Table 3 Clinical and microbiological factors associated with complete healing on bivariate analyses

Age, years; median (IQR)

62 (53–73)

60.5

62

0.33

Sex: male, n; (%)

114 (79.2)

62

44

0.49

Type 2 Diabetes, n; (%)

133 (92.4)

74

49

0.24

Cohort recruited in 2019, n; (%)

97 (67.4)

52/28

36/14

0.40

HbA1c, %; median (IQR)

8.9 (7.6–10.9)

8.7

9.1

0.44

Chronic kidney disease stage, n; (%)

 0

71 (49.3)

41

23

 1

2 (1.4)

1

1

 2

17 (11.8)

10

6

 3

33 (22.9)

18

12

 4

15 (10.4)

7

5

 5

6 (3.5)

3

3

Haemodialysis, n; (%)

3 (2.1)

1

2

0.31

Charcot neuroarthropathy (acute or chronic), n; (%)

10 (6.9)

6/74

4/46

0.91

IDSA/IWGDF Infection Score on admission (IQR)

3 (3–4)

3

3

0.64

Amputation characteristics

 Amputation of first ray (hallux), n; (%)

47 (32.6)

26

16

0.95

 Amputation of fifth ray, n; (%)

53 (36.8)

26/54

25/25

0.05

Most proximal amputation, n; (%)

 Transphalangeal

48 (33.3)

30

13

 Transmetatarsal

96 (66.7)

50

37

Amputation of > 1 ray, n; (%)

37 (25.7)

19

15

0.43

Angioplasty during admission, n; (%)

24 (16.7)

9/71

12/38

0.05

Microbiology

Superficial swabs sent for culture

118 (81.9)

70

35

0.01

Culture results from superficial swab, n (%)

 No growth

28 (19.4)

17

10

 Monomicrobial

65 (45.1)

39

17

 Polymicrobial

25 (17.4)

14

8

Time between swab and amputation, days; median (IQR)

3 (1–4)

3

3

0.98

Marginal bone sample sent for culture, n; (%)

131 (91%)

73

46

0.88

Culture results from marginal bone sample, n; (%)

 No growth

42 (29.2)

24

14

 Monomicrobial

51 (35.4)

28

18

 Polymicrobial

38 (36.4)

21

14

Planned antibiotic duration post amputation, weeks; median (IQR)

2 (2–4)

2

3.5

0.06

Outcome within 6 months

Further surgery, n; (%)

35 (26.7) of 131

8/71

24/24

< 0.0001