Natural synthesis of glucosamine occurs in the extracellular matrix of articular cartilage in joints. Capsular ligaments are part of the articular capsule that surrounds synovial joints. The fluid in articular cartilage effectively serves as a synovial fluid reserve. Both joint surfaces are covered with a strong but lubricated layer called articular hyaline cartilage. Proteins involved in autophagy are reduced with age in both human and mouse articular cartilage. There it will show as bone defect area under articular cartilage. In the thoracic region they are posterior to the pedicles, intervertebral foramina, and articular processes. The condyle can get locked in front of the articular eminence. Types of articular surfaces include trochlear surfaces. Modern amphibians have fully ossified vertebrae with articular processes. On the humerus there are extrasynovial fat pads adjacent to the three articular fossae. It has two articular surfaces named, proximal and distal articular surface. Plane joints permit sliding movements in the plane of articular surfaces. The jaw articulates via a hinge joint between the quadrate and articular. Meniscectomy, also termed discectomy refers to surgical removal of the articular disc.