Diabetes and Feet...What’s the Big Deal?
by Dr. Christopher Segler
Whenever I have a new diabetic patient in my practice, I always ask them if they have know anyone who had a diabetic amputation. Almost all say yes. Then I ask if they know what happened to the friend, relative or co-worker that led to them losing the leg. In most cases there is some vague mumbling about an open sore or some kind of infection, but never any details. No real clear understanding of what transpired.
Shouldn’t every diabetic know the details so this could be prevented?
With each and every new patient with diabetes, they either fully comprehend the risks of diabetes to their feet (very rare) or they have no clue (very common). With every one of these folks I feel that the one goal is to get them to understand that diabetic foot problems are optional.
Diabetes can be a tough disease to deal with. Your doctor starts telling you what to eat, telling you to exercise, lecturing about heart attacks. Then you are at home learning about blood sugar monitoring, taking medicine, pricking your finger every day. Now I gotta think about my feet too? Seems like such a hassle.
And it is.
But the good news in all of this is that everything bad that can happen to you because of diabetes is preventable. Everything. All it takes is the right learning, a little lifestyle change, and little daily effort. The goal of this article is to get you to understand the basics of how diabetes can affect your feet...so you can do something about it.
When you have diabetes you have three main problems, all working together and conspiring against you, that can lead to a diabetic foot amputation. It involves your nerves, blood flow and immune system.
When your blood sugar is high, there is a chemical reaction that directly damages the ends of the longest nerves in your body. The longest ones start in your back (where they exit the spine) and head all the way down to the toes in one long piece. Because the ends get damaged first, any nerve damage starts in the toes and gradually creeps up the foot toward the ankles.
It is always damaged at the same level in both feet. For example, if you have nerve damage (neuropathy) at the ball of the foot, the nerve damage is only in the toes. In this case the arches and heels might be fine.
Neuropathy makes it hard for you to tell if you are getting a blister or an open sore, and puts you at risk for problems. It is deceptive because you might be able to feel other things like the position of your feet, shoes and socks squeezing, but not a blister, cut or sore.
The second problem is blood flow or circulation in the feet and legs. The arteries get clogged faster when you have diabetes. If you take two people who are identical except one is diabetic, the one who is diabetic is four times more likely to have a heart attack. That is because of the increased rate of clogging up those arteries through the process called atherosclerosis. But this process happens everywhere, not just the heart. The blood vessels to the legs get plugged up too. Then when you get a sore it takes longer to heal. It is also harder for your infection fighting white blood cells to get down there.
The last problem is your immune system. When your blood sugar is high, the white blood cells (called macrophages) have a hard to time fighting off those nasty bacteria. The white macrophages find bacteria through a process called chemotaxis. It is like following a trail of chemicals to its source. This is not very effective when the blood sugar is elevated. In effect, they are lost in the dark, simply bumping around hoping stumble into some bacteria to kill. Very inefficient and not very effective.
Once they do find the bacteria they have a bigger problem. The high blood sugar prevents them from eating the bacteria. The process where the white blood cells engulf the bacteria (called phagocytosis) is essentially disabled. So they bump up against they bacteria, but can’t do anything. Imaging a great white shark with his mouth wired shut trying to eat a smaller fish for dinner. Because of all of the this, the immune system is ineffective, the bacteria continue to grow and the infection quickly gets out of hand.
So an amputation goes something like this. You get a little nerve damage, can’t feel a blister starting, and it pops. Just like that, you have an open sore. Your blood flow is a little sluggish and takes a long time to heal. Then it gets infected while it is trying to heal. If you blood sugar is high, all of those sharks are wandering around in the dark, mouths wired shut, and the infection spreads.
If it spread enough, one of the bones gets infected. And a bone infection is the kiss of death for the diabetic foot. The only reliable way to heal a bone infection in an adult diabetic is to remove the infected bone. And that is where the amputation begins.
The moral of the story is watch your blood sugar, and your nerve damage will never get any worse. If you walk 30 minutes a day, fives days a week, your blood flow will never get any worse. If you have any nerve damage, you need close monitoring by a diabetic foot expert. If you ever get an any open sore, blister or ingrown toenail it is an emergency...no joke. Get that foot checked out or it might chopped off!
Dr. Christopher Segler is an award winning diabetic foot surgeon and podiatrist in San Francisco. He gets request from all over the United States for his information and expertise on treating diabetic foot infections and preventing diabetic foot amputations. You can view the abstract of the research he conducted that won 1st place from the American Podiatric Medical Association. His ground-breaking research helps podiatrists, foot doctors and diabetic foot surgeons determine the extent of a bone infection with MRI and may help them select the best treatment for the bone infection when surgery is required. Dr Segler makes podiatry house calls in San Francisco and can be reached at (415) 308-0833.