Question

Which type of movement would have been possible if
1. our elbow had a fixed joint.
2. we were to have a ball and socket joint between our neck and head.

Answer 1

1. A fixed joint does not allow any movement. Thus, if our elbow had a fixed joint, we would not be able to bend/fold our arms.
2. A ball and socket joint allows movement in all directions. Thus, if we were to have a ball and socket joint between our neck and head, we would be able to rotate our head 360${}^{\circ }$.