Table 3 Baseline characteristics of patients in each group

Age (year)

68.8 ± 3.99

68.2 ± 4.54

72.0 ± 5.29

0.065

Sex (female/male)

32:3

38:0

29:0

0.318

BMI (kg/m²)

23.49 ± 3.12

23.48 ± 2.19

22.04 ± 3.51

0.229

BMD (L1-4, T-score)

-1.02 ± 1.69

-1.25 ± 1.27

-1.87 ± 0.58

0.038*

Preop. diagnosis

LDK

2

4

4

0.762

Combined state

Spinal stenosis

24 (68.6%)

15 (39.5%)

10 (34.5%)

0.034*

Spondylolisthesis

1 (2.9%)

1 (2.6%)

2 (6.9%)

0.675

Old vertebral column fracture

8 (8.6%)

11 (28.9%)

18 (62.1%)

0.025*

Scoliosis

4 (11.4%)

6 (15.8%)

5 (17.2%)

0.714

Previous surgery

2 (5.7%)

2 (5.3%)

4 (13.8%)

0.383

No. of comorbidities

HTN

14 (40%)

12 (31.6%)

12 (41.4%)

0.726

Angina

0 (0%)

2 (5.3%)

4 (13.8%)

0.463

DM

2 (5.7%)

2 (5.3%)

6 (20.9%)

0.154

CKD

2 (5.7%)

0 (0%)

1 (3.4%)

0.051

Old CVA

2 (5.7%)

2 (5.3%)

0 (0%)

0.512

RA

1 (2.9%)

0 (0%)

2 (6.9%)

0.481

Parkinson’s disease

0 (0%)

2 (5.3%)

0 (0%)

0.714

COPD

0 (0%)

0 (0%)

2 (6.9%)

0.081

UIV (n, %)

 ≥ T10

28 (80%)

36 (94.7%)

29 (100%)

0.043*

 ≤ T11

7 (20%)

2 (5.3%)

0 (0%)

LIV (n, %)

S1

35 (100%)

38 (100%)

29 (100%)

Operation time (min)

342.2 ± 54.7

351.6 ± 61.5

392.3 ± 57.2

0.041*

Blood loss (ml)

2213.33 ± 760.51

2253.33 ± 777.24

2526.67 ± 924.32

0.035*