Gait Flashcards
(98 cards)
1
Q
gait definition
A
a repeating process of intentional, controlled falls
- also intentionally putting ourselves off balance to later catch ourself
2
Q
line of progression
A
the hypothetical line corresponding to the direction you’re following as you walk
- the average between each leg LOP
3
Q
double vs single support
A
- double = both legs bearing weight
- single = one leg bears weight
4
Q
stance phase of gait
A
from IC to TO
- stand on limb of interest
- takes up 60% of gait cycle for one limb
5
Q
swing phase of gait
A
from TO to IC
- limb of interest is moving
- takes up other 40% of gait cycle for one limb
6
Q
phases of stance
A
- loading
- mid-stance
- terminal stance
- pre-swing
7
Q
loading phase
A
1st phase of stance
- 0-10% of gait cycle
- from IC to OTO
- absorb energy and stabilize limb, making sure it’s ready to absorb weight
8
Q
midstance phase
A
2nd phase of stance
- 10-40% of gait cycle
- a transitional phase, NOT a moment in time
- OTO (when we finish loading) to HR
- COM passes over fixed foot - we start to fall as we run out of room and our heel rises marking the end of this phase
9
Q
terminal stance phase
A
3rd phase of stance
- 40-50% of gait cycle
- HR to OIC
- COM moves in front of forefoot - more falling
10
Q
pre-swing phase
A
4th phase of stance
- 50-60% of gait cycle
- from OIC to TO
- unloading weight from leg of interest to the other limb so we can prepare to swing our interest limb
11
Q
phases of swing
A
- initial swing
- mid-swing
- terminal swing
12
Q
dual pendulum motion of leg
A
- describes hip as 1st pendulum and knee as 2nd pendulum
- motion used to advance limb: hip swings leg forward and knee flicks out at the end
13
Q
initial swing phase
A
1st phase of swing
- 10-15% of gait cycle
- TO to FA
- swinging leg with the intention of accelerating the limb and clearing the ground
- minimum foot clearance considered here
14
Q
mid swing phase
A
2nd phase of swing
- 10-15% of gait cycle
- FA to TV
- goal is to accelerate limb of interest
15
Q
terminal swing phase
A
3rd phase of swing
- 10-15% of gait cycle
- TV to IC
- goal is to decelerate limb of interest before it goes into stance phase again
16
Q
foot adjacent
A
when swinging leg of interest, the point where both feet are in line with one another
17
Q
minimum foot clearance
A
- the very small amount of space required for someone’s foot of interest to clear the ground
- part of the initial swing phase
- normal is 1.2-1.5 cm
- not very much room for people with pathologies that cause them to not meet the MFC
18
Q
tibia vertical
A
where tibia is vertical in space - straight up and down
19
Q
temporal and spacial parameters (TSP)
- what are they
- name them
A
things we can measure and compare to normal values:
- stride length
- toe-out angle
- step width/walking base
- step length
- cadence
- speed
20
Q
stride length
A
- the total distance you cover with the same foot in anterior to posterior direction
- the swing and stance phases for one foot
21
Q
toe-out angle
A
- the angle formed by the line of progression to the reference line of the foot
- normal is 7°
22
Q
step width/walking base
A
- horizontal distance between the centres of 2 heels
- normal is 10-15 cm
- any values greater than normal make walking inefficient (ex. morbid obesity)
23
Q
step length
A
- distance from heel to heel between left and right feet in anterior to posterior direction
- normal is 65-70cm
24
Q
cadence
A
- step frequency
- normal is 110-115 steps/min
25
speed
- can be calculated - see notes and practice
| - comfortable walking speed for normal adult is 1.2-1.4 m/s or 4.5-5 km/h
26
what is the purpose of pronation when walking
| - what does it look like in terms of rearfoot and forefoot
- helps absorb/soften energy of impact
- rearfoot eversion starts pronation process
- forefoot abduction - toes separate and point more laterally as talus comes down and forward
27
what is the purpose of supination when walking
- makes the foot a rigid lever for propulsion
- rearfoot inversion
- forefoot adduction - toes point more medially which brings the foot back together so it can be rigid
28
loading phase actions of:
- ankle
- foot
- knee
- hip
start steady then absorb
- ankle - heel rocker, PF 5-10°
