Q1: TT Suspension Methods Flashcards
Anatomical Suspension Methods
- joints and corset
- waist belt and fork strap
- supracondylar
- supracondylar cuff
Mechanical Suspension Methods
- knee sleeve
- locking liner
Atmospheric Suspension Methods
- passive suction
- active vacuum
Joints and Corset
- 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
Joint and Corset advantages
- very durable
- user adjustable
- ML stability
- Axial loading through thig lacer partially off-loads RL
- Hyperextension stop
Joint and Corset Disadvantages
- Heavy
- bulky
- loud
- pistoning
Joint and Corset Indications
- ML instability
- Heavy duty used
- long term satisfaction
Waist Belt and Fork Strap
- belt is attached around waist, the base for this suspension method
- elastic webbing allows comfortable knee range of motion
Waist belt and fork strap advantages
- user adjustable
- sensory feedback
- easy to visually verify
Waist belt and fork strap disadvantages
- bulky
- pistoning
Waist belt and fork strap indications
- early fittings
- auxiliary suspension
supracondyalr advantages
- self-suspending
- low profile
- provides increased ML stability
supracondylar indications
- ML instability
supracondylar contraindications
- excessive soft tissue or firm muscle proximal to condyles
- high activity
Supracondylar w/ removable brim indication
Ml-PML > 25 mm
Supracondylar Cuff
- wrap around the distal thigh proximal to femoral condyle
- suspension occurs over the patella
Supracondylar Cuff advantages
- user adjustable
- sensory feedback
- low cost
Supracondylar Cuff indications
- PTB socket design, patient has good ML stablitiy
Knee Sleeve
- mechanism is friction
- sleeve adheres to outer surface of patient’s thigh proximally
Knee sleeve disadvantages
- traps heat
- added bulk around knee
knee sleeve contraindictions
poor hand dexterity
Locking Liner
- gel liner with pin attachment adheres to residual limb
- pin attachment engages into mechanical lock in distal end of socket
Locking Liner Advantages
- audible click to confirm suspension
- quick and easy donning
- accommodats volume change readily
Locking Liner Disadvantages
- pistoning
- maintenance
Suction Advantages
- reduced pistoning
- potential for reduced in-socket rotation
Suction Disadvantages
- chance of material failure
- bulk
- heat
Suction contraindications
expected volume changes
Active Vacuum
- use of liner
- sealed system
- inner or outer seal
Active Vacuum Advantages
- minimizes pistoning
- minimizes rotation
- reduces normal daily volume fluctuations
Active Vacuum Disadvantages
- counter intuitive for prosthetists
- maintenance
Active Vacuum Contraindications
- lack of user cognition or acceptance of system
- gross volume fluctions
osseointegration advantages
- eliminates need for traditional socket
- ease of donning
