When reporting bone grafts with spinal fusions (22548-22812) and/or instrumentation (22840-22855), you should choose from among the following five codes, depending on whether the surgeon harvested the graft from the patient's own body (autograft) or received the graft from a bone bank (allograft). Remember, a structural bone graft consists of a single piece of bone that provides direct support for skeletal structures, while a morselized (or small-segment) graft consists of small pieces of bone joined together to fill bony cavities, primarily to promote new bone growth.