Neuropathic Arthropathy

Neuropathic arthropathy is a rapidly destructive joint condition that develops when damaged nerves prevent you from feeling pain and injuries in your joints. Without the warning signal of pain, repeated injuries can cause severe joint damage, deformity, and disability.

Table of contents

• What Is Neuropathic Arthropathy
• Other Names for This Condition
• Causes and Risk Factors
• How the Condition Develops
• Symptoms and Signs
• Which Joints Are Affected
• How Doctors Diagnose the Condition
• Treatment Options
• Preventing Neuropathic Arthropathy

What Is Neuropathic Arthropathy

Neuropathic arthropathy is a condition where joints break down and become severely damaged because you cannot feel pain properly. This happens when nerves that normally send pain signals from your joints to your brain are damaged or not working correctly^[1]. The condition is also called a progressive fragmentation, which means the bones and joints gradually break into pieces^[2].

The arthropathy does not usually develop until years after the nerve damage begins, but once it starts, it can progress rapidly. In some cases, complete joint breakdown can happen within just a few months^[1][3]. When joint problems first appear, they may look similar to regular wear-and-tear arthritis, with joint stiffness and fluid buildup^[3].

Other Names for This Condition

Charcot joints, Charcot’s joints, Neurogenic arthropathy, Charcot neuroarthropathy, Diabetic arthropathy, Charcot foot

Causes and Risk Factors

Neuropathic arthropathy results from conditions that damage the nerves responsible for sensing pain and knowing where your body parts are positioned. When these nerves don’t work properly, you cannot feel when joints are being injured^[3].

The most common cause in the United States today is diabetes mellitus, which affects about 1 in 600 to 700 people with diabetes^[1][5]. The condition develops when blood sugar levels remain high for long periods, damaging the tiny nerves in the body^[3]. The second most common cause is stroke^[1][3].

Many other medical conditions can lead to neuropathic arthropathy. These include complications from untreated syphilis, spinal cord disorders and injuries, syringomyelia (fluid-filled spaces in the spinal cord), leprosy, alcoholic nerve damage, cerebral palsy, spinal birth defects, and inherited nerve disorders^[1][2][5]. Some people are born with an inability to sense pain, which also puts them at risk^[1][2].

The condition most commonly affects people aged 40 years or older who have obesity and peripheral neuropathy. It typically appears when someone presents with a swollen limb but reports minimal or no pain^[14].

How the Condition Develops

When deep pain sensation or awareness of joint position is impaired, the joint’s normal protective reflexes don’t work properly. This allows trauma—especially repeated minor injuries—and small bone fractures around the joint to go unnoticed^[1].

Injuries may happen from obvious traumatic events like falls or ankle sprains, but they can also develop slowly over time because of abnormal weight distribution on the affected limb. In a person with normal sensation, these abnormal forces would cause pain, making them automatically adjust their position before damage occurs. However, someone with nerve damage won’t feel pain or adjust their weight, so these forces continue causing fractures and other injuries^[13].

Two main theories explain how the arthropathy develops. The neurotrauma theory states that unperceived trauma or injury to a foot or joint that cannot sense pain is the primary cause. The neurovascular theory suggests that increased blood flow to bones from abnormal blood vessel widening results in active bone breakdown, contributing to bone and joint damage^[1][5].

Each new injury the joint sustains causes more distortion as it heals. Joints may fill with blood, and multiple small fractures can occur, speeding up disease progression. Loose ligaments, weak muscles, and rapid destruction of joint cartilage are common, making joint dislocations more likely^[1].

Symptoms and Signs

Pain is actually a common early symptom of neuropathic arthropathy. However, because the ability to sense pain is impaired, the amount of pain is often unexpectedly mild compared to how much joint damage is present^[1][3]. Despite this, roughly 75% of patients do experience some pain^[2]. If the disease progresses rapidly, the joint can become extremely painful, especially if there are bone fractures around the joint or tense blood-filled swellings^[1][3].

Early signs include prominent swelling, often with blood in the joint fluid, along with partial dislocation and instability of the joint. Acute complete joint dislocation sometimes occurs as well^[1].

