The lack of perfect adherence of the socket to the residual limb may result in the phenomenon commonly known as “pistoning” (axial movement between the residual limb and the prosthetic socket), which may lead to a series of unpleasant issues for our patients, such as poor proprioception, inadequate control of the prosthesis, falls and serious skin issues.

The elevated vacuum generated by the use of a pump like ALPS VIP™ ensures that the socket fits perfectly and that weight is distributed evenly over the surface of the residual limb, significantly reducing some of the most troublesome problems that can arise when contact between the socket and the residual limb is compromised.

Let’s take a closer look at what elevated vacuum is and how ALPS  VIP™ ensures patients’ maximum comfort when wearing the prosthesis.

Elevated vacuum suspension is a system where a mechanism or pump pulls the air out of the prosthetic socket, generating a negative pressure that is the same across the whole surface; this negative pressure pulls the liner and the patient’s residual limb toward the inner socket wall. It is called “elevated” to distinguish it from a simple one-way expulsion valve; this latter is able to reach a minimal level of vacuum (0 to 2 mmHg of pressure), while the elevated vacuum generates a higher pressure, that tightly secures the residual limb and the prosthetic liner inside the socket.

Benefits of ALPS VIP for lower limb amputees

• First of all, according to a variety of research studies, Elevated Vacuum Systems like ALPS VIP™ air-expulsion integrated pumps preserve residual limb skin health by improving circulation and consequently increasing residual limb oxygenation and by maintaining an effective skin barrier (as measured by Trans Epidermic Water Loss).
• ALPS  VIP™ also efficiently deals with the problem of stump volume fluctuations, improving prosthesis control. Changes in residual limb volume present serious challenges for people who use prosthetic limbs. Residual limb volume changes can, in fact, cause changes in how the prosthesis fits, creating discomfort, diminished control of the artificial limb, and increased pressure at the socket interface. Elevated vacuum systems help limit residual limb volume changes throughout the course of the day, maintaining a more steady stump volume.
• In addition, Elevated Vacuum Systems minimize pistoning, leading to better proprioception and socket stability. Reducing axial limb-socket movement also helps keep the residual limb's skin healthy and helps keep the limb in position even during unloaded conditions.
• Finally, the use of the VIP™ reduces the intensity of peaks of pressure on the patient’s limbs, improving comfort and providing greater freedom of movement for the patient