- foot - slightly supinated before loading, switched to more pronated
- knee - flexion to 15°
- hip - flexed 30° at IC
29
midstance phase actions of:
- foot
- ankle
- knee
- hip
COM passes over centre of foot but remains within the vertical margins of the foot
- foot - shifts to supinated
- ankle - ankle rocker, DF to peak 10° as COM passes
- knee - starts slightly flexed and finishes in full extension
- hip - extends slightly
30
terminal stance phase actions of:
- MTP joints
- foot
- ankle
- knee
- hip
COM moves beyond toes to cause falling
- MTP joints - forefoot rocker mechanism - MTPJ extend as heel rises
- foot - supinated
- ankle - PF to push off ground
- knee - slight flexion
- hip - extends to peak 20°
31
pre-swing phase actions of:
- foot
- ankle
- knee
- hip
finishing propulsion and unloading interest limb
- foot - supinated
- ankle - PF to peak 20°
- knee - flexion approaching 30-40°
- hip - flexes to approach neutral (coming out of extension)
32
swing phase actions of:
- foot
- ankle
- knee
- hip
- foot - supinated
- ankle - DF to neutral for foot clearance
- knee - flexes to 60° during initial swing then extends after FA
- hip - flexion to advance limb
33
COM movement in gait vertical trajectory
- highest point?
- lowest point?
- described as inverted pendulum that rises and falls 4-5 cm
- highest point is middle of midstance as COM is right over top of foot
- lowest point in double support phase IC or approaching OTO
34
COM movement in gait medial-lateral trajectories
- most medial?
- most lateral?
- COM moves 4-5 cm medial-lateral as we walk
- most lateral - single support all weight shifts to one foot
- most medial - double support phase
35
head, arms, trunk (HAT) motion
- analogy: HAT are passengers along for the ride and legs are the locomotor that makes things happen
- HAT accounts for 2/3 of body mass
36
arm swing with gait (HAT rotation)
- arm swings with opposite leg
- we see opposing pelvic rotation of the swinging arm
- as we walk, shoulders turn 10° with each step
37
pelvic rotation transverse plane with regards to the hip extended
- pelvis rotates to same side as extended
| ex. L foot in front makes pelvis look to face the right (and the R hip is extended)
38
pelvis motion in frontal plane during gait
refers to left or right tilt of pelvis
- hiking shortens functional reach
- dropping increases functional reach
- look at opposite side of pelvis as the leg of interest
- total arc is approximately 10° of hike and drop
39
neutral and most dropped position of pelvic tilt in gait
- neutral - double support
| - most dropped in single support
40
ground reaction force (GRF)
- how the ground reacts in response to whatever we do to it
| - we imagine that the GRF is acting on one part of the foot which is the centre of pressure
41
GRF vector
- runs from centre of pressure to COM
| - as we move through stance phase, GRF vector starts at the heel and points back, ends at the toe pointing forward
42
GRF through loading phase
- think of GRF vector as an elastic bend around each joint
- GRF runs post to ankle, post to knee and anterior to hip
- if knee extensors are active but flexion is happening we have a ECC contraction but it is necessary to keep us from collapsing to the ground
43
GRF through mid-stance phase
| this is weird see notes
- GRF is anterior to ankle, tries to DF and PF group fights
- GRF is anterior to knee, trying to extend but since vector is so close to joint centre, not much motion happens
- GRF is posterior to hip, tries to extend but is also close to joint centre here
44
GRF through terminal stance and pre-swing
- GRF is anterior to ankle, wants DF, turns on PF
- GRF is post to knee, wants flexion, turns on extensors
- GRF is posterior to hip, wants extension, turns on flexors
45
general rules with GRF and ECC/CON absorbing and propelling
- absorbing is almost always ECC
| - propelling is almost always CON
46
muscular activity during initial swing and midswing
- aim to accelerate limb
- start double pendulum with hip flexors active
- to clear ground: DF of ankle and hip flexors
- start knee flexors to help clear ground
47
muscular activity during terminal swing
- aim to slow down the swing and finish double pendulum
- using eccentric contractions of hip extensors, knee flexors
