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The Gait Cycle - walking
- wider stance
- shorter stride
- bipedal phase
- no flight phase
- approximately 60% stance phase
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The Gait Cycle - running
- narrow stance
- longer stride
- never in a bipedal phase
- airborne phase
- approximately 30% stance phase
- increased GRF
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Breakdown of Gait (walking)
- Stance phase - often termed the "active phase"; accounts for 60% of gait, closed chain
- Swing phase - often termed "recovery phase"; accounts for 40% of gait, open chain
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Initial Contact of stance phase
- heel contacts with ground at lateral aspect
- foot in supinated position (5 degrees)
- gradual decent of foot as body weight shifted
- Comprises of 20% of total gait cycle
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Loading Response in stance phase
- eccentric contractions of lower leg and foot to decelerate and control foot motion
- Ground Reaction Forces are absorbed here
- Foot moves to a pronated position (10 degrees)
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Midstance of stance phase
- body moves over the top of foot
- foot is pronated but moves toward supination
- ground contact moves from lateral foot to medial foot at the metatarsal heads
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Terminal Stance of stance phase
- unipod to bipod transition at end of phase
- continued supination with ground contact moving along the 1st ray
- body ahead of foot with concentric contractions pushing it forward to begin another phase
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Preswing of stance phase
- bipod phase as other foot continues with heel contact
- ground contact is through the great toe
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Initial Swing of swing phase
- muscle activity concentrates in thigh and hip as leg is lifted off ground
- foot recovers from preswing and clears the ground
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Midswing of swing phase
- mid-point of swing
- momentum carries leg as foot prepares for inital contact with ground in next cycle
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Terminal Swing in swing phase
- knee extends fully
- foot is isometrically stabilized in supination awaiting heel contact
- foot is in front of body once again
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Weight Bearing Static Assessment
- hip width stance
- assess rearfoot alignment
- navicular height
- 1st Ray alignment
- Tibial alignment
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Non-Weight Bearing Static Assessment
- Prone position - subtalar neutral, rearfoot and midfoot alignment, callus/blister/shoe wear
- Seated position - navicular height, midfoot and toe alignment
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Ground Reaction Forces
- May be horizontal or vertical
- running can generate 2-3 times BW (the wider the stride, the greater the GRF)
- GRF's affect soft and osseous tissues
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Acustep
- records pressure distributions
- requires assessment to still be done
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Static View of Gait Assessment
- lateral, anterior, and posterior
- hindfoot, forefoot, and toes
- spacing of feet and toes
- possibly check with squat
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Dynamic View of Gait Assessment
- person's normal gait must be attempted
- concentrate on Stance phase
- limb position
- ROM
- speed of motion
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Biomechanical Process of Initial Contact
- 5 degrees of supination at subtalar joint
- eccentric dorsiflexors/Inactive plantarflexors
- full knee extension
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Biomechanical Process of Loading Response
- Movement to 10 degrees of pronation
- Eccentric dorsiflexors/Concentric plantarflexors
- Near flat foot
- Center of gravity still behind foot
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Biomechanical Process of Midstance
- Pronation ceases and movement back toward supination begins
- Dorsiflexors and plantarflexors are isometric stabilizers
- Majority of weight is at metatarsal heads
- Center of gravity is above foot
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Biomechanical Process of Terminal Stance
- Continued movement of supination with hindfoot
- Dorsiflexors now inactive/Plantarflexors concentric
- Ground contact mostly with met. heads and toes
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Biomechanical Process of Preswing
- Mild supination continues
- Weight transference at 80% great toe
- Lift off from ground and into swing phase
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