Synovial joints are the most common joints in the body and allow bones to move smoothly against one another. This lesson explains the joint cavity and the structures that reduce friction and stabilize the joint.
A synovial joint has a fluid-filled joint cavity between the articulating bones. The bone surfaces are not directly joined to one another by cartilage or fibrous connective tissue, as they are in cartilaginous or fibrous joints. Instead, they can move against each other within the cavity.
All flashcards
What is a joint cavity?
It is the fluid-filled space between the articulating bones of a synovial joint. The bones move against each other within this space.
What is the role of the articular capsule?
The fibrous articular capsule encloses the joint cavity and attaches to each bone just outside its articulating surface.
How does articular cartilage protect a joint?
This hyaline cartilage covers each articulating bone surface, providing a smooth layer that helps bones glide and protects underlying bone tissue.
What does synovial fluid do?
Secreted by the synovial membrane, synovial fluid lubricates the joint to reduce friction and provides nourishment to articular cartilage, which has no blood vessels.
How are ligaments classified by their relationship to the capsule?
Extrinsic ligaments lie outside the capsule, intrinsic ligaments are fused to or incorporated into its wall, and intracapsular ligaments lie inside it.
Quiz questions
Which structural feature distinguishes a synovial joint from fibrous and cartilaginous joints?Answer: A fluid-filled cavity between the articulating bones.
What is the primary role of a bursa near a joint?Answer: To separate structures that might otherwise rub against one another.
Which movement is characteristic of a pivot joint?Answer: Rotation around a single axis.
Which feature contributes to the hip joint’s greater stability compared with the shoulder?Answer: A deeper socket and strong supporting ligaments.
What causes gout in an affected joint?Answer: Deposition of uric acid crystals within the joint.
Based on Anatomy and Physiology 2e by J. Gordon Betts, Kelly A. Young, James A. Wise, Eddie Johnson, Brandon Poe, Dean H. Kruse, Oksana Korol, Jody E. Johnson, Mark Womble, Peter DeSaix (OpenStax), licensed CC BY 4.0. Adapted into a summary, flashcards and quizzes.