How can diabetes affect my feet?

If you have diabetes you probably already know it’s essential to take special care of your feet. That’s because having too much glucose in your blood over a long period of time can cause serious complications, often before you realise there’s a problem. High blood glucose levels can trigger damage to nerves, known as neuropathy. This can cause a small cut to go unnoticed and become infected. You’re 15 times more likely to have a limb amputated if you have diabetes. Diabetes UK says about 80% of the more than 7,000 amputations a year in England alone related to diabetes could be prevented – so make sure you make foot care part of your daily routine.

What is diabetic neuropathy?

If you develop uncontrolled diabetes, it can damage your nerves. Damage to the nerves of the foot means you may become insensitive to heat, cold or pain. This is called 'sensory diabetic neuropathy'. There are a number of risks including:

• A small cut getting worse and becoming infected
• Muscles of the foot may not function properly due to nerve damage
• The foot may not align properly and create too much pressure in one area of the foot.

The NHS says about 1 in 10 people with diabetes develop a foot ulcer, which can result in serious infection.

What is peripheral vascular disease?

Another reason why people with diabetes have foot problems is because high blood glucose levels can damage blood vessels. This is known as 'peripheral vascular disease', which affects the blood supply to your legs and feet. Poor blood flow means cuts take longer to heal and puts you at risk of developing ulcers or gangrene – when tissue dies due to a lack of blood. Even if your feet may look pink and healthy, it’s important to check them regularly and have your nerves tested each year by an appropriately qualified healthcare professional.

Nerve symptoms

Detecting symptoms early is important to help avoid complications. Symptoms of nerve problems to watch for include:

• Tingling or pins and needles
• Numbness
• Pain
• Less sweating
• Redness or a hot sensation in the feet
• Changes in foot shape
• Hard skin
• Less sense of the position of your feet and legs

Blood supply symptoms

Check your feet regularly for blood supply problems including:

• Cramp in the calves
• Shiny or smooth skin
• Loss of hair on feet and legs
• Thicker toenails
• Cold, pale feet
• Changes in colour of skin on feet
• Sores or cuts
• Foot pain

Can common foot problems cause complications?

A simple injury or hard skin can potentially have serious complications if you have diabetes. Usually skin heals quickly, but with diabetes even common foot conditions need to be monitored carefully. The following slides outline conditions to watch out for.

Athlete's foot

If you have diabetes you have a higher risk of developing some skin problems, including fungal infections. Athlete's foot is a fungus that causes itching, redness, and cracking. It usually affects the skin between the toes. Germs can enter through the cracks in your skin and cause infection. Medicines that kill the fungus are used to treat athlete's foot. Your GP will recommend tablets or creams applied directly to the problem area.

Fungal nail infection

A fungal nail infection develops when a fungus attacks a fingernail, a toenail, or the skin under the nail. Nails may turn white, black, yellow or green; become thick and brittle; or separate from the rest of the nail. In some cases, the nail crumbles. The dark, moist and warm environment inside shoes can promote fungal growth. It can also happen after an injury to the nail. Fungal nail infections can lead to more serious problems if you have diabetes. They are also difficult to treat. Medications applied directly to the nail only help a small number of fungal nail problems. Oral tablets may need to be prescribed by your GP. Treatment also may include periodic removal of the damaged nail tissue.

Calluses

A callus is a hard, rough-feeling area of skin that can develop on your feet. The common callus usually occurs when a shoe rubs your foot. Calluses are caused by an uneven distribution of weight, generally on the bottom of the forefoot or heel. Calluses also can be caused by shoes that are too tight or by a skin abnormality. Some callus formation on the sole of the foot is normal, but if you have diabetes you need to be vigilant. During your routine visits, talk to your GP or diabetes nurse about preventing and treating calluses, cracks or broken skin. A podiatrist can also advise on the prevention and treatment of foot problems.

