The points of contact between your bones, tendons and ligaments are cushioned by small fluid-filled sacs called bursae (singular: bursa). When a joint is overused or injured, these bursae can swell up with extra fluid. As a result, they may push against the inner tissues within the joint, causing pain, inflammation, tenderness, and swelling. Bursitis may also be caused by an infection. If bursitis is left untreated, it can lead to pain and inflammation in the soft tissues, which may restrict the motion in that knee and cause pain when it is moved. Bursitis of the knee is also known as "Housemaid's Knee" because of the repetitive bending common to their work. The technical name for “Housemaid’s Knee” is prepatellar bursitis. Bursitis of the knee may also be referred to as anserine bursitis. Untreated bursitis may also lead to bone spurs, which will worsen the pain.