Table 3 Logistic regression analysis of factor associated with SSI

Duration from trauma to surgery

≤ 8 days

1470 (75.1%)

15 (1.0%)

1455 (99.0%)

> 8 days

487 (24.9%)

29 (6.0%)

458 (94.0%)

6.1 (3.3, 11.6)

< 0.001

5.5 (2.9, 10.3)

5.22

< 0.001

Total

1957 (100%)

44 (2.2%)

1913 (97.8%)

Duration of hospitalisation

≤ 5 days

903 (41.3%)

10 (1.1%)

893 (98.9%)

> 5 days

1286 (58.7%)

50 (3.9%)

1236 (96.1%)

3.6 (1.8, 7.2)

< 0.001

2.7 (1.4, 5.5)

2.13

0.034

Total

2189 (100%)

60 (2.7%)

2129 (97.3%)

Duration of surgery

< 100 min

1218 (55.6%)

13 (1.0%)

1205 (99.0%)

≥ 100 min

971 (44.4%)

47 (4.8%)

924 (95.2%)

4.7 (2.5, 8.8)

< 0.001

2.8 (1.4,5.5)

2.96

0.003

Total

2189 (100%)

60 (2.7%)

2129 (97.3%)

Specialty

General

127 (5.8%)

3 (2.4%)

124 (97.6%)

Neuro

192 (8.8%)

10 (5.2%)

182 (94.8%)

2.3 (0.6, 8.1)

0.220

Orthopaedic

1870 (85.4%)

47 (2.5%)

1823 (97.5%)

1.1 (0.3, 3.5)

0.916

-

-

-

Total

2189 (100%)

60 (2.7%)

2129 (97.3%)

Type of injury

Non-trauma

232 (10.6%)

16 (6.9%)

216 (93.1%)

Trauma

1957 (89.4%)

44 (2.2%)

1913 (97.8%)

0.3 (0.2, 0.6)

< 0.001

-

-

-

Total

2189 (100%)

60 (2.7%)

2129 (97.3%)

Presence of implant

No

802 (36.6%)

14 (1.7%)

788 (98.3%)

Yes

1387 (63.4%)

46 (3.3%)

1341 (96.7%)

1.9 (1.1, 3.5)

0.033

Total

2189 (100%)

60 (2.7%)

2129 (97.3%)

Wound class

Clean wound

1329 (60.7%)

40 (3%)

1289 (97%)

Clean-contaminated wound

219 (10%)

14 (6.4%)

205 (93.6%)

2.2 (1.2, 4.1)

0.014

-

-

-

Contaminated

641 (29.3%)

6 (0.9%)

635 (99.1%)

0.3 (0.1, 0.7)

0.007

Total

2189 (100%)

60 (2.7%)

2129 (97.3%)