From the Guidelines
Yes, you can develop arthritis, specifically rheumatoid arthritis (RA), in your Metacarpophalangeal (MCP) joints, which are the joints at the base of your fingers where they connect to the hand. According to the study by 1, RA mainly targets MCP joints, PIP joints, and wrists. The differential diagnosis for hand osteoarthritis (HOA) is wide and includes conditions such as psoriatic arthritis, RA, gout, and haemochromatosis, which can also affect the MCP joints.
Key Points to Consider
- The diagnosis of RA and other arthropathies depends on a composite of clinical manifestations, radiographic changes, and laboratory tests 1.
- Certain features, such as non-proliferative marginal erosion, can be highly specific for RA 1.
- The 2023 EULAR recommendations on imaging in diagnosis and management of crystal-induced arthropathies suggest that ultrasound and dual-energy CT (DECT) are recommended imaging modalities for the diagnostic assessment of gout 1.
- However, in the context of RA, the diagnosis and management are more focused on clinical assessment, laboratory tests, and radiographic changes rather than imaging modalities like ultrasound or DECT.
Management and Treatment
- If you suspect RA in your MCP joints, treatment typically includes disease-modifying antirheumatic drugs (DMARDs) such as methotrexate (starting at 10mg weekly) or sulfasalazine (starting at 500mg daily), along with biologic agents like etanercept (50mg weekly) or adalimumab (40mg every other week) to reduce inflammation and slow disease progression.
- Lifestyle modifications, including maintaining a healthy weight, exercising regularly, and quitting smoking, are also important for managing RA.
- If your MCP joints are painful, swollen, and red, especially if you have a history of RA or other arthropathies, seek medical attention for proper diagnosis and treatment.
From the Research
Arthritis in Metacarpophalangeal (MCP) Joints
- Gout is a common inflammatory arthritis that can affect various joints, including the metacarpophalangeal (MCP) joints 2.
- A study published in 2007 found that ultrasonography can detect deposition of monosodium urate (MSU) crystals on cartilaginous surfaces, as well as tophaceous material and typical erosions in MCP joints 2.
- However, another study published in 2011 found that no urate deposits were found in MCP joints in patients with early gout 3.
- It is worth noting that gout is more commonly associated with the first metatarsophalangeal joint, and the prevalence of gout in MCP joints is not well established 4, 5, 6.
Gout and MCP Joints
- The double-contour sign, a hyperechoic, irregular band over the superficial margin of the articular cartilage, was not found in MCP joints in patients with early gout 3.
- Tophaceous material, represented by hypoechoic to hyperechoic, inhomogeneous material surrounded by a small anechoic rim, was seen in all gouty MCP joints in a study published in 2007 2.
- Erosions adjacent to tophaceous material were seen in 25% of MCP joints in the same study 2.
Diagnosis and Treatment
- Gout is typically diagnosed using clinical criteria from the American College of Rheumatology, and diagnosis may be confirmed by identification of MSU crystals in synovial fluid of the affected joint 4.
- Treatment of gout encompasses two strategies: firstly, treatment of inflammatory arthritis with non-steroidal anti-inflammatories, corticosteroids, colchicine, or interleukin-1 inhibitors, and secondly, urate lowering to a target of 0.36 mmol/L (6 mg/dL) or potentially lower in those with tophi 5.