Arthrocentesis – Aspiration of the joint

Capsule – Part of the synovial joint that, along with the lining, creates a pouch in which synovial fluid is secreted

Desmosomes – A small body that forms the site of attachment between cells

Hemarthrosis – The presence of blood in the joint

Monoarticular – Affecting a single joint

Pannus – A proliferation of synovium beginning at the periphery of the joint surface as seen in rheumatoid arthritis

Pigmented villonodular synovitis – A proliferative process of the synovial membrane of unknown etiology

Polyarticular – Affecting multiple joints

Primary synovial chondromatosis – A condition in which hyaline cartilage nodules grow within the synovial lining of a joint, bursa, or tendon sheath

Synovial fluid – The straw-colored fluid in the joint that is formed by filtration of capillary plasma

Synovial joints – Joints that have two opposing surfaces covered with articular cartilage and are attached at their periphery by the joint capsule

Synoviocytes – Cells that form the synovial membrane, remove debris, and secrete hyaluronic acid

Synovitis – A condition characterized by inflammation of the synovial lining

Synovium – A membrane-like lining of the synovial joints, tendon sheaths, and bursae

Type A synoviocytes – A type of synovial cell that plays a role in removing particulate debris from the joint

Type B synoviocytes – A type of synovial cell that secretes hyaluronic acid