- DF of ankle to make contact in DF position
48
reasons to take detours in movement
- skeletal architecture
- muscle weakness or paralysis
- neurological issues - ex. balance or coordination
- contracture
- spasticity
- pain (antalgic gait)
49
contracture
- permanent shortening of a muscle or joint
| - a joint seems to be stuck in a certain position
50
spasticity
- dysfunctional stretch reflex = exaggerated reflexes
- you can slowly try to pry a joint open so as not to trigger the reflex
- reflective of a larger neurological condition
51
examples of neurological conditions
- cerebral palsy
- stroke/cerebrovascular accidents
- multiple sclerosis
- parkinson's disease
- cerebellar disease
- peripheral neuropathies (affect nerves outside CNS)
52
examples of orthopaedic conditions
- legge-calve-perthes
- slipped capital femoral epiphysis
- amputation and prostheses
- osteoarthritis
- leg length discrepancies
- talipes equinovarus (club foot)
53
legge-calve-perthes (LCP)
a paediatric condition
- associated with vascular necrosis of head and neck of femur that makes growth plate degenerate and we see rotational deficiency
54
slipped capital femoral epiphysis (SCFE)
a paediatric condition
- at head of femur, there's the growth plate (epiphysis), slipped refers to how it's almost as if the epiphysis slides out of place
- is very painful
55
talipes equinovarus (club foot)
- a malformation of the foot within the first few months of birth
- observe foot turned in - after baby is born, it should be curled up but eventually uncurl
- very significant varus position
- in places where there's no medical care, people grow up with club foot and it has an impact on their ability to walk, work and live for themselves
56
Parkinsonian gait
- bradiokinesia - short step length, narrow base of support
- rigid, stooped, shuffling
- hypokinesia of all extremities - less awareness of movement
- freezing episodes, can't seem to move when they reach a barrier (square on the floor, doorway)
- turning, changing directions very difficult
- once they get moving, they seem to be okay
- laying out visual or auditory cues that prompt steps help trigger normal gait pattern during off phase
- in on phase, gait seems much more normal, see arms swinging again
57
hemiplegia gait
- a result of paralysis or weakness on one side - altered function on one half of the body
- cerebral palsy or result of a stroke
- usually no arm swing - elbow flexed, shoulder adducted and hand in fist
- foot dropped in PF position, stiff knee extension makes ground clearance difficult so circumduction of hip is a detour to accomodate
58
gait of cerebral palsy
- non-progressive motor impairments a result of damage to CNS during early development (not just motor)
- often interventions are in paediatric stages
- spasticity affects different parts of the body
3 spasticity-induced patterns:
- equinus gait
- scissors gait
- crouch gait
59
equinus gait
- a gait pattern/detour for CP
- child walks with spasticity of PF so they walk on their toes with no heel contact with ground
- use orthoses to help improve motion - can be braced to allow for DF
60
scissors gait
- a gait pattern/detour for CP
- spasticity affecting adductors of hip
- can occur in conjunction with equinus gait
- adductors bring leg across and one foot often contacts the other, can't bring foot very far in front so very short step length
- treated by training and bracing ankle into DF position to help gain function
61
crouch gait
- a gait pattern/detour for CP
- spasticity of hamstrings and also affects hip flexors
- looks like crouching
- flat foot, knee flexed, hip flexed slightly
- short stride length, no equinus and not as much flexion in swing phase
62
cerebellar ataxic gait
- very broadly connected to any conditions involving cerebellum
- cerebellar damage results in loss of control and coordination of voluntary body movements
- influences balance and gait as well as upper extremity and smoothness of eye movement
- drunken appearance
- taking very wide steps (wide base of support to help balance), jerky movement, intensity and smoothness of contraction is challenged
- trunk movement also when COM moves because of jerky movements
63
myopathic gait
- what does it look like?
