The SARS-CoV-2 virus, which causes COVID-19, affects multiple organs beyond the respiratory system. Many individuals report musculoskeletal complaints post-infection, including persistent muscle aches and widespread joint discomfort. Researchers are investigating whether the virus can cause specific localized inflammatory conditions. The medical community is exploring the link between COVID-19 infection and the development of conditions like bursitis, a focused type of joint inflammation.
Understanding What Bursitis Is
Bursitis is a painful condition resulting from the inflammation of a bursa, a small, fluid-filled sac found throughout the body. Bursae function as cushions, reducing friction between bones, tendons, and muscles near the joints. When irritated or swollen, a bursa causes localized pain, tenderness, and stiffness. This condition most commonly occurs in large joints that undergo repetitive motion or pressure, such as the shoulder, elbow, hip, and knee. Non-viral causes include trauma, chronic overuse, and underlying conditions like gout or arthritis.
Medical Evidence Linking COVID-19 to Musculoskeletal Issues
Musculoskeletal pain is a common and often prolonged symptom following a COVID-19 infection, affecting patients in both the acute phase and as part of post-acute COVID syndrome (PACS). Studies show that over half of hospitalized patients report persistent musculoskeletal pain six months later, with joint pain (arthralgia) being frequent. Specific instances of bursitis have also been documented following COVID-19 infection. Case reports describe individuals developing subacromial-subdeltoid bursitis (shoulder inflammation) several weeks after a mild viral illness. Diagnostic testing often rules out typical causes like bacterial infection, suggesting a direct link to the preceding viral event.
The occurrence of new-onset joint inflammation, or arthritis, following COVID-19 has also been reported in medical literature. This post-infectious presentation, sometimes categorized as reactive arthritis, typically develops within a few weeks of the initial viral infection. This evidence suggests a strong correlation between the systemic effects of COVID-19 and the development of distinct inflammatory conditions affecting the joints and surrounding structures.
The Biological Mechanisms of Post-Viral Joint Inflammation
The connection between a respiratory virus and joint inflammation is explained by the body’s complex immune response. One primary mechanism involves systemic inflammation, characterized by elevated levels of pro-inflammatory signaling molecules called cytokines. During acute COVID-19, the immune system releases cytokines like Interleukin-6 (IL-6) and Tumor Necrosis Factor-alpha (TNF-α) to fight the virus. This release can cause widespread inflammation that affects distant tissues, including the bursae.
Another important pathway involves immune system dysregulation, leading to autoimmunity. The immune response designed to target viral proteins may mistakenly attack healthy tissues. This occurs when viral components resemble the body’s own cells, causing the immune system to attack joint linings or bursae. The presence of autoantibodies has been observed following SARS-CoV-2 infection, which can trigger conditions like reactive arthritis. Both systemic inflammatory overload and misdirected immune response contribute to the development of joint and soft tissue inflammation.
Treatment and Recovery for Bursitis
Managing bursitis involves conservative treatments focused on reducing pain and inflammation, regardless of the underlying cause. Initial care includes applying ice and taking nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, to control swelling and pain. Resting the joint and avoiding aggravating activities are also important steps in recovery.
If symptoms are severe or do not improve with home care, a physician may recommend further intervention. This can include a corticosteroid injection directly into the bursa to rapidly decrease inflammation and pain. Physical therapy is often prescribed to strengthen surrounding muscles, which helps stabilize the area and prevent recurrence. If an infectious cause is suspected, the physician may perform an aspiration to analyze the bursa fluid and prescribe antibiotics if a bacterial infection is confirmed. Anyone experiencing new or persistent joint pain after a COVID-19 infection should consult a healthcare provider for a proper diagnosis.