Table 1. Anatomical measurements of the different parameters of the vertebral artery in relation to the axis vertebra.

r: right, l: left

VAX-1: Preosseous length of the vertebral artery (VA) segment related to the axis

VAX-2: Osseous + post-osseous length

dgen1: Distance of genu from the midline of the vertebral body

dgen2: Distance of genu from the superior articular facet (SAF)

tsaf: Transverse diameter of the SAF

occsaf: Occupancy of the SAF by VA

pertrocc: Percentage of occupancy of the SAF by VA

anggen: Angle of genu

VXA-1r	VXA-1l	VAX-2r	VAX-2l	dgen1r	dgen1l	dgen2r	dgen2l	tsafr	tsafl	occsafr	occsafl	pertroccr	pertroccl	anggenr	anggenl
	10	10	10	10	10	10	10	10	10	10	10	10	10	10	10
Mean 7.48	6.94	17.9	15.6	15.6	17.5	7.33	7.14	17.7	17.0	8.89	10.3	0.492	53.4	87.4	91.4
Median 6.21	6.47	17.3	16.4	15.9	17.6	7.10	6.30	18.1	17.8	9.25	10.9	0.523	56.3	85.0	88.0
Standard 3.88	2.01	7.84	4.53	1.22	2.07	2.15	2.31	1.31	1.63	2.25	3.55	0.123	10.8	17.5	13.0
Minimum 3.80	4.46	6.82	7.30	13.5	14.5	4.80	5.20	15.3	14.1	5.00	6.50	0.289	37.0	65	70
Maximum 14.5	10.5	31.0	20.0	17.4	21.0	10.1	11.5	19.5	18.5	11.8	18.5	0.677	65.7	115	110