What causes a Baker cyst?
Baker cysts are not uncommon and can be caused by virtually any cause of joint swelling (arthritis). The excess joint fluid (synovial fluid) bulges to the back of the knee to form the Baker cyst. The most common type of arthritis associated with Baker cysts is osteoarthritis, also called degenerative arthritis. Baker cysts can occur in children with juvenile arthritis of the knee. Baker cysts also can result from cartilage tears (such as a torn meniscus), rheumatoid arthritis, and other knee problems. What are symptoms of a Baker cyst? A Baker cyst may cause no symptoms or be associated with knee pain and/or tightness behind the knee, especially when the knee is extended or fully flexed. Baker cysts are usually visible as a bulge behind the knee that is particularly noticeable on standing and when compared to the opposite uninvolved knee. They are generally soft and minimally tender. Baker cysts can become complicated by protrusion of fluid down the leg between the muscles of the calf
