[Biomech Final] Gait Flashcards

1. stance
2. swing

1. Loading response (foot flat)
2. Mid Stance
3. Terminal Stance (heel off)
4. Pre-Swing (toe off)

1. initial swing (acceleration)
2. midswing (toe-off)
3. Terminal swing (deacceleration)

• Neutral @ ankle joint (no PF/DF)
• => 15* plantarflexion @ankle joint
• movement controlled
• Dorsiflexors(antagonist): eccentric contraction

• Foot flat: 15* flexion
• Midstance: 5* flexion
  • Net movement: 10* extension
• Mov AGAINST gravity = MOV produced
  • Quadriceps(antagonist): concentric contraction

• flexion
• quadriceps(eccentric): control movement

• flexion
• Hip flexors (concentric): produce movement

• flexion
• plantarflexion (concentric): produce movement

• Produces movement
• Moving against gravity

• Control movement
• moving towards gravity

• stabilizing movement

• 0%: (Right heel contact) // 50%: (left heel contact) // 100%: (right heel contact)
• Length: 144 cm
• Average human walking speed: 1.37 meter/sec

• @4-5mph

• less time in stance
• transition into running

1. double limb support (10%)
2. single limb support on RIGHT (40%)
3. Double limb support (10%)
4. Single limb support on LEFT (40%)

• helps with balance
• spend more time on swing

1. Heel contact (0%)
2. Foot flat (8%)
3. Midstance (30%)
4. Heel off (40%)
   1. PUSH OFF
5. toe-off (60%)
   1. early swing // mid swing // late swing
6. Heel contact (100%)

1. loading phase
2. mid-stance
3. terminal stance
4. pre-swing
5. initial swing
6. mid-swing
7. terminal swing

1. Initial contact (0%)
2. Opposite toe off (10%)
   1. mid-stance
3. Heel raise (30%)
4. Opposite initial contact (50%)
5. toe-off (60%)
   1. early swing // mid swing // late swing
6. Feet adjacent (73%)
7. Tibial vertical (87%)
8. Next initial contact (100%)

• 5cm displacement // HIGH BoB
  • Heel raise + midstance// switch to next leg
• 0cm displacement // LOW BOB
  • torque creates unilateral swing self-forward
  • SWING PHASE = NO CHANGE

• 4cm
  • total displacement (L+R)
• 2cm (each)
  • Right leg @30% (1st heel/switch off)
  • Left leg @80% (2nd heel/switch off)

1. Pelvis
2. Hip joint
3. knee joint
4. ankle joint

1. Posterior tilt (tilt back) = -5*
   1. heel strike -> heel plant
2. Anterior tilt (forward) = +*5
   1. heel plant -> heel raise -> knee bend
3. Posterior tilt (tilt back) = -5*
   1. knee bend -> full knee bend -> leg initial swing
4. Anterior tilt (forward) = +*5
   1. initial leg swing -> final swing

1. Flexion (+30*)
   1. heel strike down
2. Extension (-10*)
   1. heel raise / toe-off
3. Flexion (+30*)
   1. heel raise -> terminal swing

ALL FLEXION

1. @10*
   1. heel contact/strike
2. @20*
   1. foot flat // shock absorber
3. @2* (lowest)
   1. heel raise (end of stance // pre-swing)
4. @60* (highest)
   1. start of swing (ext->flex) // clear legs
5. @2* lowest
   1. terminal swing

1. Plantar flexion (-10*)
   1. toe up // heel strike
2. Dorsiflexion (10*)
   1. heel strike -> foot flat (propelling)
3. Plantarflexion (-20*)
   1. fast transfer of range // initial heel raise
4. Dorsiflexion (1*)
   1. initial knee bend + pre-swing
5. Plantar Flexion (-1*)
   1. leg clears and terminates swing

• Inverse relationship
• Potential Energy (HIGH)
  • B4 footplant -> B4 heel raise+knee bend -> heel strike
• Kinetic Energy (HIGH)
  • Foot complete plant -> midswing

• Pelvic + hip
• Subtalar joint

• Pelvic
  • -1.5 // Left side lower (heel contact = drop)
  • zero cm ( midstance, pitch up pelvis)
  • 1.5 // Left side higher (heel raise // pelvis raise)
• Hip
  • LOW Adduction: foot plant (cowboy mini lunge out => absorb weight)
  • HIGH Abduction: pre-swing (raise heel)

• Inversion (high)
  • land in lock
• Eversion (low)
  • unlock // pronation // shock absorption // transfer force
• Inversion (HIGH)
  • lock // producing force
  • rigid level for plantar flexion

1. Stance Phase (internal rot peak @foot flat)(external rot low @pre-swing)
   1. Pelvis (highest)
   2. Femur (dip @initial heel raise)
   3. Tibia (dip @initial heel raise)
2. Swing Phase (ext. rot low @pre-swing)(internal rot high @terminate swing)
   1. Pelvis (highest)
   2. Femur (dip @initial heel raise)
   3. Tibia (dip @initial heel raise)

1. LOW internal rot: heel strike
2. HIGH IR: inital knee bend (after foot plant)
3. LOW ER: midswing -> terminal swing
   1. shift weight to opposing foot you're going

...

• NEED HIGH ENERGY = to go slow
• NEED LOW ENERGY = to go fast

1. post cerebral accident (mod-severe residual deficits)
2. unilateral transfemoral amputation (w/ prosthesis)
   1. unilateral transtibial amputation (w/ prosthesis)
   2. immobilization 1 knee @45*
3. Immobilization of 1 hip
   1. immobilization of 1 knee @full extension
4. Immobilization of 1 ankle

1. horizontal plane pelvic rotation
   1. LOW down displacement of COM
2. sagittal plane ankle rotation
   1. LOW down displacement of COM
3. frontal plane pelvic rotation
   1. LOW UP displacement of COM
4. frontal plane hip rotation
   1. LOW s2s of COM

• Muscles
  • errector spinae // rector abdomins // gluteus maximus // iliopsoas // satorius // gluteus medius // gluteus minimus // tensor fascia lata // adductor magnus // adductor longus
• ON activation in the beginning
  • shock absorbtion
• ON at b4 MIDSTANCE
  
  • preparing to swing leg forward
• ON at terminal swing
  • need high trunk control / not fall foward

...

• hip extension: keeps from falling from flexion
• ON = heel contact + swing / heel raise
  • quad turns on // from extensor + flung forward // create flexion torque = need to counteract
  • when trunk control is highest
• OFF = midstance

• flexor
• gravity pulling down but not want flexor
• ON= kee pelvis stable during swing

• hip extensor
• need to create hip extension (4 shock absorption)

• 30% single-leg stance
• abduction (IT band)(PREVENT TIP OVER)

• at midstance -> heel off: needs to turn on calves to propel leg foward

• allowing the swing leg to advance toward the next step
• generating moments of force to control frontal plane movement.

• midstance
  • tibial progression stops // calf turns on + holds tibia stable
• heel off
  • gastrocnemius slows tibia down (tibia thrown forward)