Corns

Corns usually develop on the tops and sides of the toes. A hard corn is a small patch of thickened, dead skin with a small plug of skin in the centre. A soft corn has a much thinner surface and usually develops between the toes. It can look white and rubbery. Seed corns are clusters of tiny corns that can be very tender if they are on a weight-bearing part of the foot. Seed corns tend to develop on the bottom of the feet, possibly due to blocked sweat ducts. Extra care is needed if you have diabetes and develop corns, and as with calluses should be treated by an appropriately qualified healthcare professional such as a podiatrist.

• After bathing, use a pumice stone and gently remove the build-up of tissue
• Avoid over-the-counter products to dissolve corns
• Never try to cut corns or remove them with a sharp object

Blisters

Blisters are pockets of fluid that can form on your feet as a result of rubbing, friction or burns. They are often caused by wearing shoes that don’t fit well, or wearing shoes without socks. If you have diabetes you need to take special care to avoid a blister becoming infected, which will need treatment from your GP. Never "pop" a blister as the skin covering it helps protect you from infection. Use an appropriate cream as advised by your doctor, diabetes nurse or pharmacist, and clean, soft bandages to help protect the skin and prevent infection.

Bunions

A bunion is a hard bony lump at the base of the big toe. It can hurt a lot and make it difficult to wear shoes. Bunions may run in the family and are more common in women. They are often a result of ill-fitting shoes. The foot becomes deformed as shoes put pressure on the big toe, pushing it toward the second toe. Padding the foot may help protect the bunion. A device may also be used to separate the big and second toes. If the bunion causes severe pain and deformity, surgery may be necessary.

Dry skin

If you have diabetes you may be more prone to dry skin. You may not sweat as much as usual, due to autonomic nerve damage. Very dry skin can crack and allow germs to get in and cause infection. Moisturising soaps and lotions can help keep your skin moist and soft.

The next couple of slides contain images of severe foot problems. If you are sensitive to images of this nature, please skip these slides.

Foot ulcers

As skin does not heal as quickly when you have diabetes, you’re more at risk of developing a foot ulcer due to a break in the skin or a deep sore. The skin around the wound may look darker and redder than usual. You may be able to see the tissues under the top layer of skin. The area may swell and fluid or pus may come out of the wound. Foot ulcers can develop after minor scrapes, or from the rubbing of shoes that don’t fit well. Identifying this kind of damage early is very important to help avoid serious complications. Seek medical advice right away if you have any concerns about your feet. In severe cases, surgery may be necessary.

Hammer toes

Hammer toes can be a problem if you have diabetes because of the risk of skin damage. The weakened muscle makes the tendons shorter, causing the toes to curl under the feet. Hammer toes can run in families or be caused by shoes that are too small. They can cause problems with walking and can lead to other foot problems, such as blisters, calluses and sores. Get medical advice if you develop a hammer toe. Splinting and corrective footwear can help treat the condition. In severe cases, surgery to straighten the toe may be necessary.

Ingrown toenail

Ingrown toenails develop when the edges of the nail grow into the skin. They cause pressure and pain along the nail edges. The most common cause is pressure from shoes. When toenails cut into the skin, it can cause pain, redness, swelling and infection. Trimming toenails regularly - cutting only straight across - helps to prevent ingrown toenails. Get medical advice if you develop an ingrown toenail, especially if you have a persistent problem or a nail infection. Severe problems with ingrown nails can be corrected with surgery to remove part of the toenail and growth plate.

Verrucas

Verrucas, also called plantar warts, are small bumpy growths on the soles or heel of the feet. They may have tiny black dots on the surface. Verrucas can be painful and may develop singly or in clusters. They are caused by a virus that infects the outer layer of skin. Do not use over-the-counter medications to dissolve the verruca if you have diabetes. See your GP who will confirm if it’s a verruca or a callus, and advise you on treatment.

Preventing foot problems

Preventing foot problems before they start is crucial if you have diabetes. There are health professionals who can help you keep your feet healthy but you are the one who needs to be vigilant and check your feet day to day. The following slides provide tips to help maintain good foot care.

