Grade | Definition | N (%) |
1 | Absent bridging bone/fusion mass | 0 (0%) |
2 | Bone growth present without definitive bridging | 1 (5.6%) |
3 | Definitive bridging bone across sacroiliac joint | 1 (88.9%) |
NA | - | 1 (5.6%) |
Abbreviations: CT, computed tomography; NA, not available.