Thermal memory springs may form arches, or have coils or spring arms and truss arms that expand from a relaxed state when the thermal memory springs warm to a temperature that is about the body temperature of a human being. The thermal memory springs may be used to expand interbody implants from a compact state into an expanded state once the implant has been inserted into the desired location within the body and the thermal memory springs that form a part of the implant warms to body temperature. Ends of the expanded thermal memory spring may contact a bone surface, thereby being an anti-expulsion edge.