LE Prosthetics - 2 - Assessment Flashcards
Functional testing
Prosthetist can’t do it to get reimbursed, so they have to have someone else do it
PTs!
How do we do functional testing
Amputee mobility predictor!
Amputee mobility predictor - what is it
21 tests for assessing particular level of function in a patient
made by Gailey
Amputee mobility predictor! - what does it take
Simple equipment
Stopwatch, 12 inch ruler, 4 in box, 2 chairs
Amputee mobility predictor - scoring
K levels
Amputee mobility predictor! - K0
Regardless of prosthesis you give them, they will not walk
Amputee mobility predictor - K1
transfer prosthesis
value of it - safety - could be the difference that allows them to be more independent and allow them to be home
Amputee mobility predictor! K2
Single speed ambulator
So no matter what, is always going the same speed
Can usually only traverse low level barriers in community
Amputee mobility predictor! K3
Multispeed ambulator (they can change their speed) No barriers - unlimited community ambulator
Amputee mobility predictor! K4
High activity like sports
Other than peds, most of us do not function at K4 level
Expectations
Setting expectations
Know what each participant expects - need to understand what they want to do with their prosthesis
What are they motivated to accomplish
K1 what kind of knee
Manual locking
Gives stability
K2 - what kind of knee
Manual locking
Weight activated control
Pneumatic knee systems
Polycentric4 or 7 Bar linkage systems
K3 and K4 - what kind of knee
Polycentric4 or 7 Bar linkage systems
Hydraulic control
3 views of prosthetic gait - planes
Sagittal is the most common that prosthetists talk about
Frontal would be next (looking at varus/valgus forces)
CAUSE
Component Alignment User Socket Education
CAUSE - component
any piece of the hardware that is causing the issue
CAUSE - alignment
something off with the alignment - maybe too much rotation
When they measure alignment, the manufacturer tells them where the alignment should go
CAUSE - User
maybe they have something to cause the dysfunction (maybe tight hip ER)
CAUSE - socket
if socket does not fit properly
Varicose hyperplasia - pt not making contact distally so get suction - cancer risk!
CAUSE - education
person wearing it
PT
prosthetist
The challenge - cluitmans
Any prosthesis necessitates a good suspension in swing phase and adequate pressure distribution in the stance phase
The challenge - johannesson
Amputees are exposed to a high degree of load at all times
Difference is that the structures (skin) that are exposed to the loads are not originally intended for this purpose
Diabetic skin tissue overview - Distal end blistering
usually caused by void or space in distal aspect
Diabetic skin tissue overview - Irritation following removal
mineral build up
could be related to perspiration - crystalize and cause itchiness
Intersurface selection - residual limb length - suspension option - SHORT
Upper 1/3 Locking suspension - Volume instability - Security Cushion/sleeve - Simplicity
Intersurface selection - residual limb length - suspension option - MEDIUM
middle 1/3 Locking suspension - Volume instability - Security Seal in suspension - ease of use and ROM - low build height Cushion/sleeve - Simplicity
Iceross liner selection - the issue
Poor suspension Inc shear Inc peak pressure Discomfort Tissue damage
Iceross liner selection - the soluation
Rolling it on (invert it first) Reduce pistoning Absorb shear Dissipate peak pressure Protect skin envelope Stabilize soft tissue
Shore value/Durometer is what
Measure of hardness
Iceross liner durometer/design
Dermo Comfort Synergy Sport Transfemoral Original
Iceross liner durometer/design - comfort is
30
Iceross liner durometer/design - dermo
25 (softest)
Iceross liner durometer/design - synergy
40/25
soft on inside, hard on outside
good for active person
Iceross liner durometer/design - sport
get more proprioception and feedback from it
50/25
Iceross liner durometer/design - transfemoral
High durometer
50
we have a lot of soft tissue so don’t need as much padding
Iceross liner durometer/design - original
60
Iceross liner durometer/design - indicated for diabetic amputees
Synergy (40/25)
Comfort (30)
Dermo (25)
Iceross liner selection - thickness
3 MM
6 MM
Iceross liner selection - thickness - 3 MM
Distal protection Tapered to grade pressure Thin around knee Reduced pressure on thigh Designed for protection and performance
Iceross liner selection - thickness - 6 MM
Distal protection
Enhanced proximal protection
Designed for ultimate tissue protection
Iceross liner selection - sizing technique
Measure 4cm from distal end
Measure circumference
Select Iceross as measured (if btw sizes, downsize with seal in liner)
