Bursitis is the inflammation of a bursa, which is a small, fluid-filled sac that acts as a cushion and gliding surface to reduce friction between tissues such as bones, tendons, and muscles near joints

. These bursae help facilitate smooth movement and reduce wear between moving parts in the body. When a bursa becomes inflamed, it causes pain, swelling, and stiffness in the affected joint, often limiting motion but usually not causing deformity

. Bursitis commonly affects bursae located near large joints such as the shoulders, elbows, hips, knees, and heels

. The condition often results from repetitive motion or sustained pressure on a joint, injury, infection, or underlying conditions like rheumatoid arthritis or gout

. Symptoms include localized pain, tenderness, swelling, warmth, and sometimes redness over the affected area

. Treatment typically involves resting the affected joint, applying ice, taking pain relievers like ibuprofen or paracetamol, and protecting the joint from further trauma

. In some cases, fluid may be aspirated from the bursa or steroid injections given to reduce inflammation. Rarely, surgical drainage or removal of the bursa is necessary

. In summary, bursitis is an inflammatory condition of the bursae that causes joint pain and swelling, commonly treated with conservative measures aimed at reducing inflammation and protecting the joint