Expanding intervertebral implants

A method for stabilizing bones comprising:

• providing a device for separating bones of a joint using a driver tool having a threaded shaft, the spacer having:
• a superior endplate having a bone engaging surface and a surface opposite the bone engaging surface, and ramps including at least two inferior facing ramps;
• an inferior endplate having a bone engaging surface and a surface opposite the bone engaging surface, and ramps including at least two superior facing ramps;
• first and second bearings disposed between the first and second endplates, each having ramps including at least one superior facing ramp mateably engaged with an inferior facing ramp of the superior endplate, and at least one inferior facing ramp mateably engaged with a superior facing ramp of the inferior endplate,
• the first bearing including a threaded aperture, the second bearing including a thrust surface, the threaded aperture threadably engageable with the threaded shaft of the driver tool,
• the thrust surface aligned with the threaded shaft to be pushable by the threaded shaft when the threaded shaft is threaded through the threaded aperture to thereby cause the first and second bearings to be driven apart, whereby the ramps of the first and second bearings bear against the ramps of the superior endplate and the ramps of the inferior endplate to thereby push the superior endplate away from the inferior endplate,
• wherein the threaded aperture is disposed at a non-orthogonal angle with respect to a longitudinal axis of the device, and
• positioning the spacer between adjacent bones using a lateral approach.