Skin that comes in contact with the socket of the prosthesis must be cared for and carefully checked to prevent skin breakdown and skin infection. Skin breakdown is when the skin is damaged and develops blisters or sores. Pain is the first indication of a problem. When an unpleasant sensation is first felt, the person should remove the prosthesis and inspect the skin.
Skin problems can be serious and should be evaluated and treated as necessary by a health care practitioner in consultation with the prosthetist (an expert who designs, fits, builds, and adjusts prostheses). As people become familiar with recurrent problems, they may be able to identify which problems are minor and manage them on their own. However, anything unusual, persistent, painful, or worrisome should be evaluated by a health care practitioner.
(See also Overview of Limb Prosthetics.)
Disorders that decrease circulation to the lower limbs (such as blood vessel disorders or diabetes) and put people at risk of amputation also increase the risk of skin breakdown and infection after amputation.
Some of these disorders (such as diabetes) and others (such as neurologic disorders) impair the ability to feel pain and other sensations. People with such disorders may not feel discomfort or pain when skin breaks down or infection develops and thus do not notice these problems. These people should remove their prosthesis several times a day to check the skin for redness and other signs of breakdown or infection. Other people should check for these signs at least once daily.
Skin problems are more likely when the residual limb has certain features, including too much tissue at the end of the bone, loose skin, burned skin, skin grafts, thick or deep scars, and bumps or sharp points on the end of the bone.
If the prosthetic socket fits optimally, skin problems are minimal. But even with good fit, normal limb changes such as muscle shrinkage and day to day differences in fluid volume can alter the stump-to-socket relationship and increase risk of problems. If the upper portion of the socket is too tight, circulation is impeded and the limb can swell, which increases pressure over the distal residual limb and risks skin deeper tissue problems. If the socket is too loose, excess pressure will be applied to the end of the limb and bony prominences causing skin problems.
Skin breakdown usually occurs where there is pressure and/or friction on the skin, especially when the pressure is applied upward and downward or sideways across the surface of the skin. Risk is greater when the skin is wet or moist (such as from sweating).
The first sign of skin breakdown is redness and a burning sensation, which may be followed by pain, swelling, blisters, and ulcers. Continuing to wear the prosthesis causes more serious skin damage and can lead to skin infection.
Although it is not possible to prevent all skin breakdown, several measures can help prevent or delay skin breakdown:
Practicing good stump hygiene: Good hygiene includes washing the residual limb with a mild soap and rinsing thoroughly 2 times a day (more often for people who sweat more than normal); the prosthetist can provide antiperspirant products specifically designed for people with prosthetic devices
Maintaining interface and socket fit
Maintaining a stable body weight: This is the best way to make sure the prosthesis continues to fit; even small changes in weight can affect the fit
Eating a healthy diet and drinking water throughout the day: This helps control body weight and maintain healthy skin.
Monitoring and controlling blood sugar (for people with diabetes)
Ensuring that the prosthesis is aligned optimally (for people with a lower-limb prosthesis)
When people detect signs of skin breakdown, they should promptly see their prosthetist and, if necessary, have the prosthesis adjusted. When possible, people should avoid wearing the prosthesis until it can be adjusted. If the prosthesis is not the cause, or if fitting adjustments do not correct the problem, a doctor needs to do a medical evaluation.
In normal, dry, intact skin, bacteria and fungi are kept in balance. However, the interface (some form of a gel layer or plastic) that is against the residual limb's skin creates a warm, moist environment that encourages growth of bacteria and fungi and development of infection. Damp skin also tends to breakdown, giving bacteria easy entry into the body. As a result, infection may spread.
Signs of infection include tenderness, redness, ulcers, and a pus discharge. A bad odor may indicate infection or poor hygiene. If a minor bacterial infection progresses to cellulitis or produces an abscess, the person may have fever and not feel well.
Any sign of infection needs to be evaluated by a doctor. The following symptoms require immediate evaluation to prevent infection from becoming life threatening:
The residual limb feels cold (indicating decreased circulation).
The affected area is red and tender.
The affected area gives off a bad odor.
Lymph nodes in the groin or armpits swell.
Pus or a thick discharge is present.
The skin becomes gray and soft or black (either may indicate gangrene).
Treatment of bacterial infection typically involves local cleaning and topical antibiotics. Sometimes dead skin removal, oral antibiotics, or both are needed. Typically, the prosthesis should not be worn until the skin infection is resolved.
Fungal infections should be treated with an over-the-counter antifungal cream.
Measures to prevent skin breakdown also help prevent infections.
Ingrown hairs and infection of the hair follicle (folliculitis), although not dangerous, can cause pain or discomfort. Not shaving the hair on the residual limb can help prevent these problems.
The appearance of rough, warty bumps, usually at the far end of the residual limb, usually is the result of an ill-fitting socket. If untreated, this disorder, called verrucous hyperplasia, can lead to a serious infection. If bumps resembling warts appear, people should immediately see their prosthetist for a prosthesis socket adjustment. If this does not correct the problem in 2 to 4 weeks, people should see their doctor. Removing the prosthesis for a week and adjusting the socket fit typically correct the problem within 2 to 4 weeks.