Table 1 Ultrasonographic measurements of the vertebral canal at the atlanto-occipital space in euthanased cattle of group A (mm, mean ± standard deviation, median, range)

Distance between skin and arachnoidea

38.6 ± 4

39.5 ± 4.2

(30 – 52)

(32 – 52)

n = 68^a

n = 73

Depth of the subarachnoid space dorsal to the spinal cord

8.9 ± 1.6

9.2 ± 1.6

(5 – 12)

(6 – 13)

n = 67^b

n = 73

Diameter of spinal cord

9.9 ± 1.2

10.1

(6 – 13)

(8 – 15)

n = 67^b

n = 72^b

Depth of the subarachnoid space ventral to the spinal cord

8.4

8.8 ± 1.8

(4 – 11)

(5 – 14)

n = 68

n = 73

Diameter of entire dural sac

26.9 ± 3

28.2 ± 3.5

(20 – 34)

(21 – 40)

n = 68

n = 73

Length of visible spinal cord

43.1 ± 10.3

(19 – 72)

-

n = 67^b