Table 1.
Characteristics of 135 study patients with aseptic failure and prosthetic joint infectiona
| Parameter | Aseptic failure (n = 100) | Prosthetic joint infection (n = 35) | P value |
|---|---|---|---|
| Median patient age in yr (range) | 73 (27–89) | 73 (48–87) | 0.878 |
| Male patients | 36 (36) | 15 (43) | 0.545 |
| Type of joint prosthesis | |||
| Knee (n = 73) | 60 (60) | 25 (71) | 0.310 |
| Hip (n = 31) | 36 (36) | 5 (14) | 0.019 |
| Shoulder (n = 4) | 2 (2) | 3 (9) | 0.110 |
| Elbow (n = 4) | 2 (2) | 2 (6) | 0.276 |
| Type of revision surgery | |||
| Debridement and prosthesis retentionb | 0 | 14 (40) | <0.001 |
| One-stage exchange | 98 (98) | 1 (3) | <0.001 |
| Two-stage exchangec | 2 (2) | 20 (57) | <0.001 |
| Clinical signs of infection | |||
| Sinus tract | 0 | 7 (20) | <0.001 |
| Visible pus surrounding the prosthesis | 0 | 25 (71) | <0.001 |
| Mean synovial fluid cell countd | |||
| Leukocyte count in g/liter (range) | 0.3 (0.06–0.8) | 45 (1.4–76) | 0.005 |
| % neutrophils (range) | 19 (2–44) | 90 (54–98) | 0.017 |
| Received previous antibiotics | 0 | 23 (66) | <0.001 |
a
Values represent numbers (%) where not indicated otherwise. ND, not determined. Boldface P values represent significant values.
b
The polyethylene inlay and removable metal parts (i.e., femur head), where applicable, were investigated by a vortexing or sonication procedure.
c
The mean interval between explantation and reimplantation of the prosthesis was 118 days (range, 19 to 357 days).
d
Synovial fluid was available for 15 patients (11%).