Table 5 Baseline features and postoperative outcomes of propensity matched analysis, BMI: Body Mass Index; ASA: American Society of Anesthesiologists, VAS: visual analogue scale [10]; ADL: Activity of Daily Living Scale [11], ODI: The Oswestry Disability Index [12], LOS: length of stay; EBL: estimate blood loss; USD: US dollar; SSI: surgical site infection, CSF: cerebrospinal fluid

Gender (male/female)

36/25

35/26

0.854

Age (year)

52.51 ± 13.59

54.10 ± 13.90

0.524

BMI (kg/m²)

22.75 ± 3.90

23.50 ± 4.04

0.303

ASA (1/2/3)

38/16/7

36/20/5

0.660

ODI (preop)

48.85 ± 8.34

48.85 ± 8.75

1

VAS (preop)

5.98 ± 1.44

6.01 ± 1.31

0.948

ADL (preop)

58.69 ± 7.07

58.11 ± 6.72

0.647

Comorbidity

 Hypertension

10

12

0.637

 Diabetes mellitus

5

4

1

 Heart disease

2

1

0.874

Preop hemoglobin (g/L)

134.08 ± 17.82

134.85 ± 19.32

0.819

Preop Albumin(g/L)

41.98 ± 4.00

41.33 ± 4.46

0.398

Disease

 spinal stenosis

37

39

0.709

 lumbar disc herniation

18

17

0.841

 lumbar instability

6

5

0.752

Surgical duration (min)

185.48 ± 51.36

185.27 ± 45.63

0.982

EBL (ml)

224.75 ± 124.16

191.23 ± 103.04

0.107

Wound length (cm)

9.00 ± 2.84

8.43 ± 2.44

0.234

Ambulatory interval (d)

2.67 ± 0.57

6.41 ± 3.49

0.0001

LOS (d)

8.95 ± 4.36

12.70 ± 6.13

0.0001

Total expenses [USD]

9409.39 ± 2812.55

10,481.33 ± 3049.43

0.048

Overall complications

2

8

0.048

Pneumonia

0

3

0.242

Reoperation

1

0

1

SSIs

1

3

0.611

CSF leakage

0

1

1

Urinary infection

0

1

1