Dynamic intervertebral spacer implant

A method of fusing first and second adjacent vertebral bodies, each vertebral body having concave endplates facing each other, the method comprising:

• inserting a spinal spacer into an intervertebral space between the first and second vertebral bodies adjacent the concave endplates on the first and second vertebral bodies, the implant comprising a body having a generally central axis and a centralized aperture extending through the body near the centralized axis;
• the body further comprising:
• a first side having a first side perimeter and defining a first plane,
• the first side perimeter connected at a first edge with a perimeter wall;
• the first side comprising at least one lobe extending from the first perimeter toward the generally central axis;
• and
• allowing the first and second vertebral bodies to converge creating a load on the implant, so that the at least one lobe engages with one of the concave endplates;
• wherein the at least one lobe is adapted to deflect to a degree commensurate with the load.

A method of engaging first and second adjacent vertebral bodies, each vertebral body having concave endplates facing each other, the method comprising:

• inserting a spinal spacer into an intervertebral space between the first and second vertebral bodies, wherein the first and second vertebral bodies are in a first separated state;
• wherein the spinal spacer comprises at least one cantilever extending from a first location on a perimeter of a body toward a centralized aperture extending through the body;
• allowing the first and second vertebral bodies to converge to a second neutral state;
• wherein in the second neutral state one of the first or second concave endplates engage with the cantilever and the cantilever is adapted to deflect toward the other of the first or second concave endplates.