Lecture 16: Gait Flashcards
Describe walking gait cycle
Cyclic
Locomotion
Name phases of walking gait cycle
Stance phase - 60% of cycle
Swing phase -40% of cycle
Name components of stance phase
Double support (both feet on ground)= initial contact - Heel strike, loading response
Single support (one foot on grounf) = mild stance, terminal stance
Double support = pre swing (toe off)
Name components of swing phase
All single support= initial swing (toe off), mid swing, terminal swing (heel strike)
What is one walking gait cycle
From heel strike to heel strike - of the same limb
1x stance phase, 1x swing phase
Describe grounf reaction force
Shifts direction and magnitude
Roughly equal to body wight
Opposite of your force
Will created unwanted forces on body- muscles oppose it
Name the 3 msucle functions during gait
Propel body forwards
Supports body weight
Minimizing energy expenditure - evolutionary purpose
Describe how lower limb muscles propel
Generate angular motions of limb segments
Rotation of joints = translate to linear motion
Describe how lower limb muscles support body weight
Resist external forces, these produce unwanted torques at some of the lower limb joints
Name stages of stance phase - flexion/ extension
Initial contact - heel strike to end of loading response
Midstance through toe off
Name parts of heel strike to end of loading response
Heel strike - initial contact - double support
Loading response - foot flat - single support
Heel strike (initial contact) and loading response (foot flat) = what is active
Ankle dorsiflexors
Hip extensors
Knee extensors
At very end of loading response = plantarflexors
Heel strike (initial contact) and loading response (foot flat) = ankle dorsiflexors
Tibialis anterior, extensor hallucis and digitorum longus
—> prepare for heel strike
—> Control plantarflexion through loading response - so can Load foot in controlled manner
Heel strike (initial contact) and loading response (foot flat) = hip extensors
Gluteus Maximus, hamstrings
—> Control hip flexion through foot flat (grf ant to hip joint, glute max contracts eccentrically)
—> Extend hip into midstance (until foot flat cause then gfr passes directly though hip joins)
Heel strike (initial contact) and loading response (foot flat) = Knee extensors
Mostly vastus group
—> Extend need to prepare for heel strike (at end swing phase = prepare for heel strike)
—> Control knee flexion through midstance
(Flexor torque during foot flat phase)
Heel strike (initial contact) and loading response (foot flat) = Plantarflexors
At very end of loading response
Gastrocnemius + soleus = triceps surae
—> Control dorsiflexion
Name parts of midstance through toe off
Single support = midstance (grf moves along foot clockwise)
Terminal stance heel off (start push off)
Pre swing - toe off (end push off)
Midstance, terminal stance (heel off) and preswing (toe off) = what is active
Plantarflexors
Intrinsic foot muscles
Just before swing phase = hip flexors, ankle dorsiflexors
Midstance, terminal stance (heel off) and preswing (toe off) = plantarflexors
Triceps surae, Tibialis posterior, digital flexors, fibularis longus/brevis
—> Control dorsiflexion until heel off (then push concentrically)
—> Produce heel off and propel forward
Midstance, terminal stance (heel off) and preswing (toe off) = Intrinsic foot msucles
Mostly plantar
—> Stiffen arches
Make foot right lever in preparation for heel off
Midstance, terminal stance (heel off) and preswing (toe off) = Hip flexors
Rectus femoris, iliopsoas
(Start propel limb)
—> Initiate hip flexion (clear ground)
Midstance, terminal stance (heel off) and preswing (toe off) = Ankle dorsiflexors
Inmate dorsiflexion (clear ground)
Name parts of swing phase
Initial and mid swing
Terminal swing
What is active during initial and mid swing and terminal swing
Hip flexors
Knee flexors
Ankle dorsiflexors
Hip adductors
(Flexion and extension)
Initial and mid swing, terminal swing phase = hip flexors
Rectus femoris, iliopsoas
—> Swing limb forward s(by flexing)
Initial and mid swing, terminal swing phase = knee flexors
Hamstrings
—> Flex knee to clear leg from ground
—> (as hip extensors = prepare for heel strike)
Initial and mid swing, terminal swing phase = ankle dorsiflexors
Dorsiflex to keep foot clear of ground
(But as close as possible to ground)
Initial and mid swing, terminal swing phase = hip adductors
—> Keep swing leg (right) close to stance leg
—> Assist in hip flexion (bringing swing leg forwards), from hyperextended position
What happens during stance phase
Hip abduction/adduction
During single support phase, body mass causes a tendency of the hips to drop/tilt towards contra lateral side, recruiting hip abductors on stance leg counters this and keeps centre of mas +/- level
- stance side hip abductors need to be active to control/prevent drop
Describe msucles during stance phase hip abduction/adduction
