Liners and Suspension
Today there are several options to hold the prosthesis on to the residual limb as opposed to the belt/cuff strap of the past. Common suspension includes liners next to the skin and either a pin and lock or a sleeve on the thigh, both of which provide additional comfort and protection for the residual limb. Various alterations and adjustments can be made to tailor each patient’s wants and needs. The following examples are just some of the newer technology available for liners and suspension.
Locking suspension: This type of suspension has a pin on the distal end of the liner that locks into the prosthesis, providing a secure connection between the patient and the prosthesis. One of the main advantages of this type of suspension is the sense of security provided to the wearer. It is a positive mechanical connection to the body without an additional sleeve.
Suction suspension: Suction suspension works by forming a seal between the residual limb and the socket. When the liner enters the prosthesis, air is forced out of a valve at the bottom of the socket. Opening the valve or removing the sleeve releases the suction and allows for removal of the prosthesis. Suction suspension improves proprioception and can make the prosthesis feel lighter by minimizing movement in the socket.
Custom Liners: Designed by a certified prosthetist to fit each amputee’s unique limb shape, a custom liner is recommended for patients with prominent bony limbs, limbs with sharp or irregular contours, a high level of sensitivity, and/or significant scarring such as skin grafts.
Össur Iceross® Seal-In® Liner: This liner is available for transtibial and transfemoral amputees. They have a variety of 1 to 5 seals that create an airtight fit as the rings seal to the socket. This seal creates a suction suspension system, minimized pistoning, and enhanced rotational control allowing users to enjoy greater comfort and stability.
Vacuum Suspension: Elevated vacuum suspension systems manage limb volume fluctuation, a challenge that people with limb loss may face. Over time and on a daily basis, these volume changes can affect how the socket fits. When the limb volume increases, the socket becomes tighter, exerting pressure, restricting blood flow, and allowing for accumulated cell waste. When limb volume decreases, the socket is loose-fitting, often causing pressure to bony prominences, which may result in pain and/or injury to the limb. One of the most important benefits of elevated vacuum suspension is that it maintains limb volume throughout the day. It also improves proprioception and gait.
Ottobock Dynamic Vacuum System (DVS): Reducing the movement between the limb and socket associated with limb volume fluctuations, the DVS pump connects to the specific DVS liner magnetically and a knee sleeve is used to seal the system. Vacuum is generated during walking and this elevated vacuum is maintained in both the swing and stance phase as opposed to passive systems, such as a one way valve that only generate suction during swing phase. This give the user enhanced control and fit during all phases.