Table 1 Demographic and preoperative characteristics of the patients receiving elective lumbar spinal fusion

Female^a

17 (81.0)

7 (53.8)

0.130

Age (years)

64.0 (11.1)

56.1 (15.0)

0.136

Smoking^a

4 (19.0)

3 (23.1)

1.000

Body mass index (kg/m²)

23.9 (3.5)

28.0 (6.9)

0.049

Bone mineral density (g/cm²)

0.8 (0.2)

0.8 (0.2)

0.242

T-score

-2.0 (1.3)

-1.2 (1.1)

0.079

Preoperative evaluation

 ODI

22.3 (9.8)

20.9 (6.3)

0.558

 VAS

7.2 (1.9)

6.2 (1.6)

0.135

 25(OH)VitD (ng/ml)

26.8 (8.8)

26.4 (12.9)

0.607

 Calcium (mg/dl)

8.9 (0.5)

8.7 (0.7)

0.424

Operation data

 Blood Loss (ml)

300.5 (290.3)

390.0 (288.2)

0.206

 Operation time (min)

166.2 (51.2)

195.8 (57.6)

0.106

 Number of fused vertebrae

2.3 (0.5)

2.8 (1.0)

0.248