Table I.
Clinical and laboratory characteristics of study subjects.
| Characteristic | Prosthetic joint infection (n = 49) | Noninfection (n = 21) | p-value |
|---|---|---|---|
| Mean age, yrs (SD) | 66.0 (13.8) | 64.9 (12.2) | 0.739* |
| Sex, n (%) | 0.156† | ||
| Male | 30 (61.2) | 9 (42.9) | |
| Female | 19 (39.8) | 12 (57.1) | |
| Site of arthroplasty, n (%) | 0.676† | ||
| Knee | 26 (53.1) | 10 (47.6) | |
| Hip | 23 (46.9) | 11 (52.4) | |
| Mean body mass index, kg/m2 (SD) | 27.6 (4.8) | 28.3 (4.8) | 0.537* |
| Surgical procedure, n (%) | 0.525† | ||
| Debridement with implant retention | 12 (24.5) | 3 (14.3) | |
| Revision with implant resection | 37(75.5) | 18 (85.7) | |
| Antibiotics received two weeks prior to surgery, n (%) | 18 (36.7) | 4 (19.0) | 0.144† |
| Clinical and laboratory findings | |||
| Presence of sinus tract, n (%) | 12 (22.6) | 0 (0.0) | < 0.001† |
| Positive synovial fluid,≥ two periprosthetic tissue cultures, n (%) | 36 (73.5) | 1 (4.8) | < 0.001† |
| Mean synovial fluid white blood-cell count, cells/ml (SD) | 58,780.8 (101176.1) | 906.5 (548.3) | 0.011‡ |
| Mean synovial fluid polymorphonuclear neutrophils, % (SD) | 79.7 (13.0) | 44.4 (17.0) | < 0.001‡ |
| Mean serum CRP, mg/l (SD) | 47.4 (41.4) | 9.6 (7.1) | < 0.001‡ |
| Mean serum ESR, mm/hr (SD) | 67.6 (34.2) | 13.5 (5.6) | < 0.001‡ |
| Acute inflammation in periprosthetic tissue histopathology, n (%) | 24 (75.0) | 0 (0) | < 0.001† |
*
Independent-samples t-test.
†
Chi-squared test.
‡
Mann-Whitney U test.