Socket Interface

Prosthetic Socks

The most valuable tool that patients have to adjust the fit of a prosthetic device are prosthetic socks. Most prosthetic devices are fabricated to a set size, but a patient’s limb is constantly changing due to weight change, activity, or maturing of their limb.

To adjust to these changes patients are supplied with a variety of prosthetic socks. The most common size’s are one ply, three ply (the same thickness as three one plys), and five ply (the same thickness as five one plys). Special size’s can also be ordered.

Prosthetic socks may be worn individually or may be worn in multiple layers, to obtain the best fit. The most common mistake is to over sock (adding to many socks at once). As a general rule only add one ply at a time to adjust to any change’s, if wearing a three ply add a one ply over the three ply to make the change to a total to four plys.

If more thickness is still needed remove the one ply and the three ply and apply a five ply, this will increase the amount of sock ply but reduce the number of socks. A guide line for below knee amputees when to add sock ply is; when mtp bar pressure starts pushing underneath kneecap and distal (bottom) pressure increase’s.

A guideline for above knee amputees when to add sock ply is; when socket brim begins to cause pressure in groin area and distal (bottom) pressure increase’s.


One of the most diverse components in design and construction available to the amputee is the gel-liner. A gel-liner is the soft interface commonly used between the residual limb and the prosthesis. Fabricated from a variety of different materials such as urethane, silicone, or thermoplastic elastomers, a gel liner helps cushion the residual limb.

To help protect the skin and reduce irratation, several manufacturers have added aloe vera, mineral oil, vaseline, and vitamin E into their prosthetic liners. The most important aspect of a gel-liner to the wearer, is the proper donning of the liner.

To properly don a gel liner, first roll the liner inside out. Next place the liner cupped to the distal (end) of the residual limb, then gently roll the liner into place.

Do not try to pull on the liner as this may cause excessive tension on the skin and soft tissue, resulting in an uncomfortable fit. Then add any socks if needed over the gel-liner for a proper fit.