg stance (contralateral drop)
What effects are casued by damage to the superior gluteal nerve?
unable to maintain pelvis level during single leg stance (contralateral drop)
how does the body compensate for a contralateral drop?
the hip drops so trunk flexes to the opposite side to balance centre of mass when walking so lateral trunk flexion is the compensation movement
What effects are caused by damaged anterior leg muscles?
weak dorsiflexion, toes don’t clear during swing, foot slap/foot drop after heel-strike
What effects are caused by damaged anterior leg muscles?
weak dorsiflexion, toes don’t clear during swing, foot slap/foot drop after heel-strike
how does the body compensate for foot slap/foot drop?
knee raised high during swing in order to clear the ground and bring the foot up
