Other popular names
- Charcot Foot
Who does it affect?
Anyone with Diabetes, which is not uncommon, affecting some 6% of the population. Diabetic foot problems can be severe and inevitably require surgery. People suffering from diabetes generally face 2 problems: nerve damage and poor circulation. These conditions can result in the formation of blisters that can develop into serious and problematic infection within days. Chronic nerve damage (neuropathy) can cause dry and cracked skin, which often allows bacteria to enter and cause infection. This nerve damage in a diabetic patient may lead to the loss of sensation in the feet.
Diabetes also damages blood vessels, decreasing the blood flow to the feet. This poor circulation can weaken the bone and result in the disintegration of the bones and joints in the foot and ankle. As a consequence, people with diabetes are at a higher risk for breaking bones in the feet. With the problems associated with nerve damage and limited feeling, a diabetic patient may fracture a bone int he foot and not even realise this. Continuing to walk on the injured foot compounds the problems and more often than not, results in more severe fractures and joint dislocations.
The consequences are far and wide ranging, from the requirement for antibiotics to amputation of a toe or foot. For people with diabetes, careful, daily inspection of the feet is essential to overall health and the prevention of damaging foot problems.
Although a patient with Charcot (Diabetic) arthropathy typically will not have much pain, they may have other symptoms, which may include:
- Swelling of the foot. This can occur without traumatic injury.
- Redness of the foot.
- The swelling, redness, and changes to the bone that are seen on x-ray may be confused for a bone infection. A bone infection is very unlikely if the skin is intact and there is no ulcer present.
You are likely to require an x-ray, which will how fractures and dislocations of the joints.
The patient shown in the x-ray had noticed swelling of the foot for approximately 3 weeks without any known injury. The x-ray shows several fractures (arrowheads) and a dislocation of the first metatarsal (arrow). This type of traumatic injury is typically seen only after a high-impact event in patients without diabetes.
It is possible that you may require an MRI or Ultrasound scan. This will be requested if your Consultant wants to see more details of the soft tissue structures in the foot.
In situations whereby your Consultant suspects an infection in the bone, you may be required to undergo a Bone scan (DEXA) /indium scan. The details of this will be discussed at your Consultation.
Although in the majority of cases, Charcot will require surgery, if identified in early stages, there are a number of options open to your Consultant:
The early stages of Charcot are usually treated with a plaster cast or air boot to protect the foot and ankle. The use of a cast is very effective in reducing the swelling and protecting the bones. Casting requires that the patient does not put weight on the foot until the bones begin to heal. Crutches, a knee-walker device, or a wheelchair are usually necessary and healing can sometimes take 3 months or more. The cast will usually be changed every week or two to make sure that it continues to "fit" the leg as the swelling goes down.
After the initial swelling has decreased and the bones begin to fuse back together, a specialised custom walking boot or diabetic shoe may be recommended. The specialised shoe is designed to decrease the risk of ulcers (sores that do not heal). Some diabetics may not be able to wear regular, over-the-counter shoes because they do not fit the deformed foot correctly.
The goal of treatment for Charcot arthropathy is to heal the broken bones, as well as prevent further deformity and joint destruction.
Surgery may be recommended if the foot deformity puts the patient at a high risk for ulcers, or if protective shoewear is not effective. Unstable fractures and dislocations also require surgery to heal.
- Mild deformity with tightness at the heel. In some cases, the deformity is mild and associated with tightness at the back of the heel. Ulcers in the front of the foot that do not respond to a period of casting and protective shoewear, may be treated through Achilles tendon lengthening. Surgically lengthening the tendon that runs down the back of the leg and attaches to the back of the heel decreases the pressure on the midfoot and front of the foot. This allows the ulcer to heal and reduces the chance that it will return.
- Bony prominence on the bottom of the foot. A more severe deformity is the appearance of a very large bony bump on the bottom of the foot. If this cannot be addressed with shoe modification, it requires surgery. The type of surgery depends on the stability of the bones and joints in the foot.
