Charcot neuroarthropathy, also known as Charcot foot and ankle, is a syndrome in patients who have neuropathy or loss of sensation. It includes fractures and dislocations of bones and joints that occur with minimal or no known trauma. Charcot neuroarthropathy is a condition that affects the musculoskeletal system and is most commonly seen in the diabetic population along with severe peripheral neuropathy.
About twenty percent of patients with diabetes will develop a severe peripheral neuropathy, and as many as twenty-nine percent of these patients will develop Charcot changes.
Charcot often presents in the earliest stages with a red, hot, swollen extremity that may or may not be painful. However, the absence of pain cannot exclude the diagnosis of Charcot neuroarthropathy. In the early stages, the foot can feel like a bag of bones as the neuroarthropathy process causes the bones of the foot or ankle to break down.
Misdiagnosis of Charcot neuroarthropathy
Charcot neuroarthropathy is difficult to recognize because it can look like other conditions. For example, a red hot swollen foot could look like gout, bone infection, trauma, venous congestion or deep blood clots. Therefore, a high level of suspicion is necessary because any weight-bearing patient with peripheral neuropathy has the potential to suffer from Charcot. As many as 50 percent of patients may have had an inciting event leading up to a Charcot event. For example, a diabetic patient with peripheral neuropathy and an ankle fracture fixed with open reduction internal fixation may develop Charcot neuroarthropathy weeks later.
Chronic Charcot neuroarthropathy is often much more simple to diagnose. The foot often has gross deformity that is easily recognizable. What becomes more difficult is when the bony damage that is often evident on x-ray is mistaken for bone infection. The MRI results can also be mistaken for bone infection.
However, bony breakdown without a wound in a diabetic patient with peripheral neuropathy should always be suspicious for Charcot neuroarthropathy.
The syndrome progresses through three general stages:
- Stage 1 (acute, development fragmentation): marked redness, swelling, warmth; early radiographs show soft tissue swelling, and bony fragmentation and joint dislocation may be noted several weeks after onset.
- Stage 2 (subacute, coalescence): decreased redness, swelling and warmth; radiographs show early bony healing.
- Stage 3 (chronic, reconstruction-consolidation): redness, swelling, warmth resolved; bony healing or nonunion and residual deformity are frequently present.
Treatment for Charcot neuroarthropathy
Treatments for Charcot neuroarthropathy often depend on the stage of deformity. In acute Charcot, maintaining nonweight bearing is essential. Often a patient must remain non-weight bearing for many weeks to avoid any progressive deformity.
For example, during a Charcot event when the bones break down after a period of time, they will reform and often reshape like the bottom of a boat. These prominences can become areas of pressure and result in ulcerations, infections, and have the potential to lead to the loss of a limb.
The goal of any treatment is to reduce such abnormal foot pressures. Conservative treatments for chronic Charcot can be as simple as inserts for shoes, or even custom molded shoes. Many times, custom molded braces can help prevent calluses and possible tissue breakdown. This may be the only treatment needed if a foot is stable, braceable, minimally deformed and without ulcerations.
Chronic Charcot neuroarthropathy may be amenable to surgical intervention to rebuild the foot and decrease the deformity and pressures. This is where a foot and ankle surgeon experienced in the area of limb salvage and reconstruction can help. Reconstructive surgeries can often bring Charcot deformity and its complications into remission.
Each Charcot deformity is unique, and each patient requires a thorough evaluation with imaging to develop a treatment plan.