Table 2 Univariate analysis of variables between infection and non-infection group after PSM
Variable | Infection group (n = 70) | Non-infection group (n = 140) | P |
|---|---|---|---|
Obesity | 16 (22.9) | 18 (12.9) | 0.064 |
Dislocation | 7 (10.0) | 15 (10.7) | 0.873 |
Hypertension | 15 (10.7) | 11 (15.7) | 0.300 |
Diabetes | 24 (17.1) | 11 (15.7) | 0.793 |
Cerebrovascular disease | 9 (6.4) | 5 (7.1) | 0.845 |
Heart disease | 5 (3.6) | 3 (4.3) | 0.799 |
Liver disease | 2 (1.4) | 2 (2.9) | 0.475 |
Renal disease | 0 | 1 (1.4) | 0.156 |
History of any surgery | 22 (31.4) | 22 (15.7) | 0.008 |
Interval from injury to operation (days) | 7.3 ± 5.4 | 5.9 ± 3.1 | 0.016 |
4–10 | 33 (47.1) | 105 (75.0) | < 0.001 |
< 4 | 12 (17.1) | 10 (7.1) | |
> 10 | 25 (35.7) | 25 (17.9) | |
Surgical wound classification | |||
Type I (clean) | 62 (74.3) | 132 (94.3) | < 0.001 |
Type II (clean–contaminated) | 18 (25.7) | 8 (5.7) | |
Anesthesia pattern | 0.110 | ||
Regional | 52 (74.3) | 117 (83.6) | |
General | 18 (25.7) | 23 (16.4) | |
Injury mechanism | 0.076 | ||
Low to medium energy | 13 (18.6) | 42 (30.0) | |
High energy | 57 (81.4) | 98 (70.0) | |
Fracture type based on AO classification system | 0.990 | ||
44A | 21 (30.0) | 39 (28.1) | |
44B | 10 (14.3) | 25 (18.0) | |
44C | 7 (10.0) | 12 (8.6) | |
81A | 1 (1.4) | 1 (0.7) | |
81B | 2 (2.9) | 4 (2.9) | |
81C | 2 (2.9) | 5 (3.6) | |
82B | 10 (14.3) | 16 (11.5) | |
82C | 17 (24.3) | 37 (26.6) | |
Current smoking | 21 (30.0) | 23 (16.4) | 0.023 |
Alcohol drinking | 39 (55.7) | 57 (40.7) | 0.040 |
Reduction method | 0.868 | ||
Closed | 7 (10.0) | 13 (9.3) | |
Open | 63 (90.0) | 127 (90.7) | |
Internal fixation hardware | 0.579 | ||
Plate/screw | 55 (78.6) | 104 (74.3) | |
Screw only | 11 (15.7) | 30 (21.4) | |
Others | 4 (5.7) | 6 (4.3) | |
Bone grafting | 0.474 | ||
Yes | 7 (10.0) | 10 (7.1) | |
No | 63 (90.0) | 130 (92.9) | |
Surgical duration (minutes) | 143.4 ± 64.0 | 137.1 ± 62.1 | 0.495 |
≥ 180 min | 21 (30.0) | 29 (20.7) | 0.136 |
Intraoperative blood loss (ml) | 214.4 ± 272.0 | 178.4 ± 261.5 | 0.354 |
≥ 300 ml | 17 (24.3) | 23 (16.4) | 0.172 |
ASA classification | 0.315 | ||
I | 11 (15.7) | 27 (19.3) | |
II | 49 (70.0) | 102 (72.9) | |
III–IV | 10 (14.3) | 11 (7.9) | |
Allogeneic transfusion | 2 (1.4) | 4 (5.7) | 0.079 |
BMI (kg/m2) | 26.1 ± 4.1 | 25.8 ± 3.8 | 0.639 |
Obesity (BMI ≥ 30) | 16 (22.9) | 18 (12.9) | 0.064 |
Albumin (g/L) | 39.6 ± 7.5 | 40.9 ± 4.8 | 0.141 |
< 35 | 13 (18.6) | 14 (10.0) | 0.080 |
FBG (mmol/L) | 5.9 ± 2.1 | 5.8 ± 1.4 | 0.620 |
≥ 6.1 | 16 (22.9) | 39 (27.9) | 0.437 |
RBC (*1012/L) | 4.1 ± 0.7 | 4.3 ± 0.6 | 0.047 |
< Lower limit | 25 (35.7) | 31 (22.1) | 0.036 |
Hemoglobin (g/L) | 124.5 ± 22.6 | 133.6 ± 18.5 | 0.002 |
< Lower limit | 23 (32.9) | 20 (14.3) | 0.002 |
Hematocrit (%) | 36.8 ± 6.5 | 39.5 ± 5.3 | 0.002 |
< Lower limit | 44 (62.9) | 61 (43.6) | 0.008 |
Platelet count (*109/L) | 251.2 ± 117.3 | 238.3 ± 76.4 | 0.344 |
> 300 | 14 (20.0) | 21 (15.0) | 0.359 |
Plateletcrit (%) | 0.21 ± 0.11 | 0.19 ± 0.06 | 0.168 |
< 0.16 | 18 (25.7) | 29 (20.7) | 0.413 |
WBC count (*109/L) | 9.0 ± 2.6 | 8.9 ± 3.0 | 0.795 |
> 10 | 23 (32.9) | 43 (30.7) | 0.753 |
Neutrophil count (*109/L) | 6.4 ± 2.3 | 6.5 ± 2.9 | 0.975 |
> 6.3 | 23 (41.4) | 64 (45.7) | 0.556 |
Lymphocyte count (*109/L) | 1.6 ± 0.6 | 1.6 ± 0.8 | 0.658 |
< 1.1 | 15 (21.4) | 28 (20.0) | 0.809 |