Table 1 Clinical factors associated with surgical site infection rate

Sex

Male

132(91.0)

13 (9.0)

145 (100.0)

3.430

0.094

Female

50 (82.0)

11(18.0)

61 (100.0)

Age group

≤ 19

8(100.0)

0 (0.0)

8 (100.0)

3.280

0.773

20–29

42 (87.5)

6(12.5)

48 (100.0)

30–39

38 (88.4)

5 (11.6)

43 (100.0)

40–49

30 (90.9)

3 (9.1)

33 (100.0)

50–59

33 (82.5)

7 (17.5)

40 (100.0)

60–69

19 (84.4)

3 (13.6)

22(100.0)

≥ 70

12(100.0)

0(0.0)

12 (100.0)

Spinal pathology/surgical indications

Trauma

96(90.6)

10(9.4)

106(100.0)

10.785

0.042*

Spondylosis

54 (80.6)

13(19.4)

67 (100.0)

Spinal tumour

21 (100.0)

0 (0.0)

21 (100.0)

Tuberculous spondilitis

9 (100.0)

0 (0.0)

9 (100.0)

Bacterial spondylitis

1 (50.0)

1 (50.0)

2 (100.0)

Syringomyelia

1 (100.0)

0 (0.0)

1 (100.0)

Cigarette smoking

No

172 (88.7)

22 (11.3)

194 (100.0)

0.311

0.419

Yes

10 (83.3)

2 (16.7)

12 (100.0)

Immunosuppression

No

172 (88.7)

22 (11.3)

194 (100.0)

0.311

0.419

Yes

10 (83.3)

2 (16.7)

12 (100.0)

Previous spine surgery

No

157 (87.7)

22 (12.3)

179 (100.0)

0.389

0.410

Yes

25 (92.6)

2 (7.4)

27 (100.0)

Number of Spine level Operated

One level

81 (90.0)

9 (10.0)

90 (100.0)

5.736

0.180

Two levels

59 (90.8)

6 (9.2)

65 (100.0)

Three levels

8 (66.7)

4(33.3)

12 (100.0)

Four levels

24 (88.9)

3 (11.1)

27 (100.0)

Five levels

10 (83.3)

2 (16.7)

12 (100.0)

Spine segment operated

Subaxial cervical spine

83 (95.4)

4 (4.6)

87 (100.0)

10.897

0.009*

Thoracic spine

23 (92.0)

2 (8.0)

25 (100.0)

Thoraco-lumbar Junction

27 (87.1)

4 (12.9)

31 (100.0)

lumbar

49 (77.8)

14 (22.2

63 (100.0)

Surgical approach to the spine

Anterior

71 (94.7)

4 (5.3)

75 (100.0)

5.013

0.082

Posterior

108 (84.4)

20 (15.6)

128 (100.0)

Anterior and posterior (combine)

3 (100.0)

0 (0.0)

3 (100.0)

Spine instrumentation

No

49 (83.1)

10 (16.9)

59 (100.0)

2.255

0.106

Yes

133 (90.5)

14 (9.5)

147 (100.0)

Duration of surgery

≤ 2 h

29 (100.0)

0 (0.0)

29 (100.0)

4.300

0.051

> 2 h

153 (86.4)

24 (13.6)

177 (100.0)

Total

182 (88.3)

24 (11.7)

206 (100.0)