A Prosthetic Guide to Comfort and Stability

Making the Right Decision
A prosthesis, whether it is transtibial (below the knee), transfemoral (above the knee) or upper extremity, must have the proper components to accommodate your needs or lifestyle. Many different and technologically advanced components are available today. However, components can not provide enhanced function if they are not matched properly for your type of amputation or current level of function. Technologically advanced components will not function as intended, if you do not have the proper fit or alignment. If you already have had a prosthesis or you are being fit for the first time, it is essential that you receive a thorough evaluation. This provides essential information on your residual muscle strength, length of residual limb (critical for choosing compatible componentry), and all other details that help make a proper choice for you.

What to look for in a Prosthesis
When doing research on getting a new prosthesis, you may find that it is difficult on determining why there are differences in price. If you look at a finished prosthesis closely, you might not be able to tell why one is more expensive. But if you knew what was incorporated into each, and what function it provided you, you might conclude that quality and added function might provide you with a better and happier lifestyle. This is value. Most people will invest a lot of time and research before buying a new automobile, as they want what will suit them best. However many people forget that their most important form of transportation is walking!

Your prosthesis must be comfortable or else wearing it will be a burden, or you might not wear it at all. Comfort comes from: 1) a proper mold 2) mold modifications (measured and anatomical design of your plaster mold) 3) proper socket fabrication (the socket is what the stump/residual limb fits into), which is the final step of producing the socket from the final corrected mold. The primary reasons for an uncomfortable socket fit are: a mold incorrectly taken, incorrectly modified, or a combination of both. Medio-lateral stability (side to side stability) is extremely important in all socket fits. Without that stability you will have a residual limb that moves from side to side in the socket, causing discomfort and undermining function. In a lower extremity prosthesis, this will adversely affect alignment of the prosthesis, thereby resulting in a loss of stability.

There are many different types of suspension designs. Suspension is what holds the prosthesis onto the residual limb/stump (residual limb is the modern term for stump, however many patients still refer to their amputation as their stump). We specialize in locking-silicone suction suspension. Our patients have had wonderful success with it, both with lower and upper extremity amputations. It provides great comfort, excellent locking suspension, and a great degree of stability. However, the mold must be casted and modified correctly, otherwise the results can be compromised. Whether for below the knee, above the knee, or the upper extremity, locking-silicone liners provide a very high degree of comfort, stability, and safety. The locking-silicone suction liner is a component made of materials such as silicone, thermoplastic elastomers, or urethane. They need to be chosen carefully and properly for your needs and for your skin.

Alignment and Gait
A prosthesis must be correctly aligned to produce a natural looking or what we like to call a cosmetic gait. We have had patients come to us with existing artificial limbs, and sometimes they are very concerned about other people noticing that they wear a prosthesis.

Many times we have heard the complaint, "I wish the leg looked more real, because sometimes people stare at me when I come walking down the street". Most of the time it is not really what the prosthesis looks like that is noticeable, but an "uncosmetic gait" that attracts attention to how one is walking. Uncosmetic gait can be due to improper alignment. Alignment is the proper angular relationship between the stump, socket , artificial foot, and for the above knee amputee of most importance is the alignment of the prosthetic knee. Prosthetic components must be precisely aligned. Proper alignment increases stability, comfort, function and endurance. For new wearers, a prosthesis may be properly aligned at the time they receive the device, but increased skill in walking and balance, routinely require alignment changes to accommodate the improved function.

Therefore, it is very important to have a prosthesis that allows these alignment changes, to maximize your function and stability, which will produce a more natural and cosmetic gait.

Materials - What is the Prosthesis made of?
If you look at two different finished artificial limbs, can you tell what materials went into their fabrication? In particular the materials of the prosthetic socket?

Just by looking it is impossible to tell, especially if the socket has a cosmetic finish with a pigment . One of the most advanced materials in socket fabrication today is carbon graphite. But all carbon graphites are not alike. Some are strictly unidirectional. Some are not high modulus graphite. These are the least expensive. We only use high modulus multi-directional carbon graphite, which is the strongest and best quality graphite.

Graphite sockets: The idea of making a carbon graphite socket is to provide the patient with a socket that is light in weight, thin in design, extremely strong and durable. Sockets made with inferior graphite and resin are not as strong or durable. Unfortunately we have seen too many new patients come in with graphite sockets that were too flexible where it needed to be rigid in its structure, and the socket cracked.

When the artificial limb is completed, after you have gone through trial fittings and final alignment, and final fit, the cosmetic stage will begin. Not all patients want a cosmetic finish. Some prefer a technological type look, where all the componentry is exposed. Other factors might be that they participate in sports and want the prosthesis to be as light in weight as possible. But many people do want a cosmetic finish. There are many different types of finishes to complete a prosthesis. One of the more popular finishes is to apply a rubberized skin over the shaped prosthesis. The color is carefully matched to the patients own preference. Cosmetics are very personal, and something the patient can decide upon after discussing all of the different options.

ORTHO REHAB DESIGNS warrants its custom-made lower limb prosthetics and orthotics to be free of material defects for a period of 1 year from the date of final delivery. Ortho Rehab Designs will repair or replace, at our discretion, any device whose structure is defective without cost within the warranty period. Components are subject to the warranty provided by the manufacturer of that component.

"Each brace is custom designed for the wearer’s unique needs…no two braces are made the same."

Ortho Rehab Designs
2578 Belcastro St.
Suite #101
Las Vegas, Nevada 89117

Tel: 702.388.9909
Toll Free: 888.696.9909
Fax: 702-388-9929