A surgical implant for preventing withdrawal of a bone dowel graft from a facet joint, the apparatus including a plate having a posterior face and an anterior face, a passageway extending to and between the posterior face and the anterior face, an opening through the posterior face that is configured for detachably coupling to an inserter and one or more anti-migration projections extending outwardly from the anterior face. In use, the plate is placed over a bone dowel seated in a facet joint and coupled to the superior process and the inferior process by inserting a screw through the passageway into the inferior process.