Table 3.

Outcomes of intervertebral disc height and the Pfirrmann grade 18 months after treatment in two groups

	The treatment group, n = 50	The control group, n = 48	P value
Intervertebral disc height
Before treatment	10.50 ± 0.91	10.41 ± 0.78	0.771
Final follow-up	10.25 ± 0.81	9.32 ± 0.85	0.042
The Pfirrmann grade
Before treatment			0.169
I	0	0
II	2	4
III	31	32
IV	17	8
Final follow-up			0.049
I	0	0
II	1	1
III	30	17
IV	19	30