Charcot Neuroarthropathy is a neauropathic joint disease that is a common complication of diabetes. Problems that occur as a result of this disease are fractures, dislocations, and rapid destruction of foot joints. The diagnosis of Charcot neuroarthropathy is made clinically after observing a lack of normal foot sensation, presence of ulcerations, and presence of foot deformity due to joint dislocation. It is a chronic and progressive joint disease that leads to the destruction of joints and surrounding bony structures and may lead to amputation if left untreated. Charcot neuroarthropathy commonly occurs in the foot and ankle, but can also occur in the shoulder, the elbow, and the knee. While most patients with Charcot neuroarthropathy have type 2 diabetes, other risk factors have been identified, including:
- Syphilis (tabes dorsalis)
The cause of Charcot neuroarthropathy is not well understood but there are two major theories: a neurovascular theory and a neurotraumatic theory. The neurovascular theory states that increased blood flow (hyperemia) to the limb causes bone resorption and weakening. Increased blood flow is thought to be caused by dilation of the blood vessels due to denervation of the nerves.
The neurotraumatic theory states that patients experience an overuse injury due to a lack of protective sensation. The nervous system protects the body by sending adverse signals when part of the body is in harm, forcing the body to adjust. Without these sensations, the body’s normal protective mechanisms (e.g. body-weight shifting, limiting activity, and muscle guarding) are absent, causing injury over time. The mechanism for Charcot neuroarthropathy is probably a combination of both theories.
Various stages of Charcot neuroarthropathy have been identified:
- Characterized by swelling, warmth, joint instability, and normal anatomy
- Characterized by fragmentation of bones and cartilage, joint dislocation, soft-tissue edema, hyperemia, bone resorption, and intra-articular fractures
- Characterized by decreased soft-tissue edema, organization of bone fragments, and fracture heaing
- Characterized by new bone formation and bone remodeling
Charcot deformities of the foot and ankle can vary considerably in terms of severity and location. Generally, the Charcot foot is larger in size than a normal foot. The clinical presentation will vary depending on the stage of the disease. Stage 1 presents like an infection: a swollen, warm foot. Chronic (stages 2 and 3) Charcot foot presents with severe foot and ankle deformities.
Ulceration and infection is commonly associated with Charcot neuroarthropathy. Chronic ulcerations can lead to osteomyelitis (bone infection). In these cases, the infected bone should be resected before or during reconstruction.
At the Paley Institute, we have treated the full spectrum of the sequelae of Charcot neuroarthropathy. We can stabilize the foot with an external fixator, reconstruct the bony deformities, and address the ulcerations with wound healing. During the initial consultation, we will assess the foot and ankle, including ulcerations and osteomyelitis, and use x-rays to determine the location and severity of the boney deformities. Treatment depends on the stage of the disease, the anatomic location of the deformity, the presence or absence of osteomyelitis (bone infection), and the stability of the foot.