Lower extremity amputations are a tremendous source of illness, disability, and death for Americans living with diabetes. And these debilitating events aren’t a rarity, with a limb lost to diabetes globally every 20 seconds. The three most important factors in this are an impaired immune system (making it difficult to fight off infections), reduced nerve function (so there is no pain when a problem is developing), and reduced blood flow (which affects everything).
Diabetes can lead to a variety of skin problems, too often resulting in the development of aggressive infections. For example, chronic pressure to some specific area of skin causes thickening of the skin, what most would simply refer to as a callus. In the presence of the diseased nerves in the feet (neuropathy), these chronic calluses won’t hurt. When there is reduced blood flow to the feet and toes, the skin and soft tissues won’t be as healthy. Skin breakdown, what is technically tissue death, too easily results from recurrent stress to this tissue.
One of the most common sites for these problems to develop is at the tips of the toes. The digits are susceptible to changes in their positioning over the years, becoming angled up or down, even over adjacent toes. This process can occur for numerous reasons. The reduced nerve function associated with diabetes can lead to hammertoes when the muscles keeping the toe straight are no longer stimulated properly, a frequent product of diabetic neuropathy.
Hammertoes can also develop because of poor foot and leg mechanics. For example, very common is the individual with an arch that rolls down too much. This changes the pull of those muscles previously mentioned, the ones stabilizing the digits. Alternatively, hammertoes can develop in the high arched foot type, again, due to an imbalance in the tendons and muscles running out to the toes.
Regardless of the cause for the contracted digits, this alteration in positioning typically leads to excessive forces on some area of the toe on a regular, recurrent basis (as in daily). Initially, our skin reacts to this pressure by callusing, a natural and expected process. Our skin learns to make callus better with time, a slow but progressive change. Predictably, this results in a greater load on the living, viable tissues under the callus.
Due to clogging of their arteries, the tips of the toes tend to be poorly supplied with the precious life-giving fluid that is blood. One consequence is reduced viability, i.e. health, of the soft tissues in this area. But the chronic pressure from the deformed toe reduces further the already impaired blood flow. Skin death is a common result, often at the end of the affected toe.
It’s critical to remember these individuals have a reduced ability to feel certain sensations, like the gradual stress to their skin from some toe deformity. No specific symptoms may accompany diabetic neuropathy. A majority of those with neuropathy have no idea they suffer from poor nerve function. If specific testing of different types of nerves isn’t performed, no one may be the wiser. The afflicted will continue to live with the belief they will feel any developing skin injury.
Although numerous interventions are possible prior to the development of skin breakdown, too many of these individuals are never properly evaluated. When a dedicated diabetic foot evaluation is performed, these changes are recognized and the appropriate changes made. When this focused assessment doesn’t take place, historically, an excessive number of amputations eventually result. Depending on many factors, diabetic shoes may be all that is required, beneficial in this case because of the specialized material used for the innersole. Various pads and cushions can also help to reduce these stressors.
Certainly a surgical procedure can be used to straighten the toes. This can be a risky venture, taxing the individual’s blood supply, which is often inadequate. Many diabetics are leery of having this kind of correction performed, entailing increased risks of problems with healing (more common in diabetics), risks of infection, and prolonged immobility.
Underutilized is the simple release of a toe tendon. This can be achieved without an incision, a simple procedure, performed in the treatment room, with a needle stick. This can provide enough straightening of the digit to ease the pressure. Not all hammertoes can be corrected this way. But this simple one-minute procedure can sufficiently alter the inexorable process of skin death, infection, hospitalization, and amputation.
The procedure is termed a digital tenotomy. Armed with an intimate knowledge of the anatomy, this is a safe and reliable procedure. With its lack of soft tissue trauma, and the fact this is performed without an actual incision, complications are rare. No stitches are needed. It’s a simple needle stick requiring little more than a Band-Aid. This can be an extremely gratifying procedure in the diabetic population so affected.
For those who experience this event, major amputations (a foot or leg), typically alter activity levels, as well as causing a circulatory imbalance, with death the end-product most of the time (in the subsequent 5 years). But a measurable reduction in the number of major amputations is achievable. In diabetic foot medicine, the saying is, by saving a limb, we are saving a life.
Unfortunately, too many diabetics are never informed of these inexorable changes. If someone isn’t educated about the reduction in nerve function, they will assume the lack of pain indicates an insignificant problem. As the reader has been informed, this is commonly not the case. Bacterial invasion at the tips of the toes often will lead to bone infection or spread of the bacteria up the tendons into the deeper spaces of the foot. The involvement of this compartment in the foot has a poor prognosis.
The best medicine is prevention. Everyone with diabetes should be evaluated for their risk factors, as well as educated about proper diabetic home foot care. Hammertoes develop in many Americans and, for some, cause minimal problems. To someone with neuropathy and reduced circulation, they can start a deadly chain of events. All beginning with a bent toe. For many diabetics, a simple office procedure can prevent this cascade. We need to do better for our diabetics. We know how to prevent many of these unfortunate diabetic amputations. As a healthcare system, we have yet to do it.
EDITORS NOTE Dr. Conway McLean is :a podiatric physician now practicing foot and ankle medicine in the Upper Peninsula, having assumed the practice of Dr. Ken Tabor. McLean has lectured internationally on surgery and wound care, and is board certified in both, with a sub-specialty in foot orthotic therapy. Dr. McLean welcomes questions, comments and suggestions at firstname.lastname@example.org.