What Causes Bursitis?
If you overuse a joint in sports or on the job, put it under pressure for a long time, or get a sudden injury, a nearby bursa can get inflamed. The sac fills with extra fluid, which puts pressure on nearby tissue.
The first sign of trouble is pain, along with swelling and tenderness in the area.
Bursitis is different from tendinitis, which is inflammation or irritation in the cord, or tendon, that attaches your muscle to bone.