A method of stabilizing a human spine is provided. The spine may be stabilized by inserting one or more dynamic interbody devices in a disc space between a first vertebra and a second vertebra. A dynamic interbody device may be inserted using an anterior approach. One or more dynamic interbody devices may be inserted using a posterior approach. One or more of the dynamic interbody devices may allow for coupled axial rotation and lateral bending of the first vertebra relative to the second vertebra. The spine may also be stabilized by installing one or more posterior dynamic stabilization systems.