- what if it's not myopathic?
- a pathology specifically affects muscle function in some way, not always nerve damage ex. DMD
- alternating lateral trunk leans, widened walking base, waddling, sometimes valgus knee
- if not myopathic: pregnancy or hip dysplasia/osteoarthritis of hip: waddling happens when person leans trunk toward hip to make up for hip adductor weakness
64
anterior trunk lean gait
- forward flexed trunk position in early stance when a difference is observed between top and bottom
- an adaptation, not usually neurological
- weak knee extensors or tight/short hip flexors
65
posterior trunk lean gait
- slightly less common than anterior trunk lean
- early stance (after IC) - caused by weak hip flexors when GRF is close to centre, hip flexors prevent us from dropping into ground and if we shift trunk back, it makes GRF easier to handle
- swing phase (more common) - caused by weak hip flexors or spastic hip extensors - since we need to use hip flexors to swing leg forward, weakness/spasticity makes this difficult so people try to whip leg through flexion of hip instead
66
Trendelenberg gait
- fairly common (ex. grandparents)
- opposite side of pelvis drops, lateral shift to the same side
- associated with weak hip abductors (dysplasia, osteoarthritis) when gravity tries to adduct hip, pelvis drops down and greater trochanter seems to shift sideways and tells us that the opposite hip is affected
67
compensated trendelenberg gait
- weakness of hip abductors can lead to adopting lateral trunk lean towards pathological side, making pelvis drop less and makes it easier for hip abductors
- usually unilateral
68
circumduction as a gait detour
- a strategy to clear the ground if you can't normally flex hip, flex knee, or DF ankle
- a semi-circular path taken by the swing leg
- instead of leg following through in normal swing plane, it moves in hemispheral way
69
hiking as a gait detour
- a strategy to clear the ground if you can't normally flex hip, flex knee, or DF ankle
- lifting the swing side of the pelvis up
- in single stance, you stand on stance leg and opposite side drops down, but to allow for clearance, we see opposite side hike up to make enough vertical space to allow clearance
70
toe-in gait
- a result of tibial torsion, femoral torsion, hip dysplasia (malformation of acetabulum) so often presents in early skeletal development (often 2 year olds)
- may have excessive femoral angle of antiversion
- can increase risk of tripping
- in skeletally immature populations, can guide development of femur so it matures straight, bracing
- toe-out may be associated with hip joint pathology
71
steppage gait/marching strategy
- exaggerated hip and knee flexion, flat foot with no heel rocker as ankle does not DF well, sometimes see full dropped foot if full paralysis
- aims to increase foot clearance during swing
- knee and hip compensate for DF of foot
72
knee hyperextension - gait detour
- stance phase compensation for weak knee extensors by putting GRF vector in front of knee joint so there's less demand on knee extensors
- often combined with anterior trunk lean
- hyperextended knee relies on passive tissues of knee but moves GRF vector in front of knee
- COM leaned very forward on foot
73
vaulting gait
- excessive ankle PF on stance leg with excessive vertical motion so rather than normal PF, we see heel kick off really fast
- stance leg modification to help swing leg clear the ground
- person has a bounce to gait when walking
74
normal walking speed is what
1.2-1.4 m/s
75
running speed and transition speed from walking
transition from walking to running at 2-3 m/s and can still be counted as running as high as 8 m/s
- running has a flight phase
76
sprinting speed and transition speed from running
transitions at 8 m/s and fastest known is 12.5 m/s
77
temporal spatial effects of running
- no more double support - only ever in single support or flight/float phase
- decrease stance phase to <50% since we spend less time on the ground
- contact time, stride length, and cadence all change as speed increases
78
GRF and speed
- higher speed has greater peak GRF
- slowly running has longer contact time and peak GRF is smaller
- GRF and running speed is important when considering running injuries
79
stride length and running velocity
- starting running slowly, we can increase stride length but only to a certain point
- then the only factor that increases speed will be to increase our stride frequency, however we can only do this to a point as well
- ie. increasing both stride length and stride frequency increase running velocity
80
how do kinematics change as running speed increases?
