In synovial joints the articular bones are separated by a fluid filled joint cavity, they are the only joints with a joint cavity
Synovial joints display five distinct features which include
- articular (hyaline) cartilage
- a joint cavity
- an articular capsule
- synovial fluid
- reinforcing ligaments
Synovial joints are diarthrotic and we find them predominantly in the limbs, where movement is of the essence and take precedence over support and protection.
In order of relative mobility we distinguish the following types of synovial joints (examples in brackets):
- plane (carpals, tarsals)
- hinge (knee, elbow)
- pivot (C1 adn C2, proximal radioulnar)
- condyloid (wrist)
- saddle (carpometacarpal joint of thumb)
- ball and socket (shoulder, hip)
That was just a quick glance at synovial joints, there will be more about them in the next couple of lessons.