Table 4.

Clinical outcomes between in the two groups.

	Early (n = 25)	Late (n = 23)	P
VAS back pain
Pre-operative	5.80 ± 1.47	5.30 ± 1.58	.266∗
1 week	2.36 ± 0.71	2.61 ± 1.27	.436∗
1 year	1.72 ± 0.77	1.13 ± 0.87	.155∗
ANOVA			<.001†
VAS leg pain
Pre-operative	7.76 ± 1.20	7.39 ± 1.31	.313∗
1 week	2.44 ± 1.39	3.13 ± 2.11	.185∗
1 year	1.56 ± 0.69	1.30 ± 0.52	.585∗
ANOVA			<.001†
Odom's criteria (1 week)			.100‡
Excellent	16	10
Good	8	10
Fair	1	3
Poor	0	0
Odom's criteria (1 year)			.354‡
Excellent	18	18
Good	6	3
Fair	1	2
Poor	0	0

ANOVA = analysis of variance, VAS = visual analogue scale.

^∗Independent t test.

^†ANOVA.

^‡Pearson's chi square test.