Transcript GAIT - My CCSD

Sports Medicine II
SECTA
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Normal Gait =
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Series of rhythmical , alternating movements of the
trunk & limbs which result in the forward
progression of the center of gravity
series of ‘controlled falls’
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Gait Cycle =
Single sequence of functions by one limb
 Begins when reference foot contacts the ground
 Ends with subsequent floor contact of the same foot
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Step Length =
Distance between corresponding successive points
of heel contact of the opposite feet
 Rt step length = Lt step length (in normal gait)
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Stride Length =
Distance between successive points of heel contact of
the same foot
 Double the step length (in normal gait)
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Walking Base =
Side-to-side distance between the line of the two feet
 Also known as ‘stride width’
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Cadence =
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Number of steps per unit time
Normal: 100 – 115 steps/min
Cultural/social variations
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Velocity =
Distance covered by the body in unit time
 Usually measured in m/s
 Instantaneous velocity varies during the gait cycle
 Average velocity (m/min) = step length (m) x cadence
(steps/min)
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Comfortable Walking Speed (CWS) =
Least energy consumption per unit distance
 Average= 80 m/min (~ 5 km/h , ~ 3 mph)
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Phases:
(1)
Stance Phase:
reference limb
in contact
with the floor
(2) Swing Phase:
reference limb
not in contact
with the floor
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Support:
(1) Single Support: only one foot in contact with the floor
(2) Double Support: both feet in contact with floor
A. Stance phase:
1. Heel contact: ‘Initial contact’
2. Foot-flat: ‘Loading response’, initial contact of forefoot w. ground
3. Midstance: greater trochanter in alignment w. vertical bisector of foot
4. Heel-off: ‘Terminal stance’
5. Toe-off: ‘Pre-swing’
B. Swing phase:
1. Acceleration: ‘Initial swing’
2. Midswing: swinging limb overtakes the limb in stance
3. Deceleration: ‘Terminal swing’
Gait Cycle
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Time Frame:
A. Stance vs. Swing:
 Stance phase
 Swing phase
=
=
60% of gait cycle
40%
B. Single vs. Double support:
 Single support=
 Double support=
40% of gait cycle
20%
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With increasing walking speeds:
 Stance phase:
 Swing phase:
 Double support:
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Running:
decreases
increases
decreases
 By definition: walking without double support
 Ratio stance/swing reverses
 Double support disappears. ‘Double swing’
develops
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Center of Gravity (CG):
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midway between the hips
Few cm in front of S2
Least energy consumption if CG travels in
straight line
CG
A. Vertical displacement:
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Rhythmic up & down
movement
Highest point: midstance
Lowest point: double support
Average displacement: 5cm
Path: extremely smooth
sinusoidal curve
B. Lateral displacement:
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Rhythmic side-to-side
movement
Lateral limit: midstance
Average displacement: 5cm
Path: extremely smooth
sinusoidal curve
C. Overall displacement:
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Sum of vertical &
horizontal displacement
Figure ‘8’ movement of CG
as seen from AP view
Horizontal
plane
Vertical
plane
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Six optimizations used to minimize excursion
of CG in vertical & horizontal planes
Reduce significantly energy consumption of
ambulation
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(1) Pelvic rotation:
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Forward rotation of the pelvis in the horizontal plane approx. 8o
on the swing-phase side
Reduces the angle of hip flexion & extension
Enables a slightly longer step-length w/o further lowering of CG
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(2) Pelvic tilt:
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5o dip of the swinging side (i.e. hip adduction)
Reduces the height of the apex of the curve of CG
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(3) Knee flexion in stance phase:
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Approx. 20o dip
Shortens the leg in the middle of stance phase
Reduces the height of the apex of the curve of CG
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(4) Ankle mechanism:
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Lengthens the leg at heel contact
Smoothens the curve of CG
Reduces the lowering of CG
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(5) Foot mechanism:
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Lengthens the leg at toe-off as ankle moves from
dorsiflexion to plantarflexion
Smoothens the curve of CG
Reduces the lowering of CG
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(6) Lateral displacement of body:
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The normally narrow width of the walking base minimizes
the lateral displacement of CG
Reduced muscular energy consumption due to reduced
lateral acceleration & deceleration
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Forces which have the most significant
Influence are due to:
(1) gravity
(2) muscular contraction
(3) inertia
(4) floor reaction
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The force that the foot exerts
on the floor due to gravity &
inertia is opposed by the
ground reaction force
Ground reaction force (RF)
may be resolved into
horizontal (HF) & vertical
(VF) components.
