With 285 million people suffering from diabetes worldwide,1 the disease has become a global epidemic.2 Twenty million people suffer from diabetes in the United States3 and more than six million of them are unaware that they have the disease. And the prevalence will increase as, according to an American Diabetes Association (ADA) forecast, an estimated 44 million people are likely to develop the deadly disease in the next 15 years.2
THE DIABETIC FOOT
One of the most significant complications of diabetes is the diabetic foot. Neuropathy, deformity, and/or repetitive trauma such as inappropriate footwear, are the most common causes of a diabetic foot ulcer.4,5 Fifteen percent of people with diabetes are estimated to develop foot ulcers.6 In addition to the economic costs, the emotional and lifestyle impact of having a foot ulcer or amputation is tremendous for the person experiencing this complication.7
Neuropathy plays a large role in the creation of an ulcer of the diabetic foot. If the person with diabetes has no feeling in his or her feet (loss of protective sensation), he or she is unaware of any issues that may be causing a foot ulcer. Due to obesity and/or vision problems commonly associated with diabetes, many diabetics cannot see their feet to conduct a self assessment. Often a diabetic foot ulcer is not found until it has been present for some time.
There are a large number of lower extremity amputations in people with diabetes. One third of them are at risk for amputation. Seventy to ninety percent of lower-limb amputations in people with diabetes were preceded by a foot ulcer.8 There were 71,000 nontraumatic lower-limb amputations performed on people with diabetes in 2004.3 People with diabetes have been identified as having the largest number of nontraumatic lower-limb amputations in the world.9 Every 30 seconds a lower limb is amputated somewhere in the world as a result of diabetes.
Footwear is the number one cause of trauma to the diabetic foot.10-12 The foot should be examined for any abnormal structures such as hammertoes, bunions, or amputations. Also, current shoes should be evaluated, looking for uneven wear and any worn areas inside the shoe that might indicate pressure areas. The shoe's toe box should be deep,13 allowing no pressure on the toes, and wide enough to avoid causing pressure on either side of the foot.
ASSESSING DIABETIC FEET
Take the time for a diabetic foot assessment. The person's history of ulcers and the current presence of ulcers should be discussed and become part of the diabetic foot ulcer care and prevention plan. Diabetic foot ulcers can be located on the plantar (bottom) of the foot, over the metatarsal (bones proximal to the toes) heads, on the heel, tips of the toes, and areas exposed to repetitive trauma (e.g., hitting on a shoe or brace). Characteristics of diabetic foot ulcers include even wound margins, deep wound bed, callus around the wound perimeter, the presence of granular tissue, and low to moderate drainage.5
Neuropathy contributes to the formation of wounds and ulcers on the diabetic foot. Limited blood flow, caused by poor circulation, makes it difficult for sores and infections to heal, and can ultimately lead to the amputation of a toe, foot, or leg. Evaluating blood flow to the diabetic foot includes palpating the dorsalis pedis and the posterior tibial arterial pulses and is a crucial part of the diabetic foot assessment.3,4,8,11,13-15
The ADA and the American Association of Wound Care identify the importance of prevention in reducing amputations of lower limbs in people with diabetes. A program already in practice for preventing amputations in persons with Hanson's disease has been adapted for the person with diabetes. It consists of:
annual foot screening
daily self-inspection of the feet
appropriate footwear selection
management of simple foot problems.9
Diabetic education is the key to prevention. Many patients with diabetes are not adequately educated about how to care for their feet. They need to be aware of their risk factors and how to manage them (e.g., once they buy the appropriate shoes, they need to break them in by wearing them for short periods of time to avoid getting blisters). If patients are unable to see their feet because of obesity, they need to learn how to examine their feet using a mirror or have someone evaluate their feet for them.