You’ve already had one leg amputated. Now you’ve noticed a sore on your other foot. You know that a wound precedes most nontraumatic amputations. If you aren’t already aware of these statistics, you should be: 42 percent of patients who have had a lower-extremity amputation will require an amputation on the other side within one to three years, and 56 percent will require a second amputation in three to five years. You’ve done all that you can to prevent the wound, but there it is. What do you do now?
First of all, don’t panic. Doctors who treat wounds have an ever-increasing arsenal of techniques to encourage wounds to heal. Before you go to the doctor, however, you need to minimize the damage. Cleanse the area gently with water or saline solution. If it is really dirty, you may use soap, but only for this first time. Soap can delay healing, so just use it once to clean the area. Apply an antibiotic cream and a sterile gauze dressing. Finally, the two most important things you can do are: Stay off of your foot and call your podiatrist!
Those of us who treat wounds frequently say: “Often, it’s not what you put on a wound that allows it to heal, it’s what you take off of it.” By that, we mean your body weight. Removing pressure from the foot is vital. If you have a wheelchair, use it. Crutches are also a valuable aid in removing weight from the foot.
Be sure to call your foot specialist soon after, if not before, you treat the wound. A wound on a person who has had a previous amputation cannot be taken lightly.
Your doctor should treat this as a potential medical emergency. He or she will ask you questions that will help determine how soon you need to be seen. If the wound is severe or infected, you may need a visit to the emergency room and may even need to be admitted to the hospital. Fortunately, new antibiotics are available to treat even the most resistant bacteria. Most of the time, they must be administered intravenously. You may, however, only need a trip to the doctor’s office for care.
What should you expect during your visit to your podiatrist for this new wound? Since you should have an ongoing relationship with a podiatrist, the doctor will already know most of your history. This may require updating your personal information, including any new medications, so take a list of your current prescriptions with you. If you have diabetes, your glucose control is important too, so bring along your log of glucometer readings. The doctor will examine your wound and evaluate its severity.
Your doctor will measure and grade the wound based upon a number of factors. The wound may be probed to see how deep it is. If the wound is deep, muscle, tendon and/or bone may be exposed. Odor or drainage may indicate the presence of infection. X-rays, MRI (magnetic resonance imaging) or bone scans may be ordered to more fully evaluate the wound. The area may be scraped and cultured.
The entire extremity must also be evaluated. Is the foot painful, or is it numb because of nerve damage? Is this neuropathy the cause of the ulcer (an open, nonhealing wound)? Is there a foot deformity such as a bunion or a hammertoe that has caused pressure and skin breakdown? How is the circulation? Is there enough blood coming into the foot to heal the wound? Can the doctor feel pulses? How are the skin color, texture and temperature? The doctor may order tests of the circulation or suggest a referral to a vascular surgeon (a circulation specialist). Blood tests may be needed to check on the status of an infection, on how well your body is responding and how capable it is to rise to the challenge of the wound.
Now that the wound has been evaluated, treatment may begin. In most cases, debridement will be necessary. During this procedure, any callus (hard skin) or dead tissue in the area will be removed. This may make the wound bleed or look bigger; this is normal. The podiatrist could also prescribe another form of debridement, such as an ointment with an enzyme that can “digest” dead tissue. Some doctors are using alternative debridement techniques, including the application of maggots. These insects eat the dead tissue in the wound, but leave healthy tissue intact. Topical antibiotic creams or ointments may be applied.
The wound must now be managed with some type of dressing. There are many types of dressings and dozens of brands, but they all have one primary purpose: keep the wound moist. It is not wise to let the wound “get air” and dry out. This drying process kills cells that are trying to heal the wound.
If the wound has little drainage, the prescribed dressings will often include a gel, which comes in tubes or in sheets, to moisten the area. Plain saline-moistened gauze may also be used, but must be changed at least twice daily to prevent the dressing from becoming dry. If there is drainage from the ulcer, the dressing should be able to absorb this moisture. These absorbent dressings include foam sheets, alginates (made from seaweed) and hydrocolloids (gel-forming agents). Many wound care products are now available with silver added. Silver acts to kill bacteria and helps to control or prevent infections.
