Suction System

Suction suspension is also a common method of suspension for a transtibial prosthesis. The suction cups on your windows work in a similar way. When a suction cup is pressed against a window, the air between the window and surface of the suction cup is expelled, and a “mini vacuum” is created This “vacuum” is what holds a suction cup in place.

How It Works

A liner without a pin (cushion liner) and a knee suspension sleeve are the main components of this system. Instead of a locking mechanism incorporated into the inside of the socket, a valve or a pump is used. When the limb is pushed into the socket, air is expelled out of the pump or valve. A knee sleeve is rolled onto the thigh and seals off the system, preventing air from entering the socket and holding the prosthesis on the limb.


A one-way valve is used to expel the air out of the system. Air is allowed out of the system, but not inside the system.


A mechanical or electric pump attached to the prosthesis is used to expel or evacuate the air from the system. This is also referred to as elevated vacuum suspension (keep scrolling down)

Roll the silicone liner on the limb. Place the limb inside the socket. Roll the knee sleeve on to the thigh.

suctionsys Labeling Sleeve, Socket, Pylon, and Foot - P&O Care - Prosthetic and Orthotic Care

Elevated Vacuum Suspension

Elevated vacuum is a type of suction suspension utilizing a pump to evacuate air out of the prosthetic system (air between the prosthetic liner and the walls of the socket). Introduced in 1999, the elevated vacuum system took the passive suction technology one step further by adding a pump (as opposed to a simple one way valve) creating unparalleled suspension and security for prosthetic users. Hundreds of peer-reviewed studies have found the following benefits of elevated vacuum suspension:

– Increased “linkage” between prosthesis and patient
– Reduced daily volume fluctuation
– Reduced limb pistoning or movement within the socket
– Improved limb health


– Active Suction Socket
– Vacuum Assisted Socket

There are two basic types of elevated vacuum pumps used to push air out of a prosthetic socket, mechanical and electrical.

Electrical Pump

As the user steps down onto the prosthesis, air is pushed out of the prosthesis (and not allowed back in) creating a vacuum environment. No batteries or chords are needed and the system is very quiet.

Mechanical Pump

A battery powered pump actively sucks the air out of the socket when the vacuum level dips below a certain level. Daily charging is recommended and electrical pumps are louder than the mechanical vacuum pump when in use.

Common Questions

1. Does the vacuum touch the skin?

No! The vacuum is actually present between the liner and the sides of the socket.

2. An elevated vacuum pump adds weight to the prosthesis. Don’t you want to have the lightest prosthesis possible?

The weight of an elevated vacuum system is NOT usually perceived by the user due to the superior linkage of the prosthesis to the residual limb!

P&O Care provides Elevated Vacuum Suspension componentry from the following Manufacturers:

ossurlogo - P&O Care - Prosthetic and Orthotic Care
willowwoodlogo - P&O Care - Prosthetic and Orthotic Care
5280 puck tech logo - P&O Care - Prosthetic and Orthotic Care
ottobock_logo - P&O Care - Prosthetic and Orthotic Care

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