Overview, Causes, & Risk Factors
A diabetic foot ulcer is an open sore or wound on the foot of a person with
diabetes. Because of loss of pain sensation, it is usually not
painful.
What is going on in the body?
A person with diabetes often has peripheral
vascular disease, or decreased circulation to the legs and feet. Any
damage to the feet may heal slowly because of the poor circulation. The person
may also have diabetic neuropathy,
a
condition in which nerve damage from diabetes causes decreased sensation in the
legs and feet. The person can develop an open area from pressure or from a cut
and not even feel the sore. Untreated, the damaged area can develop a diabetic
foot ulcer.
What are the causes and risks of the condition?
A diabetic foot ulcer is caused by direct damage to the skin, such as a cut, or
by pressure, such as that from poorly fitting shoes. The following factors increase a
person's chance of developing a foot ulcer:
diabetic neuropathy, with
damage
to the nerves supplying the feet
peripheral vascular disease,
with
decreased blood flow to the feet
a history of 10 years or more of
diabetes
smoking
male gender
blood sugar levels that are
not
under control
diabetic retinopathy, or damage to
the retina of the eye from diabetes
cardiovascular problems caused by
diabetes
kidney problems caused by diabetes, including chronic renal failure
a history of skin ulcers or
amputation of
a limb
conditions caused by increased pressure on the feet, such as corns and
calluses
foot bones that are deformed or have limited movement, such as bunions
thick toenails
Symptoms & Signs
What are the signs and symptoms of the condition?
Early symptoms of a diabetic foot ulcer include redness of the skin,
blistering, and other signs of irritation. In later stages, the person may have
an open wound that drains fluid onto socks or bedding. The open wound can then
become infected and develop swelling, redness, and drainage of pus. The person
may have a fever, and blood sugar levels may be higher than
usual.
Diagnosis & Tests
How is the condition diagnosed?
Diabetic foot ulcers are usually first recognized by the affected individual.
The advice of a healthcare provider should be sought immediately. The provider
can diagnose the ulcer by looking at it. If the ulcer is draining fluid, a culture
of the fluid may be sent to the laboratory to check for infection.
Prevention & Expectations
What can be done to prevent the condition?
Prevention consists of following guidelines for foot care for people with diabetes. These guidelines include
regularly inspecting the feet and wearing shoes and inlays that fit properly.
What are the long-term effects of the condition?
If a diabetic foot ulcer isn't treated early and effectively, a person may
experience:
an infection in the ulcer itself
septicemia, an infection of the
bloodstream, which can be caused by bacteria from the ulcer
loss of function and ability to perform activities of daily living
amputation of the involved
foot
or leg
death
In the United States, people with diabetes account for 50% of nontraumatic
amputations. Most
of these amputations are below the knee. After a limb has been amputated, the
opposite limb is often lost within a few years. This happens not only because of ongoing
problems and vascular disease, but also because the opposite leg must bear
increased pressure and workload.
What are the risks to others?
A diabetic foot ulcer is not contagious and poses no risk to others.
Treatment & Monitoring
What are the treatments for the condition?
There are 10 major areas of treatment:
monitoring of peripheral vascular disease, which causes
decreased blood flow to the feet. Monitoring includes regular measurement of
oxygen levels in the skin, blood flow in the veins of the legs, and pulses in
the legs and feet. In some cases, imaging with special dyes and X-rays will be
used.
monitoring of diabetic
neuropathy,
or nerve damage from diabetes, in the feet
correcting risk factors. A person who
smokes should quit smoking. A
diet for diabetes should be carefully followed for blood
sugar control. Blood pressure and
cholesterol levels can be controlled with medication.
doing regular exercise for a person
with
diabetes, to improve circulation to the feet. The healthcare provider
may also prescribe special support hose to improve blood flow from the legs
to the heart.
aggressively treating any sign of skin damage. The treatment may consist
simply of local wound care and antibiotics. Infections, especially bone
infections, must be treated surgically. It is very important to
avoid pressure on the ulcer during healing because new tissue is delicate.
Prescription inlays, or shoe inserts, can be used to relieve pressure on the
area.
treating any fungal infections of the foot, such as fungal nail infections, with prescription medications
from
the healthcare provider
wearing well-cushioned walking shoes, athletic shoes, or special
prescription shoes as recommended by the healthcare provider
following a team approach to care. The team may include the person with
diabetes, the primary care physician, the physician's assistant, the diabetes educator,
the nutritionist, the surgical specialist and, if needed, a physician specializing in
diabetes.
performing daily foot care for a
person
with diabetes. In addition, the healthcare provider should examine the
person's feet at each visit.
learning about diabetes on an
ongoing basis. The individual must assume responsibility for self-care and
learn how to prevent ulcers.
What are the side effects of the treatments?
All medications have side effects. For example, some of the medications used to
treat diabetes may cause low blood sugar, known as hypoglycemia, which is potentially fatal. Surgery can cause
bleeding, infection, and allergic
reaction to anesthesia.
What happens after treatment for the condition?
After a person gets a diabetic foot ulcer, he or she will be at risk for further
skin breakdown and infection for the rest of his or her life. Informed
self-care and monitoring are the best tools available to prevent skin
lesions from becoming life- and limb-threatening infections. A neglected blister or callous is the most common reason for amputations in people with diabetes.
How is the condition monitored?
A person with diabetes needs to
follow
foot care guidelines and monitor blood sugar levels for the rest
of
his or her life. Foot inspection and monitoring of diabetes, as well as any
high
blood pressure or high
cholesterol, is also done by the healthcare provider.