7. Synovial joints

It is also known as the diarthrosis joint. It is the most common and most movable type of joint in a mammal's body. It is a joint that connects two bones consisting of a cartilage-lined cavity filled with fluid.

 

As the bones in these joints are not physically connected, they can move more freely in relation to each other. This joint is composed of four prominent structures as follows:

  

It is a band of strong fibrous tissue that connects bone to bone.

 

It is a slippery fluid found within the joint cavity. It is of the egg-whites consistency. This fluid reduces the friction between the articular cartilage in the joint.

 

It is a cartilage that appears glassy-smooth. It is spongy and covers the ends of the bones in the joint.

 

It is a tough fibrous tissue that forms an envelope that surrounds the synovial joint. It has two layers, with the fibrous capsule lying outside the synovial membrane. The joint capsule helps strengthen the joint, and the synovial membrane lines the joint and secretes synovial fluid.

 

It is a condition that occurs due to friction of articulating cartilage or lack of synovial fluid in the joint. In such conditions, acute pain in joints, particularly while moving the joints, is observed.

Such a condition is known as arthritis.
Arthritis also occurs due to the deposition of uric acid crystals in the joints.