Question

Is a ball and socket joint a uniaxial joint because motion is limited to rotation in a single plane?

Answer 1

No.

Explanation:

Hinge joint can be said as uni-axial but ball and socket joint don't fit in the zone of uni-axial joints.
Because ball and socket joints are capable of providing movements in several directions. So, these function as multi-axial joints.
Examples:

• Hip joint
• Shoulder joint
  
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