Skin Care of the Residual Limb
(See also Overview of Limb Prosthetics.)
Skin that comes in contact with the prosthesis must be cared for meticulously to prevent skin damage such as irritation, skin breakdown (which may result in sores), and infection.
Usually, the disorders that put patients at risk of amputation such as blood vessel disorders and diabetes, which decrease circulation to the lower extremities, also increase the risk of skin breakdown and infection after amputation. Some of these disorders (eg, diabetes) and others (eg, neurologic disorders) impair sensation, so that patients may not feel discomfort or pain when skin breaks down or infection develops and thus do not notice these problems. These patients should remove their prosthesis several times a day to check the skin for redness and other signs of breakdown or infection. Other patients should check for these signs at least once daily.
Skin problems can be serious and should be evaluated and treated as necessary by the patient’s health care practitioner in consultation with a prosthetist. As patients 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 the practitioner.
The skin next to the prosthesis tends to break down because the prosthesis puts pressure on and rubs against it and because moisture collects in the space between the residual limb and prosthetic socket. The first sign of skin breakdown is erythema, which may be followed by cuts, blisters, and ulcers. When skin breaks down, the prosthesis is often painful or impossible to wear for long periods of time, and infection can develop. Unrecognized or unchecked infection can lead to the need for a second operation (revision surgery).
Several measures can help prevent or delay skin breakdown:
Having an interface that fits well is important. But even with a good fit, problems can occur. The residual limb changes in shape and size throughout the day, depending on activity level, diet, and the weather. Thus, there are times when the interface fits well and times when it fits less well. In response, patients can improve the fit by changing to a thicker or thinner liner or sock, by using a liner and a sock, or by adding or removing thin-ply socks. But even so, the change in the residual limb's size may vary too much and too often, making skin breakdown inevitable. Then, patients should see a prosthetist to have the interface adjusted without delay. Skin breakdown is often the first sign that the prosthesis needs adjustment.
Maintaining a stable body weight 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 lots of water help control body weight and maintain healthy skin.
For patients with diabetes, monitoring and controlling blood sugar is important.
For patients with a lower-limb prosthesis, avoiding changes in body alignment (the way they hold their body) can help. Such changes can cause skin breakdown because pressure is placed in different areas. Wearing different shoes can change alignment. For example, the heels may be a different height or have a different composition (hard rather than soft). When the prosthesis is fitted, patients can help minimize potential changes in body alignment by wearing shoes that are similar to ones they usually wear.
When patients see signs of skin breakdown, they should promptly see their practitioner to be evaluated and their prosthetist to have the prosthesis adjusted. Patients should avoid wearing the prosthesis when possible until it can be adjusted.
The socket of the prosthesis creates an airtight, warm, damp, contained space where body oils and sweat collect—an environment that encourages growth of bacteria and development of infection. Damp skin tends to break down, giving bacteria easy entry into the body. As a result, infections may spread.
Signs of infection include tenderness, skin erythema, pustules, ulcers or necrotic areas, and purulent discharge. A bad odor may indicate infection or poor hygiene. Minor bacterial infection may progress to cellulitis or produce an abscess; in such cases, patients may have fever and general malaise.
Any sign of infection should be evaluated promptly. Patients should be advised to seek immediate evaluation for the following symptoms:
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 proximal to the residual limb enlarge.
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 debridement, oral antibiotics, or both are needed. Typically, the prosthesis should not be worn until the skin infection is resolved. Erythema can indicate serious medical issues, which must be diagnosed and treated by a physician.
Patients should be taught how to help prevent infections. They should wash the residual limb with unscented, uncolored antibacterial soap at least once a day. Patients who sweat a lot or who are prone to rashes or infections should wash more frequently. An antiperspirant spray can be used, but it should have no scent or other additives; OTC sprays with < 15% aluminum chloride and stronger prescription antiperspirant sprays are available.
The prosthetist will recommend a lubricant or lotion that is compatible with the socket interface material. Some modern materials used in socket interface design can be damaged by long-term application of skin lotions, so it is best to follow the prosthetist’s or material manufacturer’s recommendation.
Any part of the interface that touches the skin—socket, prosthetic sock, or liner (see Washing the Liner)—should be washed thoroughly every day with hot water and antibacterial soap.
Liners and prosthetic socks should be dried thoroughly before wearing. Soap left in the socket or liner can cause rashes, so patients should make sure that the socket and liners are completely free of soap after washing. An itchy rash usually indicates irritation or an allergic reaction, not infection. A physician can prescribe a cream or ointment to treat rashes.
If patients can identify a fungal infection, they should apply an OTC antifungal cream. However, if the diagnosis is not clear or if a fungal infection persists, they should consult their physician.
Ingrown hairs and folliculitis, although not dangerous, can cause substantial pain and discomfort. Not shaving the hair on the residual limb can help prevent these problems.
Verrucous hyperplasia (rough, warty bumps), usually at the distal end of the residual limb, can result from an ill-fitting interface. This condition rarely occurs because of improvements in prosthetic design and fitting techniques. If untreated, this disorder can lead to serious infection. If bumps resembling warts appear, patients should immediately consult the prosthetist to check the fit and adjust the interface as needed. Then the physician should treat the verrucous hyperplasia.