Foot care for diabetics
There are nearly three million people living with diabetes in the UK today. Diabetics have higher blood glucose (sugar) levels than normal because the body cannot use it properly and compensates by trying to flush it out as urine. The short-term effects of diabetes, namely tiredness, weight loss and increase in urine production, are well known. However, there are also long-term health complications and these can affect the feet of the sufferer in particular. The long-term complications involve neuropathy (nerve damage) and the circulation.
Diabetes and neuropathy
Up to a half of all patients with diabetes suffer with neuropathy. It is thought that diabetes causes neuropathy in two ways. Firstly, high blood glucose levels (hyperglycaemia) interfere with nerve signals. Secondly, the blood vessels that supply nerve cells with oxygen and nutrients become damaged. The common early symptoms of neuropathy are tingling, numbness and pain. There are three types of neuropathy and they all affect the feet.
Sensory neuropathy and the foot
Sensory neuropathy can lead to a loss of feeling and an inability to feel pain, temperature changes and vibration in the legs and feet. This is because the nerves that normally carry signals from the skin, bones and muscles to the brain are damaged. As a result, blisters or other small wounds do not send the usual pain signals that warn that something is wrong; the damage is not treated properly and infection and ulceration can follow.
Motor neuropathy and the foot
Motor neuropathy affects the nerves that send signals from the brain to the muscles and so control movement. When these nerves are damaged, the foot can alter shape because there is wasting (atrophy) of some of the small muscles.
Atrophy of one set of muscles can cause the instep (arch) of the foot to rise and become more pronounced causing the toes to curl and become clawed. If another set of muscles are affected the instep lowers or falls and causes flat feet.
Typical changes in the diabetic foot are hammer toes, claw toes and prominent metatarsal heads. The altered shape can cause areas of unusually high pressure at certain points on the sole of the foot; all of the weight of the body is concentrated on a small area. Over a period of time, the skin in this area will either break down (abrasions) or become calloused (hard). Foot callouses are prone to thickening, haemorrhaging and potentially ulceration.
Motor neuropathy of the muscles of the leg can affect gait (the way of walking) and reduce the capacity of the foot to absorb shock.
Autonomic neuropathy and the foot
Autonomic neuropathy primarily affects the sweat glands of the foot. Usually, sweat glands are regulated by nerves without conscious control. In diabetics, however, the nerve damage can result in too little sweat being produced. As a result the skin on the feet becomes dry and loses its elasticity making it prone to cracks and eventually to infection.
Diabetes and circulation
Diabetes affects the circulation of blood to the feet by causing the major arteries supplying the lower leg to ‘fur up’. This is a condition called atherosclerosis. The blood supply to the feet is reduced and ‘poor circulation’ results. High blood pressure, a diet high in fat and smoking add to this problem. Poor circulation in the feet can cause symptoms of cramp and pain; cuts and sores will not heal properly leading to a greater risk of infection and ulceration.
Serious foot problems in diabetes
Foot ulcers affect as many as 1 out of 10 people with diabetes and are taken extremely seriously. Even small ulcers may heal very slowly and need rigorous treatment. Untreated ulcers can develop into more widespread lower body infections, with the possibility of amputation of a limb in the worst cases.
Diabetic neuropathy that has remained undiagnosed may also become complicated by a condition called Charcot’s arthropathy. Within the foot, unnoticed pressure causes weakening of the bones and internal fractures. In worst cases this can lead to terminal ulceration and the need for amputation.
Self-care of foot problems in diabetes
There is no cure for the circulation and neuropathy problems that occur with diabetes. However, there are many techniques that an individual can use to protect the health of their feet and reduce the risk of more serious complications. Some self-care techniques and tips are outlined below. Further guidance can be obtained from your health care professional. It is very important to seek professional advice if you are at all concerned about any changes in appearance or sensation of your feet.
• Carefully control your blood glucose levels
• Control your cholesterol levels and blood pressure
• Eat a healthy diet and take regular exercise
• Avoid walking barefoot in areas where your feet could be damaged
• Wear well-fitting and comfortable socks and shoes
• Check your feet daily for signs of calluses, colour changes and breaks in the skin and treat appropriately. Ask for advice from a health care professional
• Wash feet daily and dry very carefully, you may wish to use an appropriate emollient cream
• Cut nails regularly and very carefully; get a podiatrist to do this if you can’t manage
• Have the condition of your feet reviewed regularly by a podiatrist
• Consider using insoles (orthotics) designed specifically for diabetics which will absorb shock and re-distribute weight so that pressure points are avoided
Diabetes and footwear
Wearing ill-fitting shoes is a particular risk for people with neuropathy and poor circulation. Corns, calluses, in-growing toe-nails, blisters and ulcers may go unnoticed and may not heal properly in diabetes sufferers so it is best not to get them in the first place. The best method of prevention is to wear well-fitting shoes that are broad, deep and rounded enough, are low heeled or flat and fasten with a lace or buckle so that the foot does not slide forward. If you are using diabetic orthotics you need to take them with you when trying on new shoes.
The more serious foot-related complications of diabetes can be avoided by using a combination of self-care techniques; appropriate footwear and orthotics (footlogics.co.uk) and a high level of vigilance together with support and advice from podiatrists and other health care professionals.