What determines whether a joint is free moving or more rigid? Structure determines function.
The shapes of the bone surfaces in a joint determine which movements are allowed at a particular joint.
Sliding, gliding movement. - No axis of motion, one axis of motion, two axes of motion, multiple.
1 axis of motion, Hinge joints - Work in one plane, knee and elbow. Can only move in one plane.
Interphalangeal joints (IP joints) in fingers and toes.
2 axis of motion - wrist, ankle
3 axis, Ball and socket joints - Shoulder, hip
Shoulder moves in move directions, or planes, and thus can be dislocated from more directions. also the shape of the shoulder joint is more shallow than that of the hip joint???