Charcot foot

What is Charcot foot?

Charcot foot (Charcot neuroarthropathy) is a complication of diabetes. Nerve damage (peripheral neuropathy) leads to the gradual breakdown of the bones and joints of the foot. This can change the shape of the foot and raise the risk of ulcers¹.

The bones become fragile, so they may break or dislocate easily, even without a bad injury². Charcot foot is described as rare, but it is serious¹. If you have diabetes and reduced feeling in your feet, it helps to know the signs.

What causes it, and who gets it?

Charcot foot comes from nerve damage. It hasn't been reported in people without neuropathy³. Diabetes is the most common cause of neuropathy in developed countries, so people with diabetes are the main group affected¹.

It's more likely the longer you've had diabetes, and with eye damage, kidney changes (protein in the urine), high blood sugar levels or hardened arteries⁴. Other causes of nerve damage, such as toxins like alcohol, some infections and diseases of the spinal cord, can also lead to it³.

A minor injury often sets it off: about half of people remember one⁵. Because the foot is numb, you may not notice the injury or the damage that follows. In about a quarter of people, similar changes develop in the other foot⁵, so look after both feet.

What does it feel like, and how is it diagnosed?

Often it doesn't feel like much. The early signs are swelling and warmth in the foot or ankle, sometimes with redness that can be mistaken for infection². There's usually no pain because of the nerve damage, but not always, and usually only one foot is affected². So a missing injury or missing pain doesn't rule it out.

The picture can look like cellulitis (a skin infection), a blood clot in the leg or gout. For this reason it's often missed or diagnosed late⁶³.

Diagnosis starts with an examination. A podiatrist or doctor compares your two feet for warmth, swelling and redness, and checks that the skin is unbroken⁷. Swelling that goes down when you raise your leg points towards Charcot foot rather than infection⁵.

What treatment helps?

Charcot foot needs professional care from the start. If it's suspected, you'll be referred urgently to a diabetes foot team or an orthopaedic (bone and joint) team⁸⁹. A suspected case is treated as confirmed until proven otherwise, and treatment starts while you wait for scans to confirm it⁷.

Which treatment suits you is for that team to decide. It isn't clear yet which treatment methods work best¹⁰. Follow the team's advice closely.

If your foot isn't improving, go back to the team for a review and to talk about next steps. Any ulcer should be checked for infection⁵. A larger ulcer where bone can be seen raises the risk of infection in the bone⁵.

How long does it take, and how can I stop it coming back?

Charcot foot is serious, and it can carry a risk of amputation¹¹. Early action is your best protection. Delays in diagnosis contribute to worse outcomes⁶, and a delay of 8 weeks or more is linked with a much higher risk of problems⁷. Ulcers and infection are strongly linked with amputation after surgery on a Charcot foot¹², so new ones need prompt attention.

It isn't clear yet how long recovery takes or what best stops it coming back. Ask your diabetes foot team about a long-term plan for foot checks and footwear, and keep checking your other foot as well.