Table 1 Demographic and clinical data of Patients (n = 113)

Male: female

1:0.89

Age, mean ± SD (range)

37.4 ± 7.8 (23–68 yr)

Height, mean ± SD (range)

169.7 ± 6.2 (155–183 cm)

Weight, mean ± SD (range)

67.4 ± 8.7 (47–90 kg)

BMI, mean ± SD (range)

17.9 ± 5.22 (12–35)

Operation time

209.0 ± 29.1(170-300 min)

Bleeding volume

276.1 ± 77.1(100-500 mL)

One vertebral level N (%)

100 (88.5%)

Two vertebral levels N (%)

13 (11.5%)

L2-L3 N (%)

13 (11.5%)

L3-L4 N (%)

29 (25.7%)

L4-L5 N (%)

54 (47.9%)

L5-S1 N (%)

17 (15.0%)