9. Joints: Functions and Classes

What is an articulation?

A joint where bones meet

What are the three functions of joints?

Enable movement

provide stability

let long bones lengthen

What is the functional classification of joints based on?

Based on amount of movement

What is a synarthrosis?

No movement

What is an amphiarthrosis?

Slight movement

What is a diarthrosis?

Free movement

Name the three functional classes from least to most movement.

Synarthrosis, amphiarthrosis, diarthrosis

What is the key relationship between movement and stability in joints?

More movement = less stability

What is the structural classification of joints based on?

Based on anatomy: what joins the bones, joint space or not

What are fibrous joints?

Joined by dense collagenous CT

no joint space

What are cartilaginous joints?

Joined by cartilage

no joint space

What are synovial joints?

Joint cavity with synovial fluid

always diarthroses

Which structural classes have no joint space

and what functional classes can each be?

Fibrous and cartilaginous

syn- or amphiarthroses

Match each structural class to its connector.

Fibrous: collagen CT

cartilaginous: cartilage

synovial: fluid-filled cavity

Rank the structural joint types on the stability/mobility continuum.

Fibrous (most stable) → cartilaginous → synovial; ball-and-socket most mobile