Table 3 Binary logistic regression model for the development of ASSI after lumbar surgery

Patient-related risk factors

Age (year)

0.729(0.544–0.976)

0.34

Sex

0.000(0.000–2.294)

0.074

BMI (kg/m²)

2.888(1.059–7.875)

0.038

Smoking (year)

1.684(1.008–2.813)

0.047

Drink wine

2.180(0.241–9.771)

0.121

Academic career

3.337(0.012–9.383)

0.265

Diabetes mellitus

2.200(0.046–1.102)

0.020

COPD

0.000

0.987

Osteoporosis

1.842(0.151–4.836)

0.044

Nutritional status

0.000(0.000–162.412)

0.220

Fracture

2.916(0.156–5.308)

0.001

Hypertension

0.011(0.00–13.221)

0.213

Long-term use of hormone

0.551(0.151–4.836)

0.105

Procedure-related risk factors

Preoperative antibiotics

2.030(0.005–5.216)

0.025

Operative type

1.374(0.010–4.445)

0.035

Operative incision (cm)

1.027(0.555–1.899)

0.993

Operative time (min)

1.014(0.987–1.042)

0.030

Blood loss (ml)

1.022(0.999–1.045)

0.024

Number of internal fixation metals (piece)

22.589(0.891–572.990)

0.059

Intraoperative blood transfusion

0.000(0.000–0.417)

0.413

Drainage tube (root)

0.019(0.000–11.327)

0.225

Time of draining (day)

4.983(1.641–15.140)

0.033

Capacity draining (ml)

1.008(0.990–1.025)

0.392