Week 1 Gait Flashcards
Orthosis
an external appliance worn to restrict or assist motion or to transfer load from one area to another
Synonym for orthosis
brace
Plural for orthosis
orthoses
Prothesis
a replacement of all or part of the leg or arm
Plural of prothesis
protheses
Certified orthotist/prothetis
bachelor degree in O&P
or
post grad O&P
and
clinical residency
CPO responsibilities
Patient assessment, formulation of treatment plan, patient follow- up
Select appropriate device and materials
Design, fabricate, and fit orthoses
Design, fabricate and fit prostheses
Demonstrate how to use device to patient
O&P Assistant
Practice under guidance of CPO, assist with O&P procedures and tasks related to patient mgmt.
Fabricates, repairs, and maintenance of devices
American Board for Certification in O&P:
High school degree (or higher) AND 3 semester hours in human anatomy, general/fundament physics, and medical terminology AND 1-1.5 yrs of clinical experience under CPO
O&P Technicians
Fabricates, repairs, and maintains orthoses and/or prostheses. Must be proficient in current fabricating techniques, familiar with material properties and skilled in use of necessary equipment
American Board for Certification in O&P:
Completion of accredited program OR high school degree (or higher) and 2 yrs experience under CPO or assistant
PTs Role in O&P
Assessment for identified purposes
Preparation for use
Evaluation of fit
Education in fit and training in use (donning/doffing)
Gait Training, Transfer Training, High-Level Training
Assessment and quantification of functional benefits and uses
Level I code
current procedural terminology
Level II code
Codes that identify services, products and supplies not included in CPT codes, such as prosthetic and orthotics. “L- Codes”
heel strike
initial contact
foot flat
loading response
midstance
midstance
heel off
terminal stance
toe off
pre-swing
Acceleration
initial swing
midswing
midswing
deceleration
terminal stance
percentage of gait cycle
100
stance phase percentage
60
swing phase percentage
40
initial contact percentage
0
loading response percentage
0-10
mid stance percentage
10-30
terminal stance percentage
30-50
pre swing percentage
50-60
initial swing percentage
60-73
mid swing percentage
73-87
terminal swing percentage
87-100
What are the phases of stance phase
initial contact
loading response
mid stance
terminal stance
pre swing
What are the phase of swing phase
initial swing
mid stance
terminal swing
velocity
rate of linear forward motion of the body (m/sec)
Cadence
number of steps taken per unit of time (steps/min)
Stride length
heel strike to ipsilateral heel strike
step length
heel strike to contralateral heel strike
Step width
width of base of support
sagittal plane
flx/ext
frontal plane
abd/add
Transverse plane
rotation
What is the sixth vital sign
walking speed
1 stride =
1 gait cycle
Primary forces that control walking
internal muscle forces
gravity (body weight)
air resistance
GFRs
GRFs in gait
forces applied to the body by the ground, opposing forces applied to the ground during a step
External forces
produce external torque/movement
GRF
can measure with force plates
Internal forces
produces internal torque/movement
response to external torque by GRF
Can control or generate movement
Possible contributions from ligaments, joint capsules, muscles, or bony structures
movement = torque
potential for a force, acting a distance from the axis of rotation, to produce rotation of a segment
Torque =
force x movement arm
Movement arm
perpendicular distance btw axis of rotation and line of action of the force
Internal torque =
IF x Ima
External Torque =
EF x Ema
static equilibrium
INT = EXT
Functional task of stance
weight acceptance
single limb support
