Vertebral implants and attachment assemblies

A method of inserting a prosthetic implant, comprising the steps of:

• providing the prosthetic implant, wherein the prosthetic implant includes:
• a first body including a first plate with a plurality of spaced apart first legs extending from the first plate, at least two of the first legs defining inwardly extending first projections;
• a second body including a second plate with a plurality of spaced apart second legs extending from the second plate, one of the second legs being an expandable leg and wherein two edges of the expandable leg have second projections;
• wherein the first and second bodies are interdigitated such that the first legs extend into the spaces defined between the second legs and the second legs extend into the spaces defined between the first legs in an orientation wherein the second projections are aligned with the first projections;
• and
• a locking mechanism configured to engage the expandable leg and splay the outward edges outward such that the second projections engage and lock with the first projections;
• attaching the first body to the first vertebra;
• attaching the second body to the second vertebra;
• engaging the prosthetic implant with an implantation instrument;
• and
• distracting or compressing the first body and second body away from or toward one another using the implantation instrument to enable insertion of the prosthetic implant into a space between the first vertebra and the second vertebra.