Submitted by Dr. Jakob Thorud, DPM, MS, FACFAS
Diabetes can lead to many medical conditions including neuropathy (nerve damage). Elevated blood sugars can lead to damage to the peripheral nerves resulting in sensation changes to the feet. Although burning and tingling pain caused by neuropathy is concerning, numbness to the feet is much more worrisome. This lack of sensation can lead someone with neuropathy to walk through pain that would otherwise have forced them to sit or at the very least check their foot. Someone could step on glass, rocks, needles, etc. and not notice until an infection has already taken hold. However, more frequently, the mere act of walking without sensation may lead to an area of high pressure and friction.
A callus may build over time but the pressure and friction does not stop as the person may not be aware of the concern. Eventually, the underlying skin may die and bleed underneath the callus leaving a dark spot within the callus. This wound is called a diabetic foot ulceration (or ulcer). At first, the ulcer may be covered by callus and not visibly drain or bleed. Unfortunately, bacteria can still reach the wound even if it is covered by callus and may lead to an infection. The ulceration will eventually open and may deepen to bone. Bone typically will become infected and requires more aggressive treatment to resolve. This can range from a long duration of antibiotics to amputations of the toe, foot or leg. To make matters worse, diabetes often results in impaired blood flow to the feet and may limit the delivery of antibiotics or make healing ulcerations or amputations more difficult.
It’s possible to limit or stop this progression of worsening symptoms to the feet, but early intervention is necessary.