The clinical presentation includes inflammation, redness, and increased skin temperature around the joint—the affected area may feel 3 to 7 degrees Celsius warmer than normal. There is diffuse swelling and warmth, but typically no changes to the skin itself^[2][14]. These findings in the presence of intact skin and loss of protective sensation are characteristic signs of acute neuropathic arthropathy^[2].

During advanced stages, the joint is swollen from abnormal bone growth and massive fluid buildup. Deformity results from dislocations and displaced fractures. Fractures and bone healing may produce loose pieces of cartilage or bone that break off into the joint^[1][3].

A coarse, grating, often audible grinding sound may develop when moving the joint. This sound is usually more unpleasant for observers than for the patient^[1][3].

Advanced joint destruction can cause significant changes to foot shape, including what’s called rocker-bottom foot, where the arch of the foot collapses. The foot may have a rounded bottom instead of its natural upward curve, with a bulge in the middle where the arch used to be. Toes may curl or curve under in a claw-like shape to help maintain stability. The ankle might bend or curve to one side and look noticeably less straight and stable^[9].

People with neuropathic arthropathy may develop foot ulcers or open sores. If the condition causes changes to foot or ankle shape, too much pressure can be placed on certain areas, increasing the risk of these infections^[9].

Which Joints Are Affected

Although many joints can be involved, the knee and ankle are most often affected^[1][3]. The condition can occur in any joint where nerve damage is present, although it most frequently appears in the foot and ankle^[2].

Which joints are affected depends largely on the underlying disease. Complications of untreated syphilis affect the knee and hip. Diabetes affects the foot and ankle. Syringomyelia commonly affects the spine and upper limb joints, especially the elbow and shoulder^[1][3].

Frequently, only one joint is affected, and usually no more than two or three joints are involved, except for the small joints of the feet. The pattern is typically asymmetric, meaning it doesn’t affect both sides of the body equally^[1].

How Doctors Diagnose the Condition

Doctors should consider neuropathic arthropathy when a patient with a nerve-damaging disorder develops destructive joint problems^[1]. The diagnosis should be suspected in any patient 40 years or older with obesity and peripheral neuropathy who presents with an acutely swollen foot following minimal or no remembered trauma and who reports minimal to no pain, particularly if x-rays and laboratory markers of infection are normal^[14].

Neuropathic arthropathy should also be considered in patients with a unilateral swollen limb and minimal or no associated pain, and in those with recurrent cellulitis but no systemic or laboratory findings concerning for infection^[14].

The diagnosis is made clinically and should be considered whenever a patient presents with warmth and swelling around a joint in the presence of neuropathy. Misdiagnosis is common—one in four cases of acute arthropathy is undiagnosed or misdiagnosed. The condition is most often confused with cellulitis, gout, deep vein blood clots, or a minor sprain^[2][14].

X-rays are essential for confirming the diagnosis. They can detect joint damage, which often includes calcium deposits and abnormal bone growth, as well as deformities. X-rays may reveal bone breakdown and degenerative changes in the joint^[2][3]. Weight-bearing x-rays of both feet are recommended to allow comparison and look for signs of subtle partial dislocations or ligament damage that indicate impending bone instability^[14].

If changes consistent with acute arthropathy are observed on imaging, or if early findings are unclear, magnetic resonance imaging (MRI) or computed tomography (CT) should be performed^[14].

Bacterial infection of the joint may develop with or without systemic symptoms like fever or general feeling of illness, particularly in people with diabetes. This requires doctors to have a high level of suspicion^[1].

Treatment Options

Treatment of neuropathic arthropathy has been primarily non-surgical. The major goal is to avoid ulceration, create joint stability, and maintain a foot that can bear weight properly^[2]. Treatment of the underlying nerve disorder can sometimes slow or even reverse joint damage^[3].

Treatment is carried out in two phases: an acute phase and a post-acute phase^[8]. Early recognition, patient education, and protection of joints through various methods of reducing weight-bearing are important in treating this disorder^[2].

