Table 2.
Univariate analysis of data collected from patients with a history of PJI after their initial arthroplasty
| Factors | No secondary PJI (n = 80/90) | Secondary PJI (n = 10/90) | Mean/percent difference | p value | |
|---|---|---|---|---|---|
| Age (years) (mean ± SD) | 61 ± 11 | 59 ± 12 | 2.2 | 0.623 | |
| Female sex (%) | 40/80 (50%) | 9/10 (90%) | OR = 8.83 | (95% CI, 1.13–403.33) | 0.02* |
| Body mass index (kg/m2) (mean ± SD) | 32 ± 7 | 34 ± 6 | 1.9 | 0.402 | |
| Diabetes (%) | 14% | 20% | 6% | 0.622 | |
| American Society of Anesthesiologists | 0.093 | ||||
| 1 | 1 | 0 | |||
| 2 | 28 | 0 | |||
| 3 | 32 | 7 | |||
| 4 | 0 | 0 | |||
| Charlson Comorbidity Index (mean ± SD) | 4 ± 1 | 3 ± 1 | 0.2 | 0.604 | |
| Time from diagnosis of initial PJI to second arthroplasty (months) (mean ± SD) | 35 ± 33 | 22 ± 23 | 13 months | 0.218 | |
| Treatment of initial PJI with I&D | 19% (n = 15) |
20% (n = 2) |
1% | 0.640 (all treatments compared) |
|
| Treatment of initial PJI with single-stage exchange | 11% (n = 9) |
10% (n = 1) |
1 | 0.640 (all treatments compared) |
|
| Treatment of initial PJI with two-stage exchange | 56% (n = 45) |
70% (n = 7) |
14% | 0.640 (all treatments compared) |
|
| Treatment of initial PJI with more than one technique | 14% (n = 11) |
0% (n = 0) |
14% | 0.640 (all treatments compared) |
|
| Patients treated with chronic suppressive antibiotics before second arthroplasty | 0% (n = 0) |
0% (n = 0) |
0% | 1.00 | |
| Initial infecting organism (staphylococcus species) | 35% (n = 28) |
70% (n = 7) |
OR = 4.26 | (95% CI, 0.89–27.50) | 0.032* |
| Initial infecting organism (resistant staphylococcus species) | 15% (n = 12) |
20% (n = 2) |
5.0% | 0.681 | |
| Second PJI infecting organism (staphylococcus species) | N/A | 80% (n = 8) |
N/A | N/A | |
| Second infecting organism (resistant staphylococcus species) | N/A | 10% (n = 1) |
N/A | N/A | |
| Initial and subsequent PJI on ipsilateral limb | N/A | 0% (n = 0) |
N/A | N/A | |
| Date of initial PJI (> year 2000) | 898% (n = 71) |
100% (n = 10) |
11.2% | 0.590 | |
* Significant; PJI = periprosthetic joint infection; I&D = irrigation and débridement; OR = odds ratio; CI = confidence interval; N/A = not applicable.