- Stable deformity. Surgery involves a simple removal of the prominent bone by shaving it off. This may be done either arthroscopically or open.
- Unstable deformity. When the bones are too loose at the sight of the prominence, a simple removal of the bump will not be effective. The loose bones will simply move and a new prominence will develop. In this situation, fusion and repositioning of the bones is needed.
Fractures that occur in the softer bone of diabetics are typically more complex. Operations to fix them generally involve more hardware (plates and screws) than would normally be required in people without diabetes. The screws and plates may even be placed across normal joints to provide added stability.
The top x-ray shows that the patient has unstable Charcot of the back of the foot (hindfoot). The dislocation of the joints is seen where the two bones in the back of the foot do not line up (arrowhead). The bottom x-ray shows a complex realignment and fusion was performed to prevent the patient from developing a prominence and ulceration.
This operation is extremely difficult to perform and carries a higher risk of wound complications, infections, and amputation, compared to routine foot and ankle fracture surgery. After this type of operation, there is typically a period of no weight on the foot for at least 3 months. Placing weight on the foot early and failing to follow your Consultant's instructions will likely lead to complications, such as the return of the deformity or even worsening of the deformity.
- Ankle deformity. Charcot of the ankle is difficult to treat simply with a brace or shoe and commonly requires surgical fusion of both the ankle and the joint below the ankle (subtalar) to hold the foot straight. Given the amount of destruction of the bone and the poor quality of the soft tissue, the risk that the bone will not heal and the risk of infection are very high. Amputation may be required, either as the first operation or to salvage a fusion that has not healed or has became infected.
As there are numerous possible options for surgery, it is not possible to give exact guideslines on post-surgery rehabilitation. More often than not, surgery will be performed as a day case and you are able to go home soon after the operation. The anaesthetic will wear off after approximately 6 hours. Simple analgesia (pain killers) usually controls the pain and should be started before the anaesthetic has worn off. The dressing is removed soon after your operation. The wound is cleaned and redressed with a simple dressing. The sutures are removed at about 10 days.
General Care of the Diabetic Foot
- Never walk barefoot. The nerve damage decreases sensation so you may not notice that little pebbles or objects have gotten stuck in your foot. This can lead to a massive infection. Always wearing shoes or slippers reduces this risk.
- Wash your feet every day with mild soap and warm water. Test the water temperature with your hand first. Do not soak your feet. When drying them, pat each foot with a towel rather than rubbing vigorously. Be careful drying between your toes.
- Use lotion to keep the skin of your feet soft and moist. This prevents dry skin cracks and decreases the risk of infection. Do not put lotion between the toes.
- Trim your toe nails straight across. Avoid cutting the corners. Use a nail file or emery board. If you find an ingrown toenail, see advice from your Consultant. Good medical care is important in preventing infections.
- Do not use antiseptic solutions, drugstore medications, heating pads, or sharp instruments on your feet. Do not put your feet on radiators or in front of the fireplace.
- Always keep your feet warm. Wear loose socks to bed. Do not get your feet wet in snow or rain. Wear warm socks and shoes in winter.
- Do NOT smoke. Smoking damages blood vessels and decreases the ability of the body to deliver oxygen. In combination with diabetes, it significantly increases your risk of amputation not only of the feet, but can include the hands, as well.
Return to normal routine
Keep the wound dry until the stitches are out at 10 days.
Return to driving:
The foot needs to have full control of the pedals. You are advised to avoid driving until you have full movement and control back in your foot.
Return to work:
Everyone has different work environments. Returning to heavy manual labour should be prevented for approximately 4 - 6 weeks. Early return to heavy work may cause the tendons and nerve to scar into the released ligament. You will be given advice on your own particular situation by your Consultant.
Overall over 95% are happy with the result. However complications can occur. General risks (less than 1% each):
- Neuroma (nerve pain)
Reflex Sympathetic Dystrophy - RSD (<1% people suffer a reaction to surgery which can occur with any surgery from a minor procedure to a complex reconstruction).
Failure to completely resolve the symptoms results in less than 1% of patient