Prevention – stay healthy

Prevention of foot problems starts with leading a healthy lifestyle and keeping your blood glucose levels under control. This helps ensure you prevent or slow down any changes to the nerves and blood vessels that supply your feet and legs. Follow your doctor’s advice on diet, exercise and medication and how frequently to check your blood sugar levels to make sure these stay within the desired range.

Prevention - daily checks

Establish a daily foot care routine and take steps to prevent damage to your feet. This includes checking your feet every day when you get up or before you go to sleep. Stick a post-it note in the bathroom as a reminder. Use a mirror if you find it hard to see underneath your feet. Check for a build-up of dry skin, sores, blisters, redness, calluses, or any of the foot problems listed in this slideshow. If you know you have circulation problems, it’s especially important to check your feet daily.

Prevention - hygiene

• Wash your feet in warm water every day using a mild soap.
• Dry your feet well, especially between the toes.
• Moisturise your feet daily with lotion recommended by your GP, diabetes nurse, or pharmacist.
• Do not put lotion between toes.
• Avoid soaking your feet.

Prevention - home care

You can deal with areas of dry skin at home by gently moisturising with a suitable cream or ointment. Do this after your bath or shower when your skin is soft and damp to help lock the moisture in. You can also clean small cuts and scrapes, by putting on antiseptic cream and using a dry sterile dressing. Check the wound regularly and if you see redness, swelling or oozing fluid, or if you are at all concerned, seek medical advice immediately. Also seek medical advice if you see any changes to your feet that last more than 2 days.

Prevention – nail care

If you have damage to the nerves and blood supply to your feet, don’t attempt to cut nails yourself, unless you have been shown how to do it by a podiatrist or nurse. You should be eligible for an NHS podiatrist if you have diabetes. If you can reach and see your feet well, take care of them carefully:

• Check your toenails at least once a week
• Cut nails when they have grown beyond the end of your toes (every 6 – 8 weeks)
• Trim your toenails straight across, never down the edges or at an angle
• Avoid rounding off the corners of toenails or cutting down on the sides of the nails
• Don’t use anything sharp to clean the side of edges
• After clipping, use an emery board to smooth edges of the nails.

Prevention - footwear

• Always wear shoes and socks that fit properly and aren’t too tight
• Wear socks at night if your feet get cold
• Avoid sandals and other open-toed shoes or slippers
• Avoid going barefoot around the house, in the garden or on holiday
• Choose shoes made of canvas or leather and break them in slowly
• Tailor-made insoles or orthotics, padding and arch supports can be supplied by podiatrists to relieve arch or heel pain.

Prevention – blood flow

If you have problems with your circulation, try to maintain blood flow around your feet by following these tips:

• Put your feet up when sitting
• Wiggle your toes and move your ankles several times a day
• Avoid crossing your legs for long periods of time.

Prevention – no smoking

If you have diabetes and you smoke, it’s important to stop. Smoking impairs your circulation and makes blood flow problems worse. Smoking can seriously increase foot and leg problems and lead to severe complications. You can get help from the NHS to quit smoking. Seeing an NHS stop smoking advisor can increase your chances of quitting successfully.

Prevention - check-ups

See a podiatrist at least once a year for a check up – even if you don’t have foot problems. You should be eligible for podiatrist care on the NHS if you have diabetes. Ask your GP for a referral to a local practitioner. An annual foot examination should include an inspection of the skin -- checking for redness or warmth of the skin. Get help from a GP or podiatrist immediately if foot blisters or injuries don’t heal quickly. You should treat ulcers urgently within 24 hours.

When to seek medical advice

Seek medical advice promptly if you develop any of the following problems:

• Breaks in the skin of your foot, or open sores or discharge, that are slow to heal
• Changes in skin colour to red, blue or darker, over part or all of the foot
• Skin on the foot is warmer or cooler than usual
• Swelling of the foot or ankle
• Leg pain
• Ingrown or infected toenails
• Corns or calluses
• Dry cracks in the skin, especially around the heel
• Unusual or persistent foot odour

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