Diarthrooseiksi

Diarthrooseiksi refers to the plural of diarthrosis, a class of joints in vertebrate anatomy that are freely movable. In English-language anatomy, the corresponding plural is diarthroses, and the singular is diarthrosis.

These joints are characterized by a synovial cavity and articular cartilage, surrounded by a fibrous capsule lined with a synovial membrane that secretes synovial fluid. Accessory structures include ligaments, tendons crossing the joint, and, when present, bursae and menisci or labra that help stabilize and cushion movement.

Movement is enabled by a fluid-filled cavity and a coordinated arrangement of bones, cartilage, and ligaments. Diarthroses are usually classified by the shape of the articular surfaces (plane, hinge, pivot, condyloid, saddle, ball-and-socket) and by the axis of movement (uniaxial, biaxial, multiaxial).

Examples of diarthroses include the knee and elbow (hinge joints), the hip and shoulder (ball-and-socket), the wrist (condyloid), the thumb carpometacarpal joint (saddle), and various gliding joints in the wrist and ankles (plane).

Clinical note: due to the presence of synovial fluid and cartilage, diarthroses are common sites of degenerative or inflammatory conditions such as osteoarthritis and rheumatoid arthritis. Injuries include ligament sprains, meniscal tears, dislocations, and synovitis.

Etymology and usage: The term “diarthrooseiksi” is used in Finnish-language texts as the plural form of diarthrosis. In English, the corresponding plural is diarthroses.