Beyond the basic dressings are more exotic therapies. Some are truly exciting and have changed the way many wounds are treated. Growth factors are produced by the body to help heal wounds. In some cases, a wound may benefit from topical application of additional growth factors. There are now medications available that contain these genetically engineered growth factors, and they can be prescribed to “jump start” a wound that has not responded to conservative care. There are even bioengineered skin equivalents, basically skin that has been grown in a lab, that may cover a wound and add growth factors to the area.
Some wounds benefit from the use of a vacuum device that applies suction to the surface. This suction removes drainage, improves local circulation, helps control infection, and generally aids in wound healing. The application of oxygen to the wound, although controversial, also appears to help many wounds heal faster. The oxygen can be applied to the local area of the wound through a topical boot apparatus used at home or by lying completely enclosed in a hyperbaric oxygen tank that pushes oxygen into the body under concentrated atmospheric pressure.
In all cases, physical pressure must be removed from the wound. Your doctor may apply pads to the surrounding area or give you a special shoe. Crutches are valuable, as are wheelchairs. Special casts may be applied. The important thing to remember is, whatever the method used to remove weight from the wound, it must be used all the time. I have seen many wounds not heal because the patient has “only walked on it a little bit.”
If your foot specialist believes that the circulation to the area is inadequate for healing, you may be sent for a circulation test. Sometimes called a “Doppler test,” this noninvasive examination uses ultrasound to determine how much blood is getting to your foot. If the circulation is poor, you should be referred to a vascular surgeon for treatment.
One patient’s care illustrates many classic wound care principles. Mrs. G was a 68- year-old woman who came to the office with a “sore” on the bottom of her left foot. She didn’t feel any pain, but drainage from the wound had caused a stain on her sock, which led to her visit. Mrs. G has had diabetes for 15 years and said her glucose control has not been great. She already had a previous below-knee amputation of her other leg due to a similar problem resulting in a serious infection. She remembered how quickly the other foot had turned bad and came in sooner this time. I checked her sensation and found that she had very little feeling in her foot, typical of nerve damage called diabetic neuropathy. This is why she couldn’t feel the hole on the bottom of her foot! The pulses in her foot were fine, the skin was warm, and there was hair on her toes, so it was assumed that her circulation was pretty good. The wound wasn’t very deep and X-rays didn’t indicate any osteomyelitis (bone infection).
The wound had a large callus around the edges and fibers from her sock were embedded in the center. There was no redness or pus. Even though the wound was contaminated, there were no signs of infection. Mrs. G did not need antibiotics. The wound was debrided immediately. Since she was numb from the neuropathy, she felt nothing during the procedure. The large ulcer was measured so that we could track the healing as we progressed week to week. The area was thoroughly flushed with saline solution and a pad was placed around the hole to decrease pressure on the area. The wound was packed with a seaweed dressing to keep it moist but absorb excess drainage; a dry dressing then covered the entire area. The patient was instructed on how to change the dressings. She had a wheelchair, which she agreed to use as much as possible.
Mrs. G was referred to an endocrinologist to get her glucose under better control. She was also sent to a registered dietician to ensure her nutritional status was adequate for wound healing. Blood tests were ordered and she was advised to come back in a week.
What a difference a week made! Mrs. G did a great job of staying off of her foot and the wound’s size had decreased by 25 percent. Over the next six weeks, the wound continued to heal and minor changes were made in the treatment protocol. Once the wound closed completely, a custom-molded insole was made for her shoe to remove pressure from the area. Hopefully, this would stop the skin from breaking down again. Mrs. G now inspects her foot daily and promises to call at the first sign of local heat, redness or any opening in the skin. She understands that she must protect her remaining foot as if it were made from gold; after all, to her it is more valuable than the most precious metal on earth.
About the Author
Neil M. Scheffler, DPM, FACFAS, is a podiatrist in private practice in Baltimore, Maryland. He is a fellow of the American College of Foot and Ankle Surgeons and is board-certified in foot and ankle surgery. Dr. Scheffler is a past president, Health Care & Education, Mid-Atlantic Region, American Diabetes Association. He is the attending podiatrist for the Prosthetics Clinic, Sinai Hospital of Baltimore.