Hip abductors - gluteus medius/minimus, tfl
Stabilize/oppose hip adduction - pelvic tilt during single support phase
Describe what else happens during stance phase
Hip rotation In transverse plane
Describe what happens during stance phase - hip rotation
Early stance - hip opened
Midstance
To terminal stance - so close with medial rotation
Stance leg hip joint rotates medially - angle between pelvis and femur decreases
Assisted by gluteus medius and minimus - which are already in use to abduct hip
Describe what happens during swing phase - hip rotation
Lateral rotation begins - mid swing to terminal swing
So open up hip and throw leg forward
Hip rotates lateral, recruits lateral hip rotators (superior/inferior gemelli, internal and external obturator, quadratus femoris, piriformis )
Summary = gluteal region muscle functions
Control hip flexion - Maximus
Control pelvis tilt - medius, minimus and tfl
Decelerate limb
Summary = thigh and knee region muscle functions
Flex knee - clear substrate and move limb forwards, prepare for heel strike (hip extensors)
Flex hip to clear substrate and propel limb forwards
Control knee flexion to midstance, extend knee for heel strike
Summary = dorsiflexors of foot region muscle functions
Control plantarflexion - clear ground in loading response
Generate dorsiflexion during swing phase (plantar flexors), - clear substrate
Summary = leg and ankle region muscle functions
Control dorsiflexion through midstance, generate plantar flexion in push off (dorsiflexors)
Summary = foot region muscle functions
Stiffen foot and arches
Foot as level to max potential
What are abnormal/atypical gaits
Deviations from kinematic patterns of normal gait cycle
Describe why abnormal or atypical gaits
May be temporary - like Injury to permanent - palsy/amputation
May be unilateral or bilateral
May affect timing of gait cycle events and/or movements of limb segments and/or trunk
Often manifests in heel strike/midstance bc strongest gfr here
Abnormal gait - muscle weakness/paralysis - gluteus Maximus functions
Helps extend hip at end of swing and controls hip flexion due to ground reaction force/torque at initial contact
Abnormal gait - muscle weakness/paralysis - gluteus Maximus gait challenge
Weak/paralyzed gluteus Maximus (like injury to inf gluteal nerve) -
Cannot prevent/control hip flexor torque at initial contact/loading response, causing hip to buckle into flexion - on injured side
Abnormal gait - muscle weakness/paralysis - gluteus Maximus gait compensation
Quickly shift the trunk posteriorly,which moves teh grf line of action posterior to the hip joint, reducing or eliminating hip flexion torque due to grf
Abnormal gait - muscle weakness/paralysis - hip Abductors functions
Hip abductors control contra lateral drop of the pelvis - pelvic tilt, during single support in stance
Abnormal gait - muscle weakness/paralysis - hip Abductors challenge
Weak/paralyzed gluteus medius, minimus or tfl parents smooth control of pelvis tilt = leads to Abnormal amount of drop
Abnormal gait - muscle weakness/paralysis - hip Abductors compensation
Shift to the trunk over the stance leg, to reduce the torque created by the trunk during single support - throw weight over to supported side = minimize torque created by unsupported side
Abnormal gait - muscle weakness/paralysis - hip Abductors trendelenburg gait
Noticeable lateral shift of trunk over the stance leg and excessive pelvic drop = indicate weakness in hip abduction
Abnormal gait - muscle weakness/paralysis - knee extensors functions
Vastus group - controls knee flexion during loading response (due to grf being posterior to knee,creating a flexion torque)
Abnormal gait - muscle weakness/paralysis - quadriceps gait challenge
Weak/paralyzed quadriceps - if injury or compression of femoral nerve under inguinal ligament
Prevent smooth control of knee flexion during the loading response, leading to knee buckling
Abnormal gait - muscle weakness/paralysis - quadriceps gait Compensation
Rapidly shift the trunk forward over the stance leg (lurch), shifting grf into extension torque and/or physically push knee to lock into extension - pop knee
Abnormal gait - muscle weakness/paralysis - ankle dorsiflexors function
Control plantarflexion in the initial contact/loading response of stance
AND
Help clear foot/toes from ground throughout swing
Abnormal gait - muscle weakness/paralysis - ankle dorsiflexors challenge
Weak/paralyzed dorsiflexors - like if injury/compression of common Fibular nerve - compartment syndrome
Prevents smooth control of plantarflexion during the loading response, leading to foot slap and increased risk of tipping during swing due to drop foot
Abnormal gait - muscle weakness/paralysis - ankle dorsiflexors compensation
Exaggerate knee and hip flexion in early swing phase to clear ground = stoppage gait
May also shift to striking ground with midfoot or forefoot to about foot slap = equinus gait
