Bursitis is a condition where the fluid-filled sac, or bursa, that cushions and protects a joint becomes swollen and irritated. The job of a bursa is to keep your joints moving smoothly, but sudden injury, overuse or repetitive motions can irritate the bursa, causing bursitis.
Even something as simple as leaning on hard surfaces for a long time, gardening or washing the kitchen floor can cause bursitis. The pain from bursitis can develop suddenly or build up over time.
Types of bursitis
Bursae act as padding between your bones, ligaments, muscles and tendons. You can develop bursitis wherever you have swelling or inflammation in a bursa.
One type of bursitis, septic bursitis, occurs due to a bacterial infection. However, many types develop as a result of overuse. Commonly affected joints include:
- Elbows (olecranon bursitis)
- Hips (trochanteric bursitis)
- Knees (prepatellar bursitis)
- Shoulders (subacromial bursitis)
- Feet, especially in the Achilles tendon, heel or big toe.