Sudden joint pain? Here are 10 common (and not-so-common) causes

Sudden joint pain, or arthralgia, can stem from various causes, ranging from viral infections like the flu and COVID-19 to chronic conditions. Post-viral complications and autoimmune diseases such as rheumatoid arthritis, lupus, and psoriatic arthritis can also trigger joint pain. Gout, caused by uric acid crystals, leads to intense pain and inflammation.