Retention assemblies for intervertebral devices

A coupler (400) for providing connection between an intervertebral device (100) and a bone plate (300) comprising:

• the coupler (400) including an inner housing (410) sized to fit within a distal opening (116) provided in a base element (110) of the intervertebral implant, the inner housing (410) having a first lumen (410L1) extending therethrough, a second lumen (410L2), which is oriented substantially perpendicular to the first lumen (410L1), and positioned to intersect with the first lumen, one or more protrusion members (430) being positioned within the second lumen and constructed to translate within the second lumen (410L2), an elongate member (420) extends through the first lumen (410L1) to interact with the one or more protrusion members (430), wherein translation of the elongate member in a first direction causes perpendicular translation of the one or more protrusion members, causing the one or more protrusion members to extend beyond an outer perimeter of the inner housing (410) to engage an inner surface of the distal opening of the base element (110), providing multi-axial connection between the coupler (400) and the base element (110) of the intervertebral device (100), a plate assembly (300) being removably secured to a second end of the coupler.