&Ischial bursitis=Ischial bursitis is also known as "weaver's bottom". Pain is present with sitting or lying down.  Bursa are fluid filled sack-like structure lined with synovial cells located around the body in areas where friction may develop between a bony prominence and overlying tendons. They allow normal movement and may communicate with a joint space. Bursa's are named by location: Bursitis is typically caused by trauma or overuse, but can be due to infection and inflammatory arthritis (gout or RA). The Bursa is characteristically swollen and tender on pressure