Which joint is the most mobile?

Which joint is the most mobile?

• A. Ball-and-socket
• B. Hinge joint
• C. Pivot joint
• D. Saddle joint

Answer: (A)

Mobility comes from how many axes and planes a joint can move in. A ball-and-socket joint has a spherical head that fits into a cup-shaped socket, allowing movement in multiple planes: flexion/extension, abduction/adduction, rotation, and circumduction. This multiaxial freedom gives it the greatest range of motion, seen in joints like the shoulder and hip. Hinges move mainly in one plane (flexion and extension) with limited sideways movement. Pivot joints rotate around a single axis. Saddle joints allow movement in two planes with some rotation, but not the full multidirectional range of a ball-and-socket. So ball-and-socket is the most mobile.

Mobility comes from how many axes and planes a joint can move in. A ball-and-socket joint has a spherical head that fits into a cup-shaped socket, allowing movement in multiple planes: flexion/extension, abduction/adduction, rotation, and circumduction. This multiaxial freedom gives it the greatest range of motion, seen in joints like the shoulder and hip. Hinges move mainly in one plane (flexion and extension) with limited sideways movement. Pivot joints rotate around a single axis. Saddle joints allow movement in two planes with some rotation, but not the full multidirectional range of a ball-and-socket. So ball-and-socket is the most mobile.