Table 4.

Disc herniation and control groups

spinal level	Disc herniation		facet tropism		χ2	p
			YES	NO
L3–4	YES	8	2	6	0.238	0.625
	NO	78	14	64
L4–5	YES	44	19	25	10.448	0.001
	NO	42	5	37
L5-S1	YES	34	24	10	22.683	0.000
	NO	52	10	42