- at IC
- during impact absorption
- during swing
- overall muscle activity
- arm swing
- at IC, increase hip flexion and ankle DF
- increase knee flexion for impact absorption
- during swing, increase hip and knee flexion - shortens moment of inertia :)
- overall muscle activity increases with more co-contraction
- increase arm swing with more hip rotation (counter swing of arms is greater)
81
what happens to knee flexion with faster running speed
- goes to 45° in stance
| - peak velocity in swing has 90° flexion or more
82
what happens to hip flexion with faster running speed
- more hip flexion when landing: 40°
83
types of foot strike patterns with running
1. rearfoot strike
2. forefoot strike
3. midfoot strike
84
rearfoot strike
- primary contact point with heel first
- force plate VGRF sees 2 peaks - first peak shows heel strike which is transient and represents exclusively the foot striking the ground
85
forefoot strike
- primary contact point with forefoot during IC
86
midfoot strike
- landing with balanced heel, midfoot and forefoot landing about the same time
- land with foot essentially flat with weight evenly distributed
- VGRF on force plate shows midfoot doesn't have the same impact/ first peak that rearfoot strike does, suggests that midfoot strike is more smooth
87
elite half-marathoners foot strike patterns
- generally 75% use RFS and 24% use MFS
| - top performers: 60% RFS and 35% MFS, so slight shift to midfoot strike
88
recreational marathoners foot strike patterns
- 89% use RFS and 3% use MFS
89
sprinters foot strike patterns
- forefoot strike, run on tiptoes
90
what foot strike pattern has the highest loading rates
RFS has faster loading speed which could be more challenging to tissues
91
what foot strike pattern has the highest peak forces
FFS highest forces on impact
92
when comparing RFS to FFS, what has more patellarfemoral joint loading and what has more achilles loading
- RFS has more patellarfemoral loading than FFS
| - FFS has more achilles loading
93
RFS vs FFS and repetitive stress injury rates
RFS runners have 2x as many repetitive stress injuries as FFS runners
94
common running errors at the hip
- excessive pelvic drop (linked to abductor weakness and valgus knee)
- hip adduction
- femoral internal rotation
95
common running error foot - excessive pronation
| explain
- with excessive pronation, see rearfoot eversion and tibial internal rotation
- foot not an effective lever for pushing off
- foot not effective at ECC loading - dropping very fast
- axis of tibia with pronation and eversion makes tibia rotate medially - muscle imbalance between internal and external rotators of tibia
96
common running error foot - limited pronation
| explain
- with limited pronation, see rearfoot eversion and tibia is externally rotatied
- foot stays more supinated and not managing eccentric loads by absorbing force on impact
- look at muscular imbalances (weakness/tightness) of tibia rotators
97
common running error foot - heel whip
| explain
- can be medial or lateral, but medial is most common
- reflects torsional stress of limb - somewhere from heel to hip
- look at side of foot, in stance phase, there will be little turnout (neutral while in contact with ground), but more toe out in swing phase
- rotational stress when in contact with the ground gets released by trying to rotate the foot
98
over-striding
- a common running error
- reaching more in front and less behind - GRF comes up and back which "brakes" against up and slows us down excessively
- we want more stride length in the back to harness GRF to propel us forward
- has more impact on running performance than injury risk
