Table 2 Comparison of parameters between CS group and non-CS group

Age (years)

51.7 ± 10.5

50.5 ± 8.1

0.351

Gender (Male)

44 (53.7)

93 (47.2)

0.359

Smoking (n, %)

25 (30.5)

40 (20.3)

0.087

Diabetes (n, %)

12 (14.6)

23 (11.7)

0.552

Fusion level (n, %)

0.452

 L3/4

2 (2.4%)

6 (3.0%)

 L4/5

43 (52.4%)

118 (59.9%)

 L5/S1

37 (45.1%)

73 (37.1%)

Follow-up (month)

18 (14, 25)

18 (15, 24)

0.626

Blood loss (ml)

153.3 ± 46.7

149.2 ± 51.7

0.523

Operation time (min)

170.9 ± 31.4

177.4 ± 30.8

0.118

Use of allograft (n, %)

4 (4.8%)

16 (8.1)

0.339

BMI (Kg/m²)

24.9 ± 1.8

24.3 ± 1.5

0.02

BMD-l

−1.1 ± 0.8

−0.2 ± 1.1

< 0.01

BMD-f

−2.0 (−2.3, − 1.3)

− 0.6 (− 1.3, 0.5)

< 0.01

HUm

116.1 ± 16.6

146.0 ± 18.7

< 0.01

HU1

121.2 ± 17.3

149.7 ± 20.7

< 0.01

HU2

114.7 ± 17.3

143.5 ± 19.9

< 0.01

HU3

114.7 ± 19.1

145.3 ± 19.3

< 0.01

HU4

113.9 ± 18.2

145.8 ± 20.2

< 0.01

Cage height (mm)

0.534

 8

14 (17.1%)

30 (15.2%)

 10

56 (68.3%)

127 (64.5%)

 12

12 (14.6%)

40 (20.3%)

Preoperative Disc height (mm)

9.4 ± 0.8

9.6 ± 0.9

0.03

Postoperative Disc height (mm)

12.7 ± 0.9

12.6 ± 0.8

0.09

Follow-up Disc height (mm)

10.8 ± 0.8

11.4 ± 0.9

< 0.01

Modified Taillard index (%)

31.0 ± 4.9

32.5 ± 5.1

0.02

Fusion rate

85.4%

92.4%

0.07

Preoperative VAS of back

5.5 (5, 6)

5.0 (5, 7)

0.27

3 m postoperative VAS of back

2 (1, 3)

2 (1, 3)

0.30

Follow-up VAS of back

2 (1, 2)

2 (1, 2)

0.08

Preoperative VAS of leg

6 (5, 7)

6 (5, 7)

0.48

3 m postoperative VAS of leg

2 (2, 3)

2 (1, 2)

< 0.01

Follow-up VAS of leg

2 (1, 2)

2 (1, 2)

0.02

Preoperative ODI

58.5 ± 13.7

58.2 ± 12.3

0.84

3 m postoperative ODI

36.7 ± 9.7

34.4 ± 8.9

0.06

Follow-up ODI

24.6 ± 6.4

22.4 ± 7.7

0.02