Immobilization is usually accomplished by casting. Total contact casting has been shown to allow patients to walk while preventing the progression of deformity. Casts must be checked weekly to evaluate for proper fit and should be replaced every one to two weeks. Patients with accompanying ulceration must have their casts changed weekly for ulcer evaluation and cleaning^[8].

Immobilization should continue until lower leg swelling and warmth resolve, and serial x-rays show evidence of bone healing and strengthening^[14]. Casting is usually necessary for three to six months^[8]. Other methods of immobilization include metal braces and ankle-foot supports, but they may prolong healing times^[8].

Reduction of stress is accomplished by decreasing the amount of weight-bearing on the affected limb. Complete non-weight-bearing is ideal for treatment; however, patients are often not compliant with this. Studies have shown that partial weight-bearing with assistive devices like crutches or walkers is also acceptable without compromising healing time. However, full weight-bearing in the acute phase tends to lengthen total recovery time^[8].

Mobility aids like walkers, canes, wheelchairs, scooters, and special orthotic devices make getting around with a physical disability possible. Examples include knee walkers, convertible rollators (chair walkers), and specially designed boots that facilitate healing with minimal impact on mobility^[15].

Stabilizing painless fractures and splinting unstable joints can help stop or minimize the damage^[3]. Splints or special boots can sometimes help protect vulnerable joints^[3].

Surgery is warranted in fewer than 25% of cases and generally is used as a preventive measure. Surgery is performed when a deformity places the limb at risk of ulceration and when the limb cannot be safely protected in accommodative footwear. The goal of reconstruction is to create a stable foot that can be appropriately protected and can support walking^[8]. It may be considered in cases of advanced joint destruction, severe dislocation or instability, concern for skin breakdown, or failure of conservative treatment^[2][8].

The major contraindication for surgery is active inflammation. Studies have shown less favorable outcomes when surgery is performed on an acute joint^[8]. Hip and knee joints may be surgically repaired or replaced with an artificial joint. However, people are at a higher risk of complications, such as the artificial joint loosening and dislocating^[3].

Preventing Neuropathic Arthropathy

The best way to prevent neuropathic arthropathy is to have regular checkups with a healthcare provider and examine your feet for any loss or change in your ability to feel touch, pain, or pressure^[9]. If you have diabetes, strict blood sugar control and careful, daily inspection of the feet are essential to both overall health and the prevention of devastating foot problems^[13].

Sometimes neuropathic arthropathy can be prevented by taking care of the feet and avoiding injuries^[3]. It is important to make several changes to your home to improve safety. Eliminate tripping hazards like clutter, area rugs, and uneven flooring. If you are using a mobility aid at home, arrange furniture so that you have plenty of space to move around. Wear house shoes for comfort, protection from stubbed toes, and non-slip footing. Install grab bars and handrails, especially in bathrooms and on stairs^[15].

Managing and correcting contributing conditions such as diabetes is critical. If neuropathy is related to nutritional deficiencies, supplements may help. If it is related to a medical condition such as diabetes or thyroid problems, treating the condition can sometimes reverse the symptoms^[9].

Daily foot inspection is essential. Look for blisters, cuts, cracks, or sores. If you cannot see well, use a mirror or have someone help you. Wash your feet every day with warm (not hot) water—check the water temperature with your wrists, not your feet. Dry your feet well, especially between your toes. Use skin cream to prevent calluses and cracks, but do not put cream between your toes^[20].

Trim and file your toenails straight across to prevent ingrown toenails. Change socks daily—they should be thick and cushioned and fit loosely. Look inside your shoes every day for things like gravel or torn linings that could cause blisters or sores. Buy shoes that fit well with plenty of space around the toes. Do not go barefoot, and do not wear sandals or shoes with very thin soles^[20].

Lifestyle changes can help reduce or prevent symptoms. Stop or correct movements and postures that cause repetitive damage. Eliminate excessive consumption of alcohol and tobacco. Follow nutrition plans high in vitamin B-12, including fruits, vegetables, and lean forms of protein such as fish or eggs. Engage in routine exercise at least three times a week for 30 to 60 minutes^[19].