Prosthetics-P101
Prosthetic Objectives
• Amputee perspective Prosthetic process
– Existing amputee v. New amputee
• Component selection criteria
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Suspension
Materials
Alignment
Pr(x) Feet
Pr(x) Knees
Amputee perspective Prosthetic process
• Existing Amputee
• New Amputee
– Ill fitting
– Repair cost will
outweigh new
socket/prosthesis
– Begin Prosthetic
process
Soft Removable
Dressing
– Order/Call to see new
amputee for a
protective dressing,
shrinker and or
consultation
– F/u patient to
Surgeon removal of
sutures/staples
– Begin Prosthetic
process
Amputee perspective Prosthetic process
(cont’d)
• Amputee
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–
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Begin Prosthetic process
Begin Therapy process
Initial Evaluation
Functional Testing
AmpnoPro & AmpPro
– PM&R Pre-prosthetic
Evaluation
– Component Selection
Lower Extremity Prosthetic Evaluation
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Name, age, Hgt, Wgt, Sex
Amputation Level, side
Other amputations
Ortho, neuro copathologies
Existing User
Living Status
Living Environment
– Uneven terrain, carpet,
hard surfaces
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Health comorbidities
Medications/Treatments
Ambulatory Aids
Vocational Needs
Pre-amputation activities
Patient Feedback of
current device
• Upper Extremity ROM,
MMT, dexterity
Lower Extremity Prosthetic Evaluation
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Residual Limb Features
Amputation Level
Skin health
Boney, invaginated
areas
• ROM, MMT
• Contractures
• Functional Testing
– AmpnoPro/AmpPro
• Limb Length
• Contralateral limb
Features
• Diabetic
• Callused
• Wounds
• Toe, Foot, T.T, T.F, HD
Lower Extremity Functional Testing
Outcome Measures in Lower Limb Prosthetics
K-Levels
K-Levels: K-levels are defined by Medicare based on an individual's
ability or potential to ambulate and navigate their environment.
Once it is determined in which K-level an individual resides, it can
be determined which prosthetic components are covered by
Medicare.
Bilaterals
Gait characteristics of persons with bilateral transtibial
amputations, Po-Fu Su, MS Steven A. Gard, PhD, Robert
Lipschutz, CP, Todd A Kuiken, MD, PhD
AmpNoPro
AmpPro
K-level
Description
Foot/Ankle Assemblies
Knee Units
0-8
n/a
K0
Patient does NOT have the ability or potential to ambulate or transfer
w/o assistance & prosthesis does not enhance their quality of life or
mobility
Not Eligible
Not Eligible
9-20
15-26
K1
Has the ability or potential to use a prosthesis for transfers or
ambulation on level surfaces at fixed cadence. Typical of the limited
and unlimited household ambulatory.
External keel, SACH feet or single
axis/feet
Single-axis, constant friction
knee
21-28
27-36
K2
Has the ability or potential for ambulation with the ability to traverse
low level environmental barriers such as curbs, stairs or uneven
surfaces. Typical of the limited community ambulator.
Flexible-keel feet & multi-axial
ankle/foot
Polycentric, constant friction
knee
29-36
37-42
K3
Has the ability or potential for ambulation with variable cadence.
Flex foot, and flex-walk systems, energy Fluid & Pneumatic Control knee
Typical of the community ambulator who has the ability to transverse storing feet, multi-axial ankle/feet, or
most environmental barriers and may have vocational, therapeutic or
dynamic response feet
exercise activity that demands prosthetic utilization beyond simple
locomotion.
37-43
43-47
K4
Has the ability or potential for prosthetic ambulation that exceeds the
basic ambulation skills, exhibiting high impact, stress, or energy levels,
typical of the prosthetic demands of the child, active adult, or athlete
Any ankle foot system appropriate
Any knee system appropriate
Examples
BK Socket/Suspension selection
• Socket Style
– Patella Tendon
Bearing(PTB)
– Total Surface
Bearing(TSB)
• Suspension
• Liners/Sleeves
• Research
– Öderberg, JPO 2003
PTB Socket
Style
TSB Socket
Style
Suspension/Liner Selection
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Cushion
Locking
Distal Locking
Suction
Fitting process
1. Check Socket
2. Temporary Socket
1. Check
3. Definitive
2. Temporary
3. Definitive
Foot Selection Criteria
Foot/Ankle Assemblies
K0
Not eligible for prosthesis
K1
External keel, SACH feet
or single axis ankle/feet
K2
Flexible-keel feet and
multi-axial ankle/feet
K3
Flex foot and flex-walk
systems, energy storing
feet, multi-axial
ankle/feet, or dynamic
response feet
K4
**Any ankle foot system
appropriate
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Patient Wgt.
Activity Level
Carrying Loads
Foot size
Foot Build Hgt.
Effect of wrong category of feet
• Premature failure
• Delayed/Absent Energy
Return
• Bumpers require more
maintenance
• Gait Deviations
• Skin Breakdown
The AmputeeOT
K1-Level Foot Selection
• K1-ability or potential to use a prosthesis for transfers
or ambulation on level surfaces at fixed cadence
K2-Level Foot Selection
• K2-Flexible-keel feet
and multi-axial
ankle/feet
K3-Level Foot Selection
• K3-energy storing feet,
multi-axial ankle/feet, or
dynamic response feet
K4-Level Foot Selection
• K4-exceeds basic
ambulation skills,
exhibiting high impact,
stress, or energy levels
Alignment
• Bench/Static/Dynamic
• Proper Standing
Balance
• Easier use of foot
functions
• Increased socket
comfort
• Increase Energy return
Efficacy of D.R.F
AK Socket Selection
• Socket Design
– Quadrilateral
– Ischial/ Ramal
containment
• More Anatomical
Ischial
Containment
Quadrilateral
Prosthetic Knee Selection
• Manual Locking (K1)
• Polycentric (K2)
• Weight Activated
Stance Control (K1-K2)
• Single Axis Constant
Friction
• Outside Hinges
K1 Single AxisLocking
Polycentric Knee
Knee Features
• Locking Mechanism
• Wgt. Activated Stance
Control
• Geometric Lock
• Stance Phase Flexion
• Stumble
Recovery=Stance Phase
Control
• Stance Extension Assist
• Stance Flexion Resist
• Microprocessor Control
– C-Leg, Rheo, Plie, Orion
References
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5.
https://med.noridianmedicare.com/web/jddme/education/eventmaterials/op-claim-qa
Po-Fu Su, MS, Gard, S., PhD, Lipschutz, R., CP, Kuiken T., MD, PhD, 2007.
Gait characteristics of persons with bilateral transtibial amputations.
JRRD Vol 44 Num 4, 491-502
Öderberg, B., 2003. Roentgen Stereophotogrammetric Analysis of
Motion between Bone and the Socket in a Transtibial Amputation
Prosthesis: A Case Study. JPO Vol 15 Num 3, 95-101
Atlas of Limb Prosthetics
Sinitski, E.H., et al., 2011. Biomechanics of the ankle-foot system during
stair ambulation: Implications for design of advances ankle-foot
prosthesis. Journal of Biomechanics
DOI:10.1016/j.jbiomech.2011.11.007