Systemic Lupus Erythematosus (SLE) is a chronic autoimmune condition where the immune system mistakenly attacks the body’s healthy tissues and organs. Joint involvement, including pain (arthralgia) and inflammation (arthritis), is one of the earliest and most frequent symptoms of lupus, affecting up to 95% of patients. While lupus can impact virtually any organ system, the musculoskeletal system is often the first to show signs.
The Characteristic Pattern of Joint Involvement
Lupus-related arthritis is characterized by a specific pattern that helps distinguish it from other inflammatory conditions. The inflammation is usually symmetrical, meaning corresponding joints on both sides of the body are involved. This arthritis is also polyarticular, affecting five or more joints simultaneously.
The small joints of the hands and wrists are the most commonly affected areas. This includes the metacarpophalangeal (MCP) joints (knuckles) and the proximal interphalangeal (PIP) joints (middle finger joints), which frequently experience tenderness, swelling, and stiffness. Other joints often involved include the knees and ankles.
A hallmark of lupus arthritis is its migratory nature; pain and inflammation may move quickly from one joint group to another over hours or days. Involvement of the elbows, shoulders, and hips is possible, but less common than in the smaller joints. Patients often report significant morning stiffness, a classic sign of inflammatory joint disease.
Non-Erosive vs. Deforming Joint Changes
A defining feature of most lupus arthritis is that it is non-erosive, meaning the inflammation does not typically destroy the bone or cartilage within the joint space. Unlike rheumatoid arthritis, where chronic inflammation causes irreversible structural damage, lupus damage is usually confined to the joint lining (synovium). This means that despite recurrent flares, the joint structure remains largely intact.
A less common presentation is Jaccoud’s arthropathy (JA), a non-erosive, deforming condition. JA results from chronic inflammation that causes the tendons and joint capsules to become lax and stretched. This joint instability leads to deformities such as ulnar deviation, where the fingers drift sideways.
In Jaccoud’s arthropathy, these deformities are often “reducible,” meaning a doctor can passively straighten the joint back into its normal alignment. This confirms that the bone and cartilage are not destroyed, distinguishing it from fixed, erosive deformities. The physical changes are a result of soft tissue damage rather than direct bone erosion.
Related Musculoskeletal Conditions
Lupus can cause inflammation and pain in the surrounding musculoskeletal structures beyond the joints themselves. Muscle pain (myalgia) is a frequent complaint, and some patients develop myositis, which is the inflammation of the muscle tissue. Myositis typically causes weakness, particularly in the muscles of the shoulders, hips, and thighs.
Inflammation can also affect connective tissues, leading to conditions like tendonitis (inflammation of a tendon) and tenosynovitis (inflammation of the protective sheath around the tendon). These issues cause pain and stiffness that mimics arthritis but originates outside the joint capsule.
A significant cause of joint pain is avascular necrosis (AVN), also called osteonecrosis, which is the death of bone tissue due to lack of blood supply. AVN is often linked to the use of high-dose corticosteroids, a common treatment for severe lupus flares. AVN most often affects larger joints like the hips, knees, and shoulders, causing deep, persistent pain distinct from inflammatory arthritis.
Managing Lupus-Related Joint Pain
Management of lupus-related joint pain focuses on reducing inflammation, controlling symptoms, and preventing long-term damage. For mild symptoms, non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or naproxen, are frequently used to control pain and reduce inflammation. NSAID use is monitored due to potential side effects, particularly in patients with kidney involvement.
Antimalarial drugs, such as hydroxychloroquine (Plaquenil), form the foundation of treatment for nearly all lupus patients with joint involvement. This medication reduces inflammation and helps prevent disease flares, though it can take several months to reach full therapeutic effect. For severe or persistent arthritis flares, a short course of low-dose corticosteroids, such as prednisone, may be prescribed to quickly suppress the immune response.
If symptoms resist initial treatments, doctors may introduce disease-modifying antirheumatic drugs (DMARDs) like methotrexate, or biologic agents. These medications modify the underlying immune system activity that drives inflammation. Non-pharmacological treatments, including physical therapy and gentle exercise, are also important for maintaining joint flexibility, muscle strength, and overall function.