There are six basic prosthetic options to consider for the upper-extremity amputee and the type of prosthesis selected/suggested/recommended is based on many factors, including level of amputation, condition of residual limb, individual goals and work requirements. Often more than one option may be required for an individual to accomplish all of his or her goals.

Our philosophy is that every amputee should be exposed to the six prosthetic options available and have an opportunity to decide which option is appropriate for his or her lifestyle and needs. Personal requirements may be function-related, cosmetic or psychological in nature. Following is an overview of the six prosthetic options:

• No Prosthesis
• Cosmetic Restoration
• Body-Powered Prosthesis
• Electrically-Powered Prosthesis
• Hybrid Prosthesis
• Activity-Specific Prosthesis 

Not every person is a candidate for a prosthesis, and even if he or she is, many choose not to wear or use one. Only half of all upper-extremity amputees ever receive prosthetic services. Of those, as many as half choose not to use or wear their prosthesis one year from initially receiving it. For many amputees, their level of function is simply not enhanced by the use of a prosthesis. Also, some amputees who cannot obtain funding are provided with a prosthesis that does not address their individual needs, or had a poor first experience that may have included pain, discomfort and poor function; and thereafter, choose not to pursue further prosthetic care.

However, some upper-extremity amputees who have chosen not to wear prostheses in the past have found that the advanced fitting techniques and components now available through an experienced prosthetist, who specializes in upper-extremity prosthetics, can enhance their lives.

Cosmetic restoration, or duplication of the contralateral arm or hand, is a popular prosthetic option. This involves replacing what was lost from amputation or congenital deficiency with a prosthesis that is similar in appearance to the non-affected arm or hand and provides simple aid in balancing and carrying.

A cosmetic prosthesis is sometimes called a passive prosthesis because the prosthetic hand is non-functional and it rarely provides the ability to grasp items. Cosmetic restoration is typically achieved using one of three materials: flexible latex, rigid PVC or silicone. These types of prostheses are often lighter weight than other prosthetic options and require less maintenance because they have fewer moving parts than other prosthetic options.

Overview of Materials

• Latex Covering – Latex covering is the most common material used for cosmetic restorations. Latex is usually a thin material that comes in pre-made sizes or gloves to fit over most available prosthetic hands such as passive, body-powered or electrically-powered. A latex glove is most often provided in a solid color that can be enhanced by custom painted details such as freckles, nails, age spots and knuckles. Partial hand restorations can be made with this material and often utilize a zipper in the palmar surface to allow the patient to easily don and doff the prosthesis but still have the stability and confidence that the prosthesis is firmly attached.
  
  Latex covering is fairly lightweight and inexpensive. Unfortunately, latex stains easily. Most wearers replace a latex glove 3-12 times a year due to wear and staining and some patients say that it lacks the realism (aesthetics) offered by other materials.

• Rigid PVC – This material is most often used on individuals with amputations or deficiencies above the wrist disarticulation level. It acts as a glove and may come in a variety of colors and sizes. The gloves are solid color core and therefore retain color if scratched or stained.

• Silicone – Silicone has been around for many years, but only recently has it been refined for utilization in upper-extremity restorations. The process to receive a silicone restoration is more complex than others, due to its customized nature. However, it often provides the most realistic and long-lasting restorations. Realism is achieved by the varied texture of silicone, size and shape matching through custom molding and color duplication utilizing multiple photographs or onsite color matching of the non-affected hand.
  
  Cosmetic restoration using silicone often goes unnoticed because it so closely resembles the non-affected hand. Silicone does not stain like latex and it provides the highest cosmetic restoration quality, with longevity of three to five years.
  
  One disadvantage of silicone is that it is heavier than latex and can only be used with certain types of prosthetic hands, specifically those that utilize an endoskeletal design. Silicone is also more expensive and takes longer to fabricate.

A body-powered prosthesis, sometimes called a conventional prosthesis, is powered and controlled by gross body movements. These movements, usually of the shoulder, upper arm or chest are captured by a harness system, which is attached to a cable that is connected to a terminal device (hook or hand). For some levels of amputation or deficiency, an elbow system can be added to provide the patient additional function.

Because of its simple design, this type of prosthesis is highly durable and can be used for tasks that involve water and dust and in other potentially damaging environments. Many patients who wear a body-powered prosthesis comment that they have increased control due to a phenomenon called proprioception, which gives the wearer feedback as to the position of the terminal device. There is also a reduced maintenance cost for a body-powered prosthesis.

The most common complaint that wearers of this type of prosthesis note is the uncomfortable and restrictive control harness. Although new materials aid in reducing discomfort, the harness must be tight in order to capture the movement of the shoulder and suspend the prosthesis. The tight harness can also restrict range of motion. Other patients dislike the look of the hook and control cables and request a prosthesis that is more "lifelike."

Electrically-Powered Prosthesis

This category of prosthesis uses small electrical motors to provide function. These motors can be found in the terminal device (hand or hook), wrist and elbow. This type of prosthesis utilizes a rechargeable battery system to power the motors. Because electric motors are used to operate hand function, grip force of the hand is significantly increased, often in excess of 20-32 pounds.

There are several ways to control this type of prosthesis including Myoelectric Control, Servo Control, Linear Potentiometer, Force Sensitive Resistors (FSR), Push Button Control and Harness Switch Control. Additionally, several control schemes may be used on the same prosthesis to provide enhanced function.

Unlike the other prosthetic options, the electrically-powered prosthesis uses a battery system that requires a certain amount of maintenance which includes charging, discharging, eventual disposal and replacement. Because of the battery system and the electrical motors, the electrically-powered prosthesis tends to be heavier than other prosthetic options, although advanced suspension techniques can minimize this sensation.

When properly fit and fabricated, electrically-powered prostheses do not require a lot of maintenance. However, when repairs are required they are often more expensive than other options due to their sophistication. Additionally, an electrically-powered prosthesis is susceptible to damage when introduced to moisture.

A hybrid prosthesis combines body power and electrical power in a single prosthesis. Most commonly, hybrid prostheses are used for individuals with transhumeral (above the elbow) amputations or deficiencies.

The hybrid prosthesis often utilizes a body-powered elbow and a myoelectrically-controlled terminal device (hook or hand). If desired by the wearer, a myoelectrically-controlled wrist and a cosmetic restoration of the forearm and hand may also be included. Another type of hybrid prosthesis combines an electrically-powered elbow with a body-powered hook or hand. While shoulder disarticulation level amputations or deficiencies have been fit with hybrid prostheses, these cases should be carefully considered because of the amount of gross body movement needed to operate this type of prosthesis and the EMG signal interference created during such movement.

There are several unique advantages to a hybrid prosthesis. Most importantly is the ability to simultaneously control elbow flexion and extension while opening or closing the electric hand/hook or while rotating the wrist. The other prosthetic options generally require the wearer to control one function at a time (flex the elbow, lock the elbow, open or close the terminal device). The hybrid prosthesis weighs less and is less expensive than a similar prosthesis with an electrically-powered elbow and hand. The same disadvantages apply to the hybrid as to the prosthetic options it incorporates.

Activity-specific prosthesis is designed specifically for an activity in which the use of a passive, body-powered, electrically-powered or hybrid prosthesis would place unacceptable limitations on function or durability. Often this type of prosthesis is recreational in nature for activities such as fishing, swimming, golfing, hunting, bicycle riding and weight lifting, but prostheses have been created for such activities as music and work-related tasks.