Synovial Joints Classification Quiz

Synovial Joint Classification

• Diarthrosis synovial joints are highly mobile, characterized by the presence of synovial fluid between bones.
• They allow for diverse movement types: uniaxial, biaxial, and triaxial (multiaxial) motions.
• All synovial joints fall under the diarthrosis category, confirming their high mobility.

Joint Types and Movements

• Uniaxial Joints: Bones move in a single plane or axis. Examples include hinge and pivot joints.
• Biaxial Joints: Bones move in two planes or axes. Condylar and saddle joints fall into this category.
• Multiaxial Joints: Bones can move in multiple planes. The ball-and-socket joint is an example.

Components of Diarthrosis Synovial Joints

• Articular Capsule: A joint capsule that encases synovial joints, retaining synovial fluid within.
• Articular Cartilage: Smooth cartilage (hyaline) that covers bone surfaces to facilitate joint movement.
• Joint Cavity: A hollow space within a joint containing synovial fluid.
• Synovial Fluid: Secreted by the synovial membrane, it serves to lubricate joints, nourish chondrocytes, and absorb shocks.

Specific Joint Definitions

• Plane Joint: Features flat articular surfaces allowing gliding movements; classified as uniaxial; examples include intercarpal and intertarsal joints.
• Hinge Joint: One bone's convex surface fits into the concave depression of another; also uniaxial; typical examples are the elbow and knee.
• Pivot Joint: A joint allowing one bone to rotate around another; categorized as uniaxial; examples are the atlantoaxial joint and radioulnar joint.
• Condylar Joint: An oval shape fits into a respective depression; classified as biaxial; the metacarpophalangeal joint exemplifies this joint type.
• Saddle Joint: Articular surfaces that resemble a saddle; also biaxial; an example is the carpometacarpal joint of the thumb.
• Ball-and-Socket Joint: Characterized by a spherical head fitting into a cup-like socket; classified as multiaxial; examples include the shoulder and hip joints.