Grading system
| Points | ||
|---|---|---|
| Spacer margins | 0 | Any evidence of subsidence or lucency around the cage |
| 1 | Tightly marginated with both endplates without bone resorption or subsidence | |
| Bone within cage | 0 | Lucency within cage similar to nonossified disc |
| 1 | Increased density within spacer beyond that of nonossified disc space suggestive of trabecular bone | |
| Bone bridge | 0 | No bony bridging between endplates |
| between endplates | 1 | < 0.5 cm bridge on either sagittal or coronal reconstruction |
| 2 | ≥ 0.5 cm bridge on either sagittal or coronal reconstruction |
Maximum score = 4.