What Is Erosive Osteoarthritis?

Erosive osteoarthritis is an uncommon type of hand osteoarthritis. Compared with typical hand osteoarthritis (OA), this condition is more disabling and causes more severe joint pain and stiffness. Erosive OA is characterized by severe joint inflammation and bone breakdown, leading to characteristic X-ray findings, but it can also take longer to diagnose than typical OA.

Erosive OA affects approximately 3% of the general population. Women are affected more than men. However, it should be noted that the definition of this condition is not completely agreed upon by experts.

Advanced OA has a higher correlation with the occurrence of erosive changes, implying many people with erosive hand OA might actually have advanced hand OA. Also, there is significant debate over whether erosive OA is really its own disease or a phase of hand OA progression.

Symptoms and Signs

Erosive OA usually starts with a sudden onset of severe tenderness in multiple finger joints. The abrupt onset of symptoms is in contrast to the gradual progression of symptoms typical of hand OA.

You can also have variable degrees of:

• Redness
• Stiffness
• Warmth
• Swelling

Diagnosis

The diagnosis of erosive osteoarthritis can be a tricky process, as there is currently no set criteria. Your healthcare provider will consider your medical history, physical examination, and X-rays to ultimately make the diagnosis. Also, age, sex, diabetes, and obesity might constitute risk factors for the development of erosive hand OA.

Medical History

When you go to see your healthcare provider, they will ask about hand injuries, hand overuse, your own history of arthritis, and whether you have a family history of arthritis—especially rheumatoid arthritis (which closely resembles erosive OA). Studies have found first-degree relatives are at an increased risk of developing erosive hand OA.

Your healthcare provider will also ask if you have experienced systemic symptoms such as low-grade fever, rash, fatigue, or weight loss. While these symptoms don't typically occur with erosive OA, they can occur with inflammatory-type arthritis, such as rheumatoid arthritis or psoriatic arthritis.

Physical Examination

During your physical examination, your healthcare provider will check your hands for signs of swelling, tenderness, warmth, and redness. They will also test your range of motion and the strength of your fingers.

Stiffness and limited joint function tend to be more severe in erosive OA than in typical hand OA.

• In erosive OA, the distal interphalangeal joints (the joints closest to the fingertips) of the hand are most frequently involved, followed by the proximal interphalangeal joints (the joints closest to the knuckles).
• The metacarpophalangeal joints (knuckles of the hand) and the thumb joint are usually not affected in erosive OA.
• Although erosive hand OA might affect the first carpometacarpal joint and the interphalangeal joints, it rarely affects both.

Your healthcare provider will also look at the other joints in your body, such as your wrist and elbow joints. These are commonly affected in rheumatoid arthritis but not erosive OA.

Blood Tests

Blood tests tend to be normal in erosive OA. Your healthcare provider may order blood tests to rule out other diseases that could be causing your symptoms.

Blood tests you may need include:

• Erythrocyte sedimentation rate (ESR)
• C-reactive protein (CRP)
• Rheumatoid factor
• Anti-cyclic citrullinated peptide antibody

These tests may be abnormal in rheumatoid arthritis but should be within the normal range in erosive OA.

Imaging Tests

With erosive OA, hand X-rays will show central erosions, which are breaks in the bone surface at the center of the joint. This is known as the "gull-wing appearance."

With erosive OA, other changes on your X-ray can include:

• Osteophytes (bony growths)
• Subchondral cysts (cysts in the bone underneath the cartilage)
• Subluxations (partial dislocations)
• Ankyloses (joint stiffness and immobility caused by bone fusion)

In contrast, marginal erosions (bare areas on the sides), are seen in rheumatoid or psoriatic arthritis.

Treatment

Erosive OA can lead to deformity and impaired function of the hand, but there's little that can be done to slow the progression of the disease or change the prognosis. Treatment typically is focused on physical therapy and nonsteroidal anti-inflammatory drugs.

That said, in a 2019 clinical trial known as the Hand Osteoarthritis Prednisolone Efficacy (HOPE) study, 10 milligrams of prednisone, a steroid, showed promise as a treatment for hand OA, easing pain and decreasing inflammation after six weeks.

Other treatments for erosive OA have been considered, including a tumor necrosis factor inhibitor called Humira (adalimumab), which is a type of disease-modifying antirheumatic drug (DMARD). However, the European League Against Rheumatism (EULAR) does not recommend DMARDs for hand OA, as they've not proven effective for reducing erosions.

A small study also found magnetotherapy, commonly used in Europe, to be safe and effective for treating erosive hand OA. Magnetotherapy uses magnetic fields to reduce pain.

A Word From Verywell

While the precise diagnostic criteria and classification of erosive OA are still debated among experts, the severity (as compared to typical hand OA) and specific X-ray findings are hallmark features of the condition.

If you or a loved one has erosive OA, you should see a rheumatologist, which is a healthcare provider who specializes in treating joint disease. With early diagnosis and a treatment plan that includes medications and physical therapy, it is possible to optimize your joint health.