The synovium is the cell layer that constitutes the inner lining of the knee joint and other joints.
Synovium and the joint fluid
The synovium is smooth and glistening. It produces the joint fluid, which lubricates the joint and nourishes some of the structures within the joint.
Synovial fluid and synovial membrane mesenchymal stem cells: latest discoveries and therapeutic perspectives. de Sousa EB, Casado PL, Neto VM, Leite Duarte ME and Aguiar DP. Stem Cell Res Ther. 2014; 5(5): 112.