Diagnosis:
Like tendonitis, bursitis involves inflammation, but in a different part of the knee. Bursitis occurs in the bursae, which are fluid-filled cushions that minimize friction between bones, tendons and muscles. In each knee, there are 11 bursae that can become inflamed. Unlike tendonitis, bursitis most commonly occurs above the patella or below the knee joint.
Bursitis of the knee is typically found in athletes such as runners where overuse is common and can occur as a result of improper stretching or failure to stretch, tight hamstring muscles, obesity, or as a complication of osteoarthritis or a medial meniscus tear. In some cases, bursitis can be the result of a bacterial infection. The pain associated with bursitis is usually found inside the knee or in the center of the shinbone.