Table 1.
Characteristics of 93 patients with spinal implant-associated infections
| Characteristic | All patients (n = 93) | Patients treated with biofilm-active antibiotics (n = 30) | Patients treated with biofilm-nonactive antibiotics (n = 63) | P value |
|---|---|---|---|---|
| Age, median (range)—years | 66 (11–85) | 68 (11–83) | 66 (18–85) | 0.822 |
| Female sex | 46 (49) | 13 (43) | 34 (54) | 0.380 |
| Body mass index, median (range), kg/m2 | 28.5 (14.6–38.1) | 28.3 (14.6–37.0) | 28.6 (18.7–38.1) | 0.714 |
| Body mass index ≥ 25 kg/m2 | 56 (60) | 15 (50) | 43 (68) | 0.523 |
| ASA, median (range) | 2 (1–4) | 3 (2–4) | 2 (1–4) | 0.425 |
| Comorbidities, median (range) | 2 (0–6) | 2 (0–6) | 1 (0–5) | 0.233 |
| Coexisting medical conditionsa | ||||
| Arterial hypertension | 51 (55) | 17 (57) | 34 (54) | 0.828 |
| Diabetes mellitus | 25 (27) | 12 (40) | 13 (21) | 0.078 |
| Active malignancy | 21 (23) | 8 (27) | 13 (21) | 0.598 |
| Rheumatic or other autoimmune disease | 13 (14) | 4 (13) | 9 (14) | 1.000 |
| Hypothyroidism | 10 (11) | 2 (7) | 8 (13) | 0.492 |
| Chronic renal failure | 9 (10) | 3 (10) | 6 (10) | 1.000 |
| Radiotherapy or chemotherapy | 7 (8) | 1 (3) | 6 (10) | 0.422 |
| Immunosuppression | 4 (4) | 1 (3) | 3 (5) | 1.000 |
| Liver cirrhosis | 3 (3) | 2 (7) | 1 (2) | 0.243 |
| Indication for primary spinal surgery | ||||
| Degenerative spinal disease | 45 (48) | 10 (33) | 35 (56) | 0.050 |
| Vertebral fracture | 20 (22) | 6 (20) | 14 (22) | 1.000 |
| Spinal tumor | 15 (16) | 5 (17) | 10 (16) | 1.000 |
| Vertebral osteomyelitis | 8 (9) | 6 (20) | 2 (3) | 0.013 |
| Congenital deformity | 5 (5) | 3 (10) | 2 (3) | 0.324 |
| Level of spine stabilizationb | ||||
| Cervical | 6 (6) | 2 (7) | 4 (6) | 1.000 |
| Thoracic | 35 (38) | 13 (43) | 22 (35) | 0.495 |
| Lumbosacral | 52 (56) | 15 (50) | 37 (59) | 0.510 |
| Stabilized segments, median (range) | 4 (1–17) | 5 (2–15) | 3 (2–17) | 0.106 |
Data are n. (%) of patients, unless otherwise indicated
ASA American Society of Anesthesiology
aDefinitions of coexisting medical conditions are summarized in Methods
bCategorized by the most superior segment involved