The effect of diabetes on the feet is a very important and often complicated subject. We will start out with the important basics and elaborate as we progress. A diabetic person can gradually lose both sensation and circulation to his or her feet as the disease advances. Properly controlling blood sugars reduces but does not eliminate the progression of these problems.

The loss of sensation for the diabetic is the greatest risk factor for developing foot infections, foot ulcers, or amputation. Also called peripheral neuropathy, this numbness or unusual sensation proceeds to rob the foot of its natural ability to sense irritation from shoes and everyday walking. The nerves lose their ability to conduct impulses due to nutrition changes in their small blood vessels, as well as changes in the nerves conduction membranes. Minor injury is ignored, leading to an infection, which can lead to an ulceration or amputation. Again, tight blood sugar control reduces the impact of the neuropathy.

Self help for the diabetic and his family includes the following:

1. Examine the feet daily for cuts, sores, blisters, drainage, bruised corns or calluses, warm or hot spots, bruised toenails, or infection. Use a plastic mirror to see the soles of the feet.

2. Consult your podiatrist or internist within a day or two if a minor injury does not heal, and immediately if an infection is suspected.

3. Keep your feet clean and dry, without soaking, and cut the toenails straight across. Thickened or fungus nail should be managed by a podiatrist.

4. Never go barefoot, wearing well-fitting comfortable supple leather shoes and cotton socks, even in the house, at all times.

5. Do not expose the feet to extremes of hot or cold, avoiding space heaters, hot water bottles, and winter exposure. Test bath water with your elbow before immersing your feet. Use socks and shoes only to aid in warmth for your feet.

6. Protect your feet with moisturizer and sunscreen.

7. Do not use over-the-counter products to remove corns or calluses, as the chemicals can damage the skin. Seek a podiatrist.

The diabetic should be looking at his feet regularly even if he has no pain. It only takes a day for a minor problem to turn into a major infection.

Maintain a healthy body weight. If there is any question about your blood sugar control, ask your doctor or health care professional if you should be monitoring your blood sugars at home. Also, an A1C test (glycosylated hemoglobin) should be done by your diabetes doctor every 3 months. You should ask the level and its meaning. The A1C is a more accurate assessment of your average control.

If you smoke, quit with your doctor's help. Tobacco is like a double dose of diabetes. The vessels to your skin and nerves become constricted by the nicotine.

The best exercise is low impact, such as walking, swimming, or bicycling. Avoid jogging, running, jumping or shearing types of exercise.

See a podiatrist for a foot exam yearly if healthy and quarterly if you are at risk.

Ask your family physician or podiatric physician to do the following:

1. Check the pulses and sensation in your feet.

2. Check your feet for bunions, calluses, and other deformities of the nails, skin, bones or joints.

3. Give you advice on how to care for your feet.

4. Give you advice on special shoes or inserts for your feet.

5. Consider a referral to another specialist member of the diabetic health care team.

Now Dr. Malusky is going to get into the more complicated aspects of diabetes and foot health. If you have accomplished the above recommendations, proceed for more detailed advice.

The podiatrist frequently has to function as the foot health gatekeeper for the diabetic patient who is assessed to be at risk for foot infection or ulceration. He may receive the patient as a referral from the hospital or primary care physician. The podiatrist may consider a direct working relationship with a vascular surgeon (for circulation problems), and the diabetologist or internist (for tighter sugar control). Additional consultations may include an infectious disease doctor, a cardiologist, neurologist, nephrologist, orthopedist, or diabetic teaching nurse. Additional professional services may be sought from radiology or nuclear medicine, a vascular laboratory, clinical laboratory, physical therapist, or orthotist.

About 15% of diabetics will develop a foot or leg ulcer at some time, often requiring hospitalization. Amputation rates are 15 times higher in diabetics than in nondiabetics, or about 60 per 10,000 individuals. Diabetics over age 65 have a rate of 102 amputations per 10,000. That's about 56,000 cases a year in the U.S., costing over $50 million. The rates are even higher in Blacks, Hispanics, and Native Americans. The 5 year survival rate after one leg is amputated is 40%. This is because the diabetic whose condition becomes deteriorated sufficiently to have an amputation, also frequently suffers from diabetic heart, kidney, or vascular disease. However, over 50% of these amputations could be prevented through the following means: proper foot care, patient education, early aggressive care of foot infections, surgery on the defective leg arteries as needed, and aggressively handling the diabetic's sugar control.

How does a diabetic foot ulcer develop? The major diabetic risk factors are neuropathy (loss of sensation), ischemia (loss of circulation), and trauma (abnormal stress or injury) to the foot. The three-point sequence of minor injury, followed by skin ulceration, complicated by the wound healing failure typical of poorly controlled diabetics accounts for most (70%) of the amputations. However, if the minor trauma incident can be removed from the sequence through proper footwear, patient education, and regular exams and care by a podiatrist, the rate of amputations would drop by greater than 50%.

There are many risk factors assessed by the team of doctors who evaluate a diabetic patient's chances of developing a foot ulceration. Health factors include neuropathy (nerve deficiencies to sensation, muscles and small vessels and glands), vascular disease (large vessels in the legs and changes to the smaller vessels' ability to conduct oxygen and nutrients to the tissue), and the poorly controlled diabetic's increased susceptibility to infection. Also, limb structure deformity, limited joint mobility, kidney disease, age, duration of diabetes, blindness, and prior ulcer history also contribute.

External risk factors for diabetic foot ulceration include mechanical trauma, high pressures on the sole of the foot, shoe gear pressure, and occupational or athletic foot impact. Thermal injury such as hot soaks, radiators, and frostbite may start the lesion. Chemical burns, including acid corn removers, ìbathroom surgeryî (a diabetics attempt at self care of foot lesions). The work environment poor knowledge of diabetes and its risks, cigarette smoking, and living alone are also risk factors.

Clearly, prevention is the key to reducing a diabetic's chances of developing an ulcer, infection, or amputation. The start is to maintain tight blood sugar control to forestall or reduce the onset of a diabetic's health risk factors. Regular visits, examinations, and foot care by a podiatrist are indicated. Risk assessment, early detection, and aggressive treatment of new foot lesions is undertaken. Proper foot gear may include cushioned walking shoes or extra depth custom molded shoes with foot orthoses or inserts, altering pressures on the sole of the foot. The podiatrist may consider prophylactic foot surgery, at an opportune time, to correct bunions, hammertoes, or offload previously ulcerated bony deformities. Charcot joint disease is a special subdivision of foot disease in the diabetic, where the non-feeling foot develops a washing-away effect of some joints. The neuropathy destroys the normally nerve-mediated small vessel flow control. The foot vessels at certain joints flow wide open. The foot may appear warm at a certain level. The foot collapses as the joints break down, and ulcers may develop as bones press downward.

The podiatrist and other health team members will instruct the diabetic on proper foot care, daily inspection, and management. A team approach to foot care in the diabetic is vital for this individual's ability to have a life free from foot problems.