Diffuse outgrowth arising from the SYNOVIAL MEMBRANE; SYNOVIAL BURSA; or TENDON sheath around the joint cavity, with extension to surrounding soft tissue. It is characterized by pigmented HEMOSIDERIN-containing MACROPHAGES; FOAM CELLS; and multinucleated GIANT CELLS. It usually occurs in the hands and feet, and around large joints, such as in the ankle and knee joints.
Diffuse outgrowth arising from the SYNOVIAL MEMBRANE; SYNOVIAL BURSA; or TENDON sheath around the joint cavity, with extension to surrounding soft tissue. It is characterized by pigmented HEMOSIDERIN-containing MACROPHAGES; FOAM CELLS; and multinucleated GIANT CELLS. It usually occurs in the hands and feet, and around large joints, such as in the ankle and knee joints.