Charcot Joint Disease

Last Updated on January 31, 2021

Charcot joint or Charcot arthropathy is the name given to neuropathic joint disease is a condition that causes progressive destruction of bone and soft tissues of joints especially weight-bearing joints and may also cause disruption of the bony architecture.

Charcot joint disease can occur at any joint but most commonly in the lower extremity, at the foot and ankle.

Charcot’s joint is named after Jean-Martin Charcot. Syphilis was the most common cause of Charcot arthropathy until 1936, now it is diabetes.

The prevalence of Charcot arthropathy has been reported from 0.1- 13% in different studies. Bilateral disease occurs in less than 10% of patients. A slight male preponderance has been reported.

Causes of Charcot Joint

It is a neuropathic condition and any condition that causes sensory or autonomic neuropathy can lead to a Charcot’s joint. Charcot joint has been reported as a complication of following

Diabetes [most common cause]
Syphilis
Chronic alcoholism
Leprosy
Meningomyelocele
Spinal cord injury
Syringomyelia
Renal dialysis
Congenital insensitivity to pain.

Pathophysiology of Charcot Joint

The exact mechanism of Charcot joint disease is not known. Following theories suggest various mechanisms that may be responsible for this disease.

Neurotraumatic theory
- Microinjury to the insensate joint
- Continuous microtrauma leads to progressive destruction and damage
Neurovascular theory
- Increased blood flow in the limb due to preexisting condition
- Can result in an imbalance in destruction and synthesis
- Autonomic neuropathy leads to an abnormal bone formation
- Sensory neuropathy leads to an insensate joint that is susceptible to trauma.

Presentation of Charcot Joint

The clinical presentation of Charcot joint may vary from mild swelling and no deformity to moderate deformity with significant swelling depending on the stage of the disease.

Acute Charcot arthropathy presents with

Swelling
Increase in local skin temperature
Erythema over joint
Joint effusion

These features, in the presence of intact skin and a loss of protective sensation often point towards Charcot joint disease.

Typically, the pain minimal or when it is present, it is significantly less than the severity of joint involvement.

The patient may also have instability and loss of joint function.

Classification of Charcot Joint Disease

Saunders and Mrdjencovich classification is the most commonly used system. Their system classifies Charcot arthropathy of foot and ankle into 5 different patterns, as follows

Pattern 1- Involves the forefoot [interphalangeal joints, the phalanges, and the metatarsophalangeal joint]
Pattern 2- Tarsometatarsal joint
Pattern 3- Cuneonavicular, talonavicular, and calcaneocuboid joints
Pattern 4- Involves the ankle joint
Pattern 5- Involves the posterior calcaneus

Patterns 2 and 3 are the most common.

Lab Studies

Complete metabolic profile
Complete blood count
ESR
Glycosylated hemoglobin (HbA1C) for diabetes
Alkaline phosphatase, calcium, phosphorus, and parathyroid hormone for bony diseases like Paget

Vitamin B12/folate levels
- DEficiency could suggest peripheral neuropathy or chronic alcoholism.
Liver function tests
Coagulation studies may be done in chronic alcoholism.
Tests for syphlis

Imaging

Xrays help to confirm and stage disease and tell whether the disease is active. Osteopenia, periarticular fragmentation of bone, subluxations, dislocations, and fractures are usual finding in x-ray of Charcot joint depending on the destruction of the joint.

Bone scan can assist in differentiating between Charcot arthropathy and osteomyelitis.

MRI allows for anatomic imaging of the area. It also may help to distinguish between osteomyelitis and Charcot arthropathy.

Doppler ultrasound is used to rule out deep venous thrombosis.

Treatment

Treatment of Charcot arthropathy is primarily nonoperative.

Acute Phase

Cast immobilization
- Reduces joint stress
- For 3-6 months
Braces when casts are not suitable

Immobilization is discontinued when the disease process appears quite clinically, on x-ray and dermal thermometry

Patients are asked to reduce stress by remaining non-weight bearing or partial weight-bearing with crutches or walkers.

Follow up

After the removal of the cast lifelong protection of the involved limb is desired. Patients should wear a brace to protect the foot. A rocker-bottom sole can be used in presence of an ulcer. Plastazote inserts can be used for insensate feet.

The total healing process typically takes 1-2 years.

The major contraindication to surgery is active inflammation. Studies have shown less favorable outcomes when surgery is performed on an acute joint.