Diabetic Foot

Diabetic Neuropathy

The Patients with diabetes do not have normal feeling in their feet. The nerves stop conducting electrical impulses correctly as a result of the abnormal sugar metabolism. Sensations in the foot begin to change and decrease over time. This condition is called neuropathy.
There are two types of neuropathy. One is the lack of feeling and sensation, which leads to skin and bone problems. The other, referred to as autonomic neuropathy, is associated with changes in the skin texture and the moisture and oiliness of the skin. The combination of autonomic and sensory neuropathy leads to dry skin with scaling, fissuring and cracks, particularly on the bottom of the foot.
Treatment of neuropathy begins with good care of the feet. The feet should be inspected for sores and pressure areas twice daily. A mirror is often helpful. Socks should be changed frequently and there should be no pressure areas between the sock and the shoe. The shoe should be well padded and fitted by a shoe specialist (a pedorthist). A soft insole, called an orthotic support, should be used to protect and pad the foot from pressure. The condition of the skin must be maintained by soaking the feet regularly in room temperature water. Soak the foot daily for about 10 minutes and then rub in Vaseline to keep the skin soft and pliable. This will prevent cracks and fissures from forming. It does not appear that any medications or surgery can improve the condition of neuropathy.

Ulcers – Diabetic Foot Ulceration

Due to the neuropathy, light touch, deep pressure and most skin sensations cannot be adequately perceived. Any friction, rubbing, or pressure from a shoe will lead to an increased concentration of pressure on the foot. This causes skin breakdown and an ulcer develops. The pressure and friction are normal but the inability to feel these sensations is abnormal. The patient cannot make the fine-tuning and adjustments necessary to prevent an ulcer from forming. An ulcer is not caused by lack of circulation or by infection. The ulcers are usually associated with bone pressure and a bone prominence under the arch of the foot. These ulcers can become very large and must be treated.

If left untreated, the ulcer will lead to eventual bone infection and possibly amputation of the foot or leg. The most effective way to treat an ulcer is to change the pressure on the bottom of the foot. The majority of ulcers can therefore be treated with a walking boot, walking cast or a total contact cast. The cast distributes the pressure on the bottom of the foot allowing even pressure for walking and eventual healing of the ulcer. Complete healing takes anywhere from two to six months. If healing does not occur or if infection develops, surgery will become necessary.

Bone Disease (Charcot Neuropathy)
As a result of neuropathy, the nerve supply to bones and joints is not normal. From very minor trauma or prolonged walking, small areas of stress can build up in the bone or in a joint leading to a crack or a stress fracture. The patient is unable to perceive the pain from the stress injury and walking is continued. The stress crack in the bone now begins to get worse and develops into a fracture. The fracture also gets worse as more walking occurs on the injured foot or ankle. Very significant bone deformities can result from this condition, called Charcot Disease.

The most important aspect of treatment is to limit any weight bearing, walking and loading of the foot and ankle until the bone has healed. The goal of treatment is to prevent severe deformities of the foot from occurring and for the patient to be able to wear a shoe without difficulty. Continued walking with weight bearing can lead to very significant joint destruction and bone deformities. The treatment depends on the severity of the bone deformity at the time of diagnosis. Some cases require surgery immediately and others can be treated in a boot. The use of a boot or cast is important and no weight should be put on the foot until healing occurs. It can take up to a year for the bone to heal and the boot may have to be worn during this healing phase.