An amphiarthrosis is a slightly moveable joint, such as the pubic symphysis or an intervertebral cartilaginous joint. A diarthrosis is a freely moveable joint.
A synchondrosis is a cartilaginous joint where the bones are joined by hyaline cartilage.
Diarthrotic: a freely movable joint.
A biaxial joint allows for motions within two planes. An example of a biaxial joint is a metacarpophalangeal joint (knuckle joint) of the hand.
The statement that the thumb is the only saddle joint in the human body is true.