Q1: TT Suspension Methods

Question 1

Anatomical Suspension Methods

Answer 1

• joints and corset
• waist belt and fork strap
• supracondylar
• supracondylar cuff

Question 2

Mechanical Suspension Methods

Answer 2

• knee sleeve
• locking liner

Question 3

Atmospheric Suspension Methods

Answer 3

• passive suction
• active vacuum

Question 4

Joints and Corset

Answer 4

• Mechanical joints are attached to proximal aspect of socket
• joint uprights are contoured to patient thigh
• thigher lacer, or corset, is attached to joint uprights

Question 5

Joint and Corset advantages

Answer 5

• very durable
• user adjustable
• ML stability
• Axial loading through thig lacer partially off-loads RL
• Hyperextension stop

Question 6

Joint and Corset Disadvantages

Answer 6

• Heavy
• bulky
• loud
• pistoning

Question 7

Joint and Corset Indications

Answer 7

• ML instability
• Heavy duty used
• long term satisfaction

Question 8

Waist Belt and Fork Strap

Answer 8

• belt is attached around waist, the base for this suspension method
• elastic webbing allows comfortable knee range of motion

Question 9

Waist belt and fork strap advantages

Answer 9

• user adjustable
• sensory feedback
• easy to visually verify

Question 10

Waist belt and fork strap disadvantages

Answer 10

• bulky
• pistoning

Question 11

Waist belt and fork strap indications

Answer 11

• early fittings
• auxiliary suspension

Question 12

supracondyalr advantages

Answer 12

• self-suspending
• low profile
• provides increased ML stability

Question 13

supracondylar indications

Answer 13

• ML instability

Question 14

supracondylar contraindications

Answer 14

• excessive soft tissue or firm muscle proximal to condyles
• high activity

Question 15

Supracondylar w/ removable brim indication

Answer 15

Ml-PML > 25 mm

Question 16

Supracondylar Cuff

Answer 16

• wrap around the distal thigh proximal to femoral condyle
• suspension occurs over the patella

Question 17

Supracondylar Cuff advantages

Answer 17

• user adjustable
• sensory feedback
• low cost

Question 18

Supracondylar Cuff indications

Answer 18

• PTB socket design, patient has good ML stablitiy

Question 19

Knee Sleeve

Answer 19

• mechanism is friction
• sleeve adheres to outer surface of patient’s thigh proximally

Question 20

Knee sleeve disadvantages

Answer 20

• traps heat
• added bulk around knee

Question 21

knee sleeve contraindictions

Answer 21

poor hand dexterity

Question 22

Locking Liner

Answer 22

• gel liner with pin attachment adheres to residual limb
• pin attachment engages into mechanical lock in distal end of socket

Question 23

Locking Liner Advantages

Answer 23

• audible click to confirm suspension
• quick and easy donning
• accommodats volume change readily

Question 24

Locking Liner Disadvantages

Answer 24

• pistoning
• maintenance

Question 25

Suction Advantages

Answer 25

• reduced pistoning
• potential for reduced in-socket rotation

Question 26

Suction Disadvantages

Answer 26

• chance of material failure
• bulk
• heat

Question 27

Suction contraindications

Answer 27

expected volume changes

Question 28

Active Vacuum

Answer 28

• use of liner
• sealed system
• inner or outer seal

Question 29

Active Vacuum Advantages

Answer 29

• minimizes pistoning
• minimizes rotation
• reduces normal daily volume fluctuations

Question 30

Active Vacuum Disadvantages

Answer 30

• counter intuitive for prosthetists
• maintenance

Question 31

Active Vacuum Contraindications

Answer 31

• lack of user cognition or acceptance of system
• gross volume fluctions

Question 32

osseointegration advantages

Answer 32

• eliminates need for traditional socket
• ease of donning