The Charcot Foot in Diabetes

Introduction:

Charcot foot was first reported in 1883. The other names of Charcot foot in diabetes are Charcot joint, neuropathic joint, Charcot arthropathy, Charcot neuropathic osteoarthropathy, or CN. Syphilis was believed to be the common causative factor till 1936. But now, diabetes is a common factor in etiology.

What Is Charcot Foot in Diabetes?

The Charcot foot in diabetes is a limb-threatening deformity seen in people with peripheral neuropathy (damage to peripheral nerves situated outside the brain and spinal cord) and diabetes. It can weaken the bone and joints, making them unstable and leading to deformity and disability. Most foot problems in diabetic patients occur due to damage to small blood vessels. Deficiency in blood supply to nerves will result in loss of sensation, making it challenging to feel wounds or other injuries. Delay in wound healing is another problem due to deficient blood supply to the skin and foot. As a result, diabetic patients get wounded easily, making it difficult to heal properly. In addition, bacteria that may enter these wounds lead to diabetic foot infections.

What Causes Charcot Foot?

Charcot foot is mainly seen in patients with nerve damage, which include the following:

• Diabetes: Nerve damage is most commonly caused by diabetes.

• Leprosy or Hansen's Disease: An infectious disease that is chronic and caused by the Mycobacterium leprae bacteria.

• Syphilis: An infection that is transmitted sexually and caused by the Treponema pallidum bacteria.

• Poliomyelitis: An infectious disease that is highly contagious and caused by the poliovirus.

• Syringomyelia: A condition caused by a fluid-filled cavity or cyst within the spinal cord.

• Abusing drugs and consuming too much alcohol.

• Spinal cord injury or disease.

• Infection, trauma, or injury to the nerve.

Other risk factors include:

• Aging.

• Obesity.

What Are the Indications and Symptoms of Charcot Foot in Diabetes?

The symptoms of Charcot foot can vary depending on the stage of the condition. Charcot foot initially manifests as swelling, redness, and warmth in the affected foot (warmer than the other foot). Mild pain and discomfort may also be present in some cases. These changes indicate signs of inflammation. Elevating the affected foot for several minutes is one method to differentiate Charcot foot and infection. In the case of Charcot foot, the swelling, redness, and warmth of the affected foot should improve.

Later the syndrome can progress through three clinical stages, which include:

• Stage One (Acute): Pain, redness, swelling, and warmth to the touch are the features of this stage. X-ray shows evidence of soft tissue swelling, minor bone fractures, and destruction of joints and surrounding bone. Loss of stability of joints may result in dislocation (separation of two joining ends of the bone). Fractures and dislocation may lead to severe deformities like rocket bottom foot deformity. This sign occurs due to the collapse of bone in the middle of the foot. This will cause deformation of the arch of the foot. The toes may start to curve like claws, and the ankle may also be deformed.

• Stage Two (Subacute): Coalescence (a fusion or blending of bones) is the feature of this stage. During this phase, the body recovers the damage caused by the initial stage. This slows down the destruction of joints and surrounding bones and promotes healing. Redness, swelling, and warmth get reduced. X-ray shows features of early bone healing.

• Stage Three (Chronic): Reconstruction is the feature of this stage. Redness, swelling, and warmth get resolved in this final stage. Joints and bone healing take place.

How Can Charcot Foot in Diabetes Be Diagnosed?

Charcot foot in diabetes can be diagnosed through the following:

Medical History: The doctor enquires and analyzes the cause of the foot injury. The doctor will also ask about the diabetic conditions, the recent glycated hemoglobin (HbA1c) count, and any history of infections or wounds in the foot.

Physical Examination: The doctor will look for signs of inflammation, including redness, swelling, and warmth in the affected foot. The doctor may lift the foot to observe if the symptoms improve. Ulcers and bony projections are also examined. The doctor will examine the foot's shape to rule out any deformities. They will analyze the blood flow and loss of sensation, if any.

Imaging Tests:

1. X-Rays: They give information about hard tissue structures like bones. X-rays may be normal in the early stages of Charcot foot. But in severe cases, fractures or bone fragments can also be identified from X-rays.

2. Computerized Tomography (CT) Scan: In cases requiring surgery for Charcot foot, the doctor may advise a CT scan that can provide a detailed three-dimensional view of the affected area.

3. Magnetic Resonance Imaging (MRI): It is performed when a detailed examination of soft tissues in the foot and ankle is necessary.

4. Bone Scan or Indium Scan: A nuclear medicine test can determine whether there is a bone infection. There are different types of bone scans available. It is up to the consulting doctor to decide on which type to go with. An indium scan is a diagnostic test performed by placing a marker on the white blood cells. A bone scan can return positive results in Charcot foot and bone infections. But increased activity on the indium scan can be observed only in cases of infection.

How Can Charcot Foot in Diabetes Be Treated?

The objectives of a Charcot foot treatment include taking the weight off the foot, preventing new foot fractures, and treating bone diseases.

Non-Surgical Treatment: Offloading is one of the most important non-surgical treatments. It is a process of immobilization or removing the weight from the injured foot. In the early stages of Charcot foot, offloading helps to reduce the signs of inflammation. Immobilization is done by inserting the injured foot into a cast or a detachable cast walker. Crutches or wheelchairs are advised to the patients to avoid putting any weight on the injured foot. A Charcot restrained orthotic walker (CROW) is also advised to prevent further foot injuries.

Surgical Treatment: Surgical treatment for Charcot foot is usually recommended when the above-mentioned non-surgical methods are ineffective, which include:

• Bone Fusion: Two or more bones are joined together in the foot to increase stability.

• Osteotomy: A bone in the foot is cut and reshaped to realign it and improve its function.

• Arthrodesis: The bones in the foot joints are merged to create a more stable structure.

• Amputation: Surgical removal of the affected limb to prevent further damage in severe cases of Charcot foot.

Conclusion:

Charcot foot is a long-lasting medical condition that gradually destroys bone and soft tissues at the weight-bearing joints. This can lead to difficulty in walking and performing day-to-day activities. Therefore, the treatment course generally begins with a non-surgical approach and proceeds to surgical options only if necessary. Even though a wide range of treatment options are available, prevention is the best way to deal with diabetic foot problems.