Understanding joint position
& RF leads to understanding
of muscle activity during gait
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At initial heel-contact: ‘heel transient’
At heel-contact:
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Ankle: DF
Knee: Quad
Hip:
Glut. Max&Hamstrings
Initial HC
‘Heel transient’
Foot-Flat
HC
Mid-stance
Initial HC
‘HeelHeel-off
transient’
HC
Toe-off
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Low muscular demand:
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~ 20-25% max. muscle strength
A.
B.
C.
D.
E.
F.
Antalgic Gait
Lateral Trunk bending
Functional Leg-Length Discrepancy
Increased Walking Base
Inadequate Dorsiflexion Control
Excessive Knee Extension
“ Don’t walk behind me, I may not lead.
Don’t walk ahead of me, I may not follow.
Walk next to me and be my friend.”
Albert Camus
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Gait pattern in which stance phase on affected
side is shortened
Corresponding increase in stance on unaffected
side
Common causes: OA, Fx, tendinitis
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Trendelenberg gait
Usually unilateral
Bilateral = waddling gait
Common causes:
A. Painful hip
B. Hip abductor weakness
C. Leg-length discrepancy
D. Abnormal hip joint
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Swing leg: longer than stance leg
4 common compensations:
A. Circumduction
B. Hip hiking
C. Steppage
D. Vaulting
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Normal walking base: 5-10 cm
Common causes:
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Deformities
 Abducted hip
 Valgus knee
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Instability
 Cerebellar ataxia
 Proprioception deficits
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In stance phase (Heel contact – Foot flat):
Foot slap
In swing phase (mid-swing):
Toe drag
Causes:
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Weak Tibialis Ant.
Spastic plantarflexors
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Loss of normal knee flexion during stance
phase
Knee may go into hyperextension
Genu recurvatum: hyperextension deformity of
knee
Common causes:
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Quadriceps weakness (mid-stance)
Quadriceps spasticity (mid-stance)
Knee flexor weakness (end-stance)
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Pronation is the
movement of the subtalar
joint (between the talus
and calcaneus) into:
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Eversion (turning the sole
outwards)
Dorsiflexion (pointing
the toes upwards) and
Abduction (pointing the
toes out to the side
Overpronation is often
recognized as a flattening
or rolling in of the foot
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Shin Splints
Anterior Compartment Syndrome
Patello-femoral Pain Sydrome
Plantar Fasciitis
Tarsal tunnel Syndrome
Bunions (Hallux Valgus)
Achilles Tendonitis
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Supination is a movement
at the foot which is a
necessary movement for
walking and running
amongst other activities
Supination is the
movement of the subtalar
joint (between the talus
and calcaneus) into:
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Inversion (turning the sole
inwards)
Plantarflexion (pointing
the toes away from you)
and
Adduction (pointing the
toes across your body).
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Oversupination (hyper-supination) is far more
rare than overpronation and causes problems
for runners and other athletes, as in this
position the foot is less able to provide shock
absorption.
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Shin Splints
Plantar Fasciitis
Ankle Sprains
Stress fractures of the tibia, calcaneus and
metatarsals
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Propulsive gait -- a stooped, stiff posture with
the head and neck bent forward
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Carbon monoxide poisoning
Manganese poisoning
Parkinson’s disease
Use of certain drugs including phenothiazines,
haloperidol, thiothixene, loxapine, and
metoclopramide (usually drug effects are temporary)
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Scissors gait -- legs flexed slightly at the hips and knees like
crouching, with the knees and thighs hitting or crossing in a
scissors-like movement
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Brain abscess
Brain or head trauma
Brain tumor
Cerebrovascular accident
Cerebral palsy
Cervical spondylosis
Liver failure
Multiple sclerosis
Spinal cord trauma
Spinal cord tumor
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Spastic gait -- a stiff, foot-dragging walk caused by
a long muscle contraction on one side
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Brain abscess
Brain or head trauma
Brain tumor
Cerebrovascular accident
Cerebral palsy
Cervical spondylosis
Liver failure
Multiple sclerosis
Spinal cord trauma
Spinal cord tumor
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Steppage gait -- foot drop where the foot hangs
with the toes pointing down, causing the toes to
scrape the ground while walking, requiring
someone to lift the leg higher than normal when
walking
Herniated lumbar disk
 Multiple sclerosis
 Muscle weakness of the tibia
 Spinal cord injury
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Waddling gait -- a duck-like walk that may
appear in childhood or later in life
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Muscle disease (myopathy)
Spinal muscle atrophy
Muscular dystropy
Congenital hip dysplasia
Ataxic or broad-based gait
Alcohol intoxication
Brain injury
Damage to nerve cells in the cerebellum of the brain
(cerebellar degeneration)
 Medications (phenytoin and other seizure medications)
 Polyneuropathy (damage to many nerves, as occurs with
diabetes)
 Stroke
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