There are many aspects which vary from liner to liner. Among them are thickness, flow, durometer, durability, surface tackiness, and how hygienic the material is.

The first issue is custom or not custom. The elevated vacuum socket, which is total contact and which applies a negative pressure of up to 29”Hg, will can cause serious damage to the residual limb if the liner is not total contact with evenly distributed pressures on the skin when applied. (Uneven liner pressures translate to uneven negative pressures when the vacuum is applied). The only way a precise fit can be assured is with a custom liner. 

For transtibial residual limbs with bony prominences and minimal soft tissue protection, I prefer a liner with optimal “flow” to minimize shear forces. I have used the custom TEC liner. The original TEC liner is no longer available. Otto Bock has re-named it the PUR liner and changed the formula. Otto Bock reports that it is more durable and has better flow than the original. They have tested it and gotten good feedback.

For transfemoral residual limbs that are well protected in soft tissue and don’t need the extra flow of the liner material, I prefer the platinum cure silicon liner. It is durable and hygienic and can be fabricated in our facility, giving us optimal control of the fit and the process.  

Naturally there are exceptions. I am currently fitting a bilateral transfemoral amputee who has adhesions, scarring, and prominent bone spurs. I am using bilateral custom PUR liners in this case. I am also sure that in some cases one can find and fit off-the-shelf gel liners that fit like a custom liner and are acceptable. It depends on the shape of the residual limb and the available contours of the particular liner selected. It is certainly a more convenient and cheaper option when it works out.

I am not intentionally endorsing any specific manufacturers but rather stressing the need for an accurate fit and the desired characteristics.