Kneecap (patella) instability is a condition that causes the kneecap to shift, usually because of injury. Learn about symptoms and treatment.
About 65 percent of regular runners get hurt each year. It’s estimated that the average runner will sustain one injury for every 100 hours he or she runs.
Condition in which the bursae--fluid filled sacs at joint and muscle interfaces--become inflamed or irritated causing pain, swelling, and stiffness.