Functional task of Swing
foot clearance
single limb advancement
Weight acceptance
initial contact
loading response
Initial contact objectives
start of 1st rocker
impact deceleration
loading response objects
shock absorption
weight-bearing stability
preservation of progression
IC - ankle
held at neutral by pre-tibial muscles
IC - knee
full ext
provide stability
IC - hip
peak flexion (20 deg)
positioned for optimal fwd progression and stability
IC critical event
heel contact
Muscle activity for hip stability in IC
hamstrings and gluteals
Muscle activity for knee stability in IC
qaudricep
What counterbalances PF movement in IC
Pre-tibialis
Shock is absorbed while FWD momentum is preserved
Loading respones
LR - ankle
pre-tibial muscles eccentrically control PF
subtalar eversion
1st rocker
LR - knee
20 deg of flx for shock absorption
quadriceps to control knee flx movement
LR - hip
maintained in flex (20 deg)
hip ext active to stability
LR critical events
pre-tibial muscles eccentrical control PF
quads active to control knee flexion movement
hip extensors active to stability
LR muscles for hip stability
hamstrings and gluteals
LR muscles to counterbalance flexion movement
quadriceps
LR muscles at ankle
pre-tibialis to counterbalance PF moment. Calf for stance stability
Single limb support
midstance
terminal stance
Midstance objectives
progression over stationary foot
limb and trunk stability
terminal stance objective
progression of body beyond the supporting foot
limb and trunk stability
Body progresses over foot in controlled manner. Contralateral limb provides momentum
Midstance
Mst - ankle
DF controlled eccentrically by gastrocnemius and soleus
ankle 2nd rocker
Mst - knee
extension
Mst - hip
neutral
Mst critical event
DF controlled eccentrically by gastrocnemius and soleus
Mst muscles for stance stability
quadriceps
Mst calf muscle
for stance stability and to counterbalance DF movement
Tst - ankle
Noted by heel rise
forefoot 3rd rocker
decline in gastro/soleus mm activity
Tst - knee
full ext to maximum step length
Tst - hip
20 deg of apparent hyperextension for maximum step length
Tst critical event
Trailing limb
Tst calf
counterbalance DF movement
1st rocker
arc of ankle PF right after IC
2nd Rocker
Tibial progression FWD during midstance
3rd rocker
forefoot DF as heel rises
4th rocker
tibia continues to progress fwd as great toe extends
Swing limb advancement
preswing
initial swing
midswing
terminal stance
Pre swing objective
position of limb for swing
accelerate progression
Psw critical event
passive knee flexion 40 deg
Psw hip flexors
counterbalance extension movement and initate swing
Psw calf
counterbalance DF movement
Psw pre-tibialis
foot clearance
initial swing objectives
foot clearance
advancement of the limb from the trailing limb position
Isw critical events
Peak knee flexion for toe clearance \15 deg of hip flx
Msw critical event
ankle neutral to slight DF
Tsw Critical event
knee extension to neutral
Midswing objectives
limb advancement
foot clearance
terminal swing objectives
complete limb advancement
Forefoot remains on ground. Knee rapidly while weight is shifted to other limb.
Pre-swing
Psw - ankle
2nd arc of PF (15 deg)
toe rocker
no gastroc/soleus mm activity
Psw - knee
passive knee flx (40 deg)
Prepares limb for toe clearance
Psw - hip
10 deg of apparent hyperextension
Isw - ankle
nearly neutral for foot clearance
Isw - knee
peak flexion (60 deg) for toe clearance
Peak mm activity of biceps femoris short head, sartorius, and gracilis
Isw - hip
15 deg of flex
Peak mm activty of gracilis and sartorius
Msw - ankle
Neutral to slight DF
Msw - knee
passive ext caused by the momentum of hip flx
Msw - hip
peak flx (25 deg)
Leg reaches out to achieve step length. Preparation for IC.
