Biomechanics of Gait Initiation and Termination

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Biomechanics of Gait Initiation and Termination

• D. Gordon E. Robertson, PhD, FCSB
• Richard Smith. PhD, U. Sydney
• Nader Farapour, PhD, U. Tehran
• Natasha Kyle
• Joe Lynch
• Biomechanics, Laboratory,
• School of Human Kinetics,
• University of Ottawa, Ottawa, Canada

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Initiation of Gait Events
Quiet stance
First toe-off (lead-leg)
Second toe-off (trail-leg)
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ResultsCentres of Pressure
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Biomechanics of Ramp Ascent and Descent

• D. Gordon E. Robertson, PhD, FCSB
• Robyn Wharf
• Andrew Post
• Biomechanics, Laboratory,
• School of Human Kinetics,
• University of Ottawa, Ottawa, Canada

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Ramp Ascent Study(Robyn Wharf)

• level, 3-, 6- and 9-degree inclines
• one step before ramp
• opposite leg on ramp
• 2nd step on ramp

Force platforms
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Ramp Ascent
Moments
Powers
hip

• very few differences in the moments of force
• powers were more diagnostic
• level walking and 3-degrees almost same
• 6- and 9-degree inclines were sig. different

knee
ankle
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Biomechanics of Stair Ascent and Descent

• D. Gordon E. Robertson, PhD, FCSB
• Tyler Cluff
• François D. Beaulieu
• Andrew Post
• Stefan Potozny
• Biomechanics, Laboratory,
• School of Human Kinetics,
• University of Ottawa, Ottawa, Canada

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Motion Analysis Tools
Reflective markers
Infrared cameras and EMGs
Force platforms
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Laboratory Stairs

• Step height 20 cm
• Step tread 30 cm
• Railings 91 cm
• Height and tread are adjustable

Force platforms
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Backwards Stair Descent
Down Two Stairs Backwards to Landing
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Discussion
Benefits of Backwards Stair Descent

• Centre of pressure and centre of gravity are
  farther from edge of stairs
• If tripping occurs person falls into stairs not
  down stairs
• Person will be more inclined to use handrails
• Moments and powers were smaller than forwards but
  larger than walking
• No concentric ankle power needed (e.g.,
  B-K amputees)

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Discussion
Concerns with Backwards Stair Descent

• Problems with seeing next step and landing
• Unconventional therefore may affect compliance
• Does require railings for most people
• Irregular stairs may be problematic

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Il Castillo, Chichen Itza, Mexico
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Ballet Biomechanics

• grand jette
• jumping mechanics
• simulation

• pirouette

• fouette