Table 2.
Patient and surgical characteristics
| Patients with SSI (n=46) | Cured (n=31) |
Relapse (n=6) |
Lost FU (n=9) |
||
|---|---|---|---|---|---|
| Medical conditions | |||||
| Male sex, n (%) | 28 (61) | 18 (58) | 5 (83) | 5 (56) | |
| Median age, years (IQR) | 55 (40-62) | 54 (44-62) | 44 (33-55) | 58 (39-73) | |
| Mean BMI kg/m2 (SD) | 27.2 (4.9) | 27.5 (5.3) | 27.9 (4.2) | 26 (4) | |
| Overweight (BMI>25kg/m2), n (%) | 29 (63) | 20 (58) | 5 (83) | 4 (44) | |
| Obesity (BMI>30kg/m2), n (%) | 12 (26) | 7 (23) | 3 (50) | 2 (22) | |
| Malnutrition (BMI<18kg/m2), n (%) | 2 (4) | 1 (3) | 0 | 0 | |
| Diabetes, n (%) | 7 (15) | 6 (19) | 0 | 1 (11) | |
| Immunodeficiency, n (%) | 2 (4) | 2 (6) | 0 | 0 | |
| Renal insufficiency, n (%) | 2 (4) | 1 (3) | 0 | 0 | |
| Liver insufficiency, n (%) | 0 | 0 | 0 | 0 | |
| Chronic pulmonary disease, n (%) | 7 (15) | 4 (19) | 1 (17) | 2 (22) | |
| Cardiac insufficiency, n (%) | 2 (4) | 1 (3) | 0 | 1 (11) | |
| Coronaropathy, n (%) | 2 (4) | 1 (3) | 0 | 1 (11) | |
| Active malignancy, n (%) | 5 (11) | 5 (16) | 0 | 0 | |
| Modified Charlson score, median (IQR) | 1 (0-3) | 1 (0-4) | 1 (0-1) | 1 (0-1) | |
| Active smoking, n (%) | 12 (26) | 8 (26) | 2 (33) | 2 (22) | |
| Alcohol abuse, n (%) | 2 (4) | 2 (6) | 0 | 0 | |
| Previous spine surgery, n (%) | 9 (20) | 5 (16) | 2 (33) | 2 (22) | |
| Previous SSI after spine surgery, n (%) | 3 (7) | 2 (6) | 1 (17) | 0 | |
| Operative features (index surgery) | |||||
| Degenerative, n (%) | 34 (74) | 23 (74) | 4 (67) | 7 (78) | |
| Traumatic, n (%) | 10 (22) | 6 (19) | 2 (33) | 2 (22) | |
| Malignancy, n (%) | 2 (4) | 2 (6) | 0 | 0 | |
| DL - post, n (%) | 35 (76) | 24 (77) | 4 (33) | 7 (78) | |
| DL - ant, n (%) | 0 | 0 | 0 | 0 | |
| DL - comb, n (%) | 9 (20) | 6 (19) | 2 (33) | 1 (11) | |
| Cerv - ant, n (%) | 0 | 0 | 0 | 0 | |
| Cerv - post, n (%) | 1 (2) | 1 (3) | 0 | 0 | |
| Cerv - comb, n (%) | 1 (2) | 0 | 0 | 1 (11) | |
| Antibiotic prophylaxis, type (n) | C (33); V (12) | C (23); V (8) | C (4); V (2) | C (6); V (2) | |
| Number of fused vertebrae, median (IQR) |
4 (3-6) | 4 (3-6) | 3 (2-5) | 6 (3-7) | |
| ≤ 4 fused vertebrae, n (%) | 26 (57) | 18 (58) | 4 (67) | 4 (44) | |
| > 5 fused vertebrae, n (%) | 20 (43) | 13 (42) | 2 (33) | 5 (56) | |
| Interbody cages, n (%) | 29 (63) | 19 (62) | 4 (67) | 6 (67) | |
| Bone graft, n (%) | 38 (83) | 27 (87) | 6 (100) | 5 (56) | |
| Mean operative time, hours (SD) | 195 (79) | 187 (81) | 230 (89) | 214 (58) | |
| Mean intraoperative blood loss, mL (SD) | 922 (741) | 934 (715) | 462 (398) | 1216 (1032) | |
FU: Follow-up; BMI: body mass index (kg/m2); DL: dorsal-lumbar; Cerv: cervical; post: posterior; ant: anterior; comb: combined (anterior-posterior approach). Antibiotic prophylaxis: C: cephalosporin; V: vancomycin.
No significant difference was found between cured and relapse groups for any characteristic.