Table 2 Evaluation criteria of bone fusion

A

Definitive fusion: definitive bony trabecular briding across the graft interface, no motion on flexion–extension X-ray films, and no gap at the interface

B

Probable fusion: no definitive bony trabecular crossing, but no detectable motion and no identifiable gap at the interface

C

Possible pseudarthrosis: no bony trabecular crossing, no motion, but identifiable gap at the interface

D

Definite pseudarthrosis: no traversing trabecular bone, definitive gap, and motion greater than 3°