What is Charcot Arthropathy

Charcot arthropathy, also known as Charcot neuroarthropathy or Charcot foot and ankle, is a syndrome in patients who have peripheral neuropathy, or loss of sensation, in the foot and ankle. Patients may experience fractures and dislocations of bones and joints with minimal or no known trauma.

Symptoms

Initially, there may be swelling, redness and increased warmth of the foot and ankle. Later, when fractures and dislocations occur, there may be severe deformities of the foot and ankle, including collapse of the midfoot arch (often called rocker bottom foot) or instability of the ankle and hindfoot. The syndrome progresses through three general stages:

• Stage 1 (acute, development-fragmentation): marked redness, swelling, warmth; early X-rays 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; X-rays show early bone healing
• Stage 3 (chronic, reconstruction-consolidation): redness, swelling, warmth resolved; bone healing or nonunion and residual deformity frequently are present.

Causes

Charcot foot occurs in patients with peripheral neuropathy resulting from diverse conditions including diabetes mellitus, leprosy, syphilis, poliomyelitis, chronic alcoholism, or syringomyelia. Repetitive microtrauma that exceeds the rate of healing may cause fractures and dislocations. Changes in circulation may cause resorption of bone, weakening the bone and increasing susceptibility to fracture and dislocation.

Charcot arthropathy may affect any part of the foot and ankle. Multiple regions may be involved. Fractures and dislocations frequently involve several bones and joints, with extensive fragmentation and deformity.

Diagnosis

The time between the start of symptoms and a diagnosis may be several weeks or months. Often Charcot arthropathy is misdiagnosed initially because symptoms can mimic those of an injury or infection. Diagnosis is based on a high likelihood for this problem in patients with neuropathy. Increased redness, swelling, and warmth may be the only early signs. Immobilization and elevation can help to differentiate between infection and early Charcot. Some patients have pain. Early images may show soft tissue swelling with no bony changes, but repeat X-rays several weeks or months later may show bone and joint changes.

Treatments

• Non-surgical: Non-surgical treatment includes a protective splint, walking brace, orthosis or cast. Early weightbearing is allowed in stage one by 41 percent of specialists and in stage two by 49 percent of specialists, and other specialists recommend non-weightbearing. After stable healing is noted in stage three, treatment includes accommodative footwear with protective orthoses.
• Surgical: Select patients with instability in the early stages may be treated with open reduction and internal fixation and fusion. In the later stages, surgical options may include realignment osteotomy and fusion (correction of deformity) or ostectomy (removal of bony prominence that could cause an ulcer).

Recovery

Healing may take several months. Healing times after surgery may be twice the usual duration than for a non-diabetic foot. With Charcot foot and ankle, healing after fusion may require six months of protection and orthoses.

Charcot foot and ankle may recur or flare up. Also, it is common for both feet to be affected, which can make impairment permanent. Patients use protective footwear and orthoses, and limit standing and walking to that required for activities of daily living. Regular lifelong follow-up is required with a specialist.

Risks and Complications

Severe deformities may include collapse of the midfoot arch (called rocker bottom foot) with associated plantar midfoot ulcer. Deformities may occur in any part of the foot and ankle and result in ulcers from bony pressure against the shoe or ground; ulcers may become infected, and infections may be limb- and life-threatening. Some Charcot joints, such as the ankle, may heal with fibrous tissue (non-union) and this may result in gross instability (“floppy foot”) that may predispose to ulcers and may be difficult to support with braces.