Table 2:

2 × 2 contingency table for a ruptured-versus-intact annulus as determined surgically and on imaging

Imaging Assessment	Surgical Assessment		Totals
	(Criterion Standard)
	Annulus Ruptured^{^a}	Intact Annulus^{^b}
Annulus ruptured^{^a}	37	9	41
Intact annulus^{^b}	4	4	13
Totals	46	8	54

↵a Extrusions and sequestrations.
↵b Protrusions only.