Terminal swing
Tsw - ankle
at neutral to prepare for heel strike
Tsw - knee
extensions to neutral (5 deg flex)
extension controlled eccentrically by the hamstrings
Quads turn on in late Tsw to prepare for weight-bearing
Tsw - hip
subtle retraction to 20 deg of flx
Tsw critical event
Knee extension to neutral
What are the key muscles for pelvic control
hip ext and hip abd
Pelvic motion during gait in the sagittal plane
neutral pelvis in ~ 10 deg of anterior tilt
Slight increase in anterior pelvic tilt during Tst and Tsw
Pelvic motion during gait in frontal plane
During WA, 4 deg of contralateral pelvic drop
During Psw, 4 deg of ipsilateral pelvic drop
Pelvic motion during gait transverse plane
Max pelvic protraction (4°) during TSW and IC
Max pelvic retraction (4°) during TST
Neutral rotation at MSW and MST
Average vertical displacement
4.2 cm
Average lateral displacement
4.5 cm to the R and L
Trunk during gait
Multifidus act bilaterally during IC
Low level activity of rectus abdominis and external obliques
The arms provide counterforce to oppose
excessive rotation of the body
UE
Peak flexion (shoulder = 8°) during contralateral initial contact
Flexion is a passive movement
Peak extension (shoulder = 24°) during ipsilateral initial contact
Extension is controlled by posterior deltoid and teres major
Arm swing range (increased extension) increased with increased walking velocity
critical joint angles - ankle
neutral ankle during swing
20 deg of DF in terminal stance
critical joint angle - knee
60 deg of flexion in intial swing
20 deg of flexion in loading response
0 in at IC and midstance
critical joint angle - hip
25 deg of flx in midswing
20 deg of extension in terminal stance
Critical muscle activity - ankle
anter tib during loading response (eccentric)
anter tib during swing (concentric)
Gastrocnemius active during stance to control knee flexion movement
Critical muscle activity - knee
No hamstring or quadriceps muscle activity during Msw
Quadriceps active during stance to control knee flexion movement
Critical muscle activity - hip
hip flexors during swing (concentric)
hip abductors during single limb support to prevent hip drop
Faster walking speeds create
higher peaks and lower valleys
Increase knee adduction moments have been associated with
knee OA
Goal of gait methods
is the individual achieving a functional, comfortable, biomechanically, efficient, and energy efficient gait
Gait methods
Manual assessment of spatial and temporal parameters
Instrumented Walkways
Three-Dimensional Gait Analysis
Video Analysis
Observational Gait Analysis
Outcome measures for manual assessment of spatial and temporal parameters
6 MWT
2 MWT
10 meter walk test
Physical measurements of manual assessment of spatial and temporal parameters
step length, step width, or cadence
Advantages of instrumented walkways
Easy to use
Less expensive
Portable
Requires minimal set up
Requires minimal space
Generally produces reliable data
Limitations of instrumented walkways
Generally limited to temporal spatial data acquisition
Limited to number of steps
Artificial environment validity?
GAITRite
2 ft wide x 12-24 ft length walkway
Numerous client-specific normal databases can be created and compared against
Can use to track a patient’s progress
Which gait analysis is the gold standard
three-dimensional gait analysis
Three-dimensional gait analysis
measures temporal spatial parameters, kinematics, and kinetics
Advantages of three-dimensional gait analysis
Captures joint kinematics and kinetics in all planes
Accurate
Good for complicated gait patterns
Can sync with EMG data
Limitations of three-dimensional gait analysis
Need large room
Costly
Must have knowledge to process data
Accuracy influenced by body composition and precision of marker placement
Skin artifact
Capture rate
minimum 60 Hz for walking for faster movements must increase rate
detecting gait events
foot strikes on force plates
velocity of foot
foot switches
Can a EMG distinguish if muscle contraction is concentric, eccentric, or isometric
there is no way
EMG surface
Non-invasive
Good for group and/or surface muscle activity
Should be placed at muscle belly
Good for measuring timing of muscle activity
Signal can be “noisy”
Does not work well with thick layer of subcutaneous fat
EMG fine wire
Invasive
Good for deep or specific muscle activity
Needles must be sterilized
In CA, need to be certified to perform
Time intensive
Plantar Pressures
Instrumented insoles place in patient’s shoes
Can not use during barefoot walking
Published “normals”
Inertial measurement units
Self-contained system that measures linear and angular motion with the use of gyroscopes, magnetometers, and accelerometers
Advantages of video gait analysis
Measures joint angles
Inexpensive
Simple to use
Limitations of video gait analysis
Accuracy
Patient consent to video
Tips for observational gait analysis
Must be familiar with NORMAL gait first!
Start global then get specific
Breakdown into stance and swing and then further into phases
Can list in order of significance or superior inferior
what are the 3 main functional task of gait
weight acceptance
single limb support
swing limb advancement