Table 4.

Comparison between the ISI and non-ISI group in patients > 65 years old.

	ISI (N = 33)	Non-ISI (N = 56)	P-value
Age, yrs	72.91 ± 4.69	74.46 ± 5.22	0.08
Sex
Men	23 (69.7%)	24 (42.9%)	0.01a
Women	10 (30.3%)	32 (57.1%)
PM grade 3
Chondrocyte proliferation
C1	0 (0.0%)	0 (0.0%)	0.34
C2	2 (66.7%)	2 (33.3%)
C3	1 (33.3%)	4 (66.7%)
Granular matrix change
M1	0 (0.0%)	2 (33.3%)	0.50
M2	3 (100.0%)	4 (66.7%)
PM grade 4, 5
Chondrocyte proliferation
C1	3 (10.0%)	3 (6.0%)	0.46
C2	8 (26.7%)	12 (24.0%)
C3	19 (63.3%)	35 (70.0%)
Granular matrix change
M1	2 (6.7%)	8 (16.0%)	0.31
M2	28 (93.3%)	42 (84.0%)

Values are presented as number (%), or mean ± standard deviation unless otherwise indicated.

ISI, intradiscal steroid injection; PM, pfirrmann.

Continuous variables were analyzed using student's t-test.

Categorical variables were analyzed using the Cochran-Armitage trend test and Fisher's exact test.

^aP-value < 0.05.