Iceross liner selection - suspension options
Locking
Cushion (use sleeve on outside)
Seal in (leave on inside of socket)
Iceross liner selection - Suspension options: Locking
Matrix - prevents tissue stretching
Size specific umbrella to prevent compression
Overall prevents movement up and down btw the prosthesis
Socket design - total surface bearing- describe
Vlume match (residual limb to socket) Distribution of load over max area Control of soft tissue position Minimize pressure peaks Minimal movement of bone/socket Forces normal to surface (less shear) Optimized with pressure casting
Socket design - total surface bearing - axial/dynamic forces
Socket shaping
Pre-compression of soft tissue
Adaptation of liner thickness
Socket design - total surface bearing- rotational forces
Shear absorbed by the liner
Contact area with socket wall
Socket design issues
Reliefs and air pockets
Posterior wall trimmed too low
Volume related issues
Undersized (M/L instability)
Even/Correct
Oversized (fibula head and distal tibial pressure)
CadCam imaging
Computerized image of residual limb
Modifications and socket adjustments made on computer
Digital image created and stored in database
Data transferred to produce exact socket
Prosthetic feet - recommendation
prescribed according to activities the pt has the potential to achieve
Prosthetic foot serves the purose of
connecting the prosthesis to the ground
Classification of prosthetic foot - single axis
Foot with a hinge to it Allows PF and DF Rapid foot flat Provides knee stability Primarily rx for transfemoral amputees
Classification of prosthetic foot - multiple axis
Allows foot to accommodate terrain
Inv/ev
Classification of prosthetic foot - SACH
Solid ankle cushioned heel Low maitenence Low cost Adjusted heel heigh The ultimate in durabiity
Classification of prosthetic foot - Elastic keel
allows for compliance
Classification of prosthetic foot - Dynamic response
Energy storage at heel strike
Spring in heel compresses and as they come foward it will decrompress and help with push off
Energy storage in loading response
Bench alignment - sagittal plane
Sagittal plane
Socket flex 5-10 deg
Mark ntersection of post and middle third of foot
Alignment reference line should fall at junction of the posterior and middle third of the foot length
Bench alignment - coronal plane
Coronal plane
Socket add 5 degrees
Bisect socket
Static alignment
knee in neutral flex/ext
full WB
Assess coronal balance
pelvic stability
Shoes
Consider stability, safety of remaining foot, don and doff, consistent heel height, cosmesis
Make sure same heel to toe ratio for shoes worn
Dynamic alignment checklist
Height level Smooth trans to stance Swing smooth Proper heel/toe lever Proper stiffness in heel Limited shift in socket Vertical pylon Body symm Arm swing
Transfemoral levels
Knee disarticulation - adductors still intact, long residual limb BUT knee center lower than other side
Long AK - still long residual but now 70% of add gone so less stability
Short AK - still functional but see a lot of Trend
Hip disarticulation - works like bench so can still be functional (usually CA)
Hemipelvectomy (Not functional, usually CA)
Transfemoral - Preparation for fitting
Wrapping limb Distal to proximal No gaps Above the hip Requires multiple applications Shrinker socks
Socket design - transfemoral
Quad
Narrow medial lateral (ischial containment)
Socket design - transfemoral - ischial component
Comes up on medial side of ischial tub creating a bony lock
Typically less comfortable
Socket design - transfemoral - quadrilateral
they sit on ischial tub like sitting on bench
Transfemoral - Bench alignment
Socket rotation
External foot rotation
TKA - Trochanter knee ankle
Tend to have more flexion contractures
Transfemoral - Bench alignment - TKA
Trochanter knee ankle
Stationary alignment line to identify relative alignment between the center of the socket weight line, the rotation point of the knee and the functional rotation point of the ankle/foot
Transfemoral - Static alignment
Stationary alignment to establish:
- height
- foot rotation
- socket position: flexion/ext, ad/abd, AP position, ML position
Transfemoral - Dynamic alignment
Allows for minute adjustments to the prosthesis
Customizes alignment of prosthesis to the pt needs
Ensures max activity and stability resulting in achieving the highest possible outcome
Transfemoral - Alignment - purpose
The goal is to align the prosthesis so that the amputee uses the minimum amount of alignment stability or involuntary knee control necessary to optimize voluntary control
Critical balance between mobility and stability to a achieve a safe and efficient gait
