Table 1.

Significant predictor variables for development new SIJ ankylosis

	β coefficient	SE	t	P value

2-year change in SSS backfill score	−0.18	0.049	−3.59	0.0005
2-year change in SSS erosion score	−0.20	0.05	−4.04	0.0001
2-year change in SSS fat score	0.23	0.06	3.57	0.0005