A spacer formed of an intermetallic compound, such as nitinol. The spacer includes two segments shaped in opposing arches. The unique properties of the intermetallic compound enable the material to be deformed into a planar, insertable shape when the material is cooled below a transition temperature and returns to the undeformed shape when the material returns to an ambient, operational temperature. An expansion mechanism assembly can engage with the spacer to apply an expansion force. The expansion force extends the spacer longitudinally drawing the spacer into the planar configuration. The expansion mechanism assembly can be used to guide the spacer into the desired position within the patient. The spacer control mechanism assembly is subsequently removed, relieving the expansion force. The spacer returns to the natural undeformed shape as it returns to body temperature. Retention features can be integrated in the spacer to aid in retaining the spacer in location.
