Overview of Lower Limb Prostheses

Question 1

Partial Foot:

Answer 1

Toe, ray, transmetatarsal, Lisfranc, Chopart

Often require carbon foot plates or AFO-style devices

Common to have higher level amputations within a few years

Question 2

Lisfranc

Answer 2

Disarticulation of the tarsal and metatarsal bones

Question 3

Chopart

Answer 3

Foot disarticulated between the talonavicular and calcaneocuboid joints

Question 4

Ankle Disarticulation:

Answer 4

Weight-bearing possible, leg length discrepancy common

Question 5

Transtibial (TT):

Answer 5

Most common; outcomes depend on residual limb length and socket fit

Question 6

Knee Disarticulation:

Answer 6

Long lever arm; good weight bearing but bulky

Question 7

Transfemoral (TF):

Answer 7

Stability decreases as femoral length decreases; adductors often lost

Question 8

Hip Disarticulation / Hemipelvectomy:

Answer 8

High energy demand, low symmetry, often poor cosmesis

Question 9

Socket

Answer 9

Connects limb to prosthesis; can be rigid or flexible

Question 10

Interface

Answer 10

Liner, socks, or foam for comfort and volume management

Question 11

Suspension

Answer 11

Holds prosthesis on: suction, pin-lock, belts, anatomical

Question 12

Pylon

Answer 12

Connects socket to foot/knee; often tubular aluminum/carbon

Question 13

Foot

Answer 13

SACH, single-axis, multi-axis, dynamic response, hybrid

Question 14

Knee

Answer 14

Polycentric, hydraulic, pneumatic, microprocessor

Question 15

Stages of Rehabilitation

Answer 15

pre-surgery
postoperative
preparatory
definitive

Question 16

Pre-surgery

Answer 16

Patient/caregiver education

Peer support

Strengthening upper limbs & core

Question 17

Postoperative

Answer 17

Rigid dressing and compression therapy

within 24 hours

pre-prosthetic training
temporary device
2-4 weeks

Question 18

Preparatory prosthesis

Answer 18

4 to 8 weeks

Question 19

Definitive prosthesis

Answer 19

6 to 12 months

ongoing care

Question 20

New Amputees
Challenges and Priorities

Answer 20

Regaining balance

Rebuilding proprioception

Establishing security and confidence

Establishing good walking habits

Question 21

The actual physical evaluation of ___ is a critical step in the recommendation of the prosthesis.

Answer 21

the patient and the residual limb is

Question 22

Four variables specific to the residual limb:

Answer 22

1) Condition of the residuum
- Sensation vs. Pain
- Shape
- Palpation of Bony Anatomy
- Skin Integrity & Quality

2) Stability of remaining joints
- M/L Stability
- A/P Stability

3) Muscle strength

4) Range of motion

Question 23

Socket Types
Transtibial

Answer 23

PTB (Patellar Tendon Bearing)

TSB (Total Surface Bearing)

SC-SP (Supracondylar-Suprapatellar)

Joint & Corset – for max M-L support

Question 24

Socket Types
Transfemoral

Answer 24

Ischial Containment – contains ischium for stability

Sub-ischial – lower trim lines, may use vacuum suspension

Question 25

Suspension Systems Transtibial

Answer 25

Roll-on liners with pins Suction Suspension sleeves Anatomical (SC/SP or supramalleolar) Cuff suspension or belts

Question 26

Suspension Systems Transfemoral

Answer 26

Roll-on liners (pin or suction) Skin-fit suction Belts Rigid vs. soft socket interface

Question 27

Prosthetic Foot Categories

Answer 27

SACH – Solid ankle, cushion heel (basic) Single Axis – Dorsiflexion/plantarflexion only Multi Axis – Adds inversion/eversion Dynamic Response – Energy-storing feet Hybrid Designs – Combine multiple features

Question 28

Prosthetic Knees

Answer 28

single axis polycentric hydraulic microprocessor

Question 29

Prosthetic Knees- Single Axis

Answer 29

Simple hinge, stance-lock, friction control

Question 30

Prosthetic Knees- Polycentric

Answer 30

Four-bar linkage, natural knee motion

Question 31

Prosthetic Knees- Hydraulic/Pneumatic

Answer 31

Fluid/gas resistance, adjustable swing/stance

Question 32

Prosthetic Knees- Microprocessor

Answer 32

Computer-controlled; variable cadence and terrain

Question 33

Optimal Prosthetic Gait stance

Answer 33

Equal stride length Foot flat on the floor Knee flexion in stance M-L stability at midstance

Question 34

Optimal Prosthetic Gait swing

Answer 34

Equal heel rise, hip rotation & arm swing Toe clearance Controlled deceleration

Question 35

Limited Community Ambulator

Answer 35

Low activity Low voluntary control Single speed ambulation Activities involve walking primarily indoors on level, even ground

Question 36

Limited Community Ambulator Prosthetic requirements:

Answer 36

Stability Confidence that the knee/foot will support them at all times Comfort in the socket Reliable suspension Swing toe clearance

Question 37

Community Ambulator

Answer 37

Moderate activity Moderate voluntary control Primary focus on walking activities including level, uneven ground and ramps

Question 38

Community Ambulator Prosthetic requirements:

Answer 38

Balance between performance & stability Components to allow for change in walking speed Adaptable components for change in surfaces or slopes Comfort and control of the socket Reliable suspension

Question 39

Unlimited Community Ambulator

Answer 39

Higher activity Full control of prosthetic Has the ability to quickly change speed Has higher demands and goals for prosthetic Needs a device that can keep up with activities

Question 40

Unlimited Community Ambulator Prosthetic requirements:

Answer 40

Balance Variable speed Higher impact Multifunction knee Energy return foot Biofeedback and Responsive socket deign

Question 41

k1 needs

Answer 41

Household/Level K1 Stability, comfort, support indoors only

Question 42

k2 needs

Answer 42

Limited Community (K2) Confidence, suspension, toe clearance

Question 43

k3 needs

Answer 43

Community Ambulator (K3) Variable cadence, uneven terrain

Question 44

k4

Answer 44

Unlimited Community (K4) High performance, responsive knees/feet, energy return