Foot ulcers... peripheral neuropathy and diabetes
In the above title, are three entirely separate conditions. However, one cannot discuss foot ulcers without also discussing the two most contributory conditions; peripheral neuropathy and diabetes. First, let's define each condition.
An ulcer is a type of wound, and for our discussion, we will be talking about foot skin ulcers (not mouth or stomach ulcers). Usually, foot ulcers are the result of some kind of focal, repetitive injury, that results in a partial or complete skin breakdown.
Peripheral neuropathy: This is a condition affecting the nerves, most frequently in the lower extremities. It is usually a slowly progressive condition leading to some combination of both numbness and pain.
Diabetes is a metabolic condition affecting the entire body. However, for our discussion, we will focus on diabetes as the most frequent cause of peripheral neuropathy.
So now maybe it's becoming apparent that someone with diabetes (of which there is an epidemic) is at high risk of developing peripheral neuropathy. And neuropathy is the leading cause of foot ulcers. Neuropathy is an insidious condition, coming on so gradually, over years, that people often aren't aware it's happening. Eventually, it results in a loss of normal feeling, so that people begin to injure their feet, just in the course of normal walking, and yet they feel no discomfort. Also, their balance deteriorates.
In the picture on your right, is what a diabetic person with neuropathy might discover after coming home from playing tennis in ill-fitting shoes. They will be completely shocked and completely without pain.
Foot ulcers come in many forms. They can be big or small, deep or shallow, they can be infected or not. Most frequently they begin in the front part of the foot, either on the bottom or on the toes.
As podiatrists, we treat the vast majority of foot ulcers in the population. Often, the diabetic patient will show up in the clinic with his first foot ulcer, not understanding why they got this wound. One of the keys to treating foot ulcers is educating the patient as to why they got this wound, explaining the association of the wound to their diabetes, and identifying their neuropathy.
For completeness sake, I have to mention that foot ulcers can also be caused by poor circulation, either arterial or venous, and rarely by an autoimmune condition. But diabetic neuropathy is by far the leading cause.
Foot ulcers, left untreated, will inevitably become infected. Because there are so many bones in the foot, and the soft tissue layers over the bones are fairly thin, infections have a higher risk of penetrating to the bone. A bone infection (osteomyelitis) is a very serious, difficult to treat condition, that sometimes results in amputation of a toe, foot, or leg.
The picture on the right demonstrates an infected foot ulcer. notice spreading redness.
Treatment of ulcers involves multiple steps, each step directed at a part of the problem identified as the cause. The first step is removing the source of injury to the foot. This usually means guiding the patient toward better shoes. Often we also recommend custom-made diabetic orthotic devices, that are designed to work with the patient's feet so as to distribute weight evenly and prevent ulcers.
Diabetic shoes could look like normal shoes or might have to be something special, depending on the configuration of the foot. What makes Diabetic Shoes special is they are designed to have room for Diabetic Orthotics without crowding the foot or having to buy an oversized shoe.
The second step is the actual ulcer care. This is a broad topic. Books have been written on the subject, and medical journals completely devoted to this topic are published every month. Because feet are where most ulcers develop podiatrists are specifically trained in this type of wound care. Ulcer care usually involves debridement. This is a process of trimming, cutting or scraping away, callus or other non-viable tissues. The main reason for this is that non-viable (dead) tissues are unable to defend themselves against infection, and left in place, they become a food source for bacteria.
The third step in ulcer treatment is the wound dressing (the bandage). This is where a revolution of available options has taken place. We have dozens of options to choose from, all depending on the specifics of the wound and its location. Is the wound caused by diabetes, bad circulation, bad veins, or a combination of these problems? Is the wound wet or dry, infected or not, weight-bearing or non-weight-bearing skin, and many other decision points.
Outlined above is the typical treatment approach to foot ulcers, but in special cases other more esoteric means are employed, such as hyperbaric oxygen chambers, use of biological growth-promoting grafts and compounds, and more.