Table 1 Univariate analyses of factors associated with time to recurrent infection
Variable | Category/term | No. of infection recurrence/total | Hazard ratio (95% CI) | P value |
|---|---|---|---|---|
Age (**) | – | – | 1.01 (1.00 – 1.02) | 0.204 |
Gender | Female | 30/48 | 1 | 0.348 |
Male | 53/82 | 1.24 (0.79 – 195) | ||
BMI (*) | – | – | 0.99 (0.95 – 1.02) | 0.437 |
Charlson score | 0 | 42/61 | 1 | 0.482 |
1 – 2 | 26/46 | 0.74 (0.45 – 1.21) | ||
3 + | 15/23 | 0.88 (0.49 – 1.59) | ||
Tumour type | Osteosarcoma | 46/65 | 1 | 0.434 |
Chondrosarcoma | 20/30 | 1.10 (0.65 – 1.86) | ||
Ewing’s sarcoma | 3/5 | 0.82 90.26 – 2.64) | ||
Giant cell tumour of bone | 5/9 | 0.59 (0.23- 1.49) | ||
Metastatic bone disease | 4/9 | 0.63 (0.23 – 1.75) | ||
Spindle cell sarcoma | ¾ | 1.28 (0.40 – 4.14) | ||
Other sarcomas | 2/8 | 0.34 (0.08 – 1.39) | ||
Type of prostheses | Distal femoral replacement | 28/46 | 1 | 0.237 |
Proximal tibial replacement | 26/31 | 1.32 (0.81 – 2.18) | ||
Proximal femoral replacement | 10/21 | 0.65 (0.33 – 1.25) | ||
Hemipelvic reconstruction | 4/8 | 1.03 (0.40 – 2.64) | ||
Total femoral replacement | 6/7 | 1.11 (0.40 – 2.64) | ||
Diaphyseal femoral replacement | 2/6 | 0.42 (0.12 – 1.50) | ||
Distal humeral replacement | ¾ | 1.79 (0.61 – 5.19) | ||
Proximal humeral replacement | 3/5 | 2.14 (0.97 – 4.75) | ||
Total radial replacement | 1/2 | 0.85 (0.52 – 1.40) | ||
Prior revisions | 0 | 52/90 | 1 | 0.01 |
1 | 19/27 | 1.30 (0.77 – 2.19) | ||
2 or more | 12/13 | 2.64 (1.39 – 5.01) | ||
Local status | Uncompromised | 16/33 | 1 | 0.008 |
Compromised | 43/69 | 1.58 (0.89 – 2.82) | ||
Significantly compromised | 24/28 | 2.74 (1.44 – 5.23) | ||
Radiotherapy | No | 65/101 | 1 | 0.877 |
Yes | 18/29 | 1.04 (0.61–1.76) | ||
Chemotherapy within 3 months | No | 72/107 | 1 | 0.283 |
Yes | 11/23 | 0.71 (0.37 – 1.33) | ||
Type of surgery | Two-stage exchange (complete) | 13/29 | 1 | 0.002 |
Two-stage exchange (without reimplantation) | 9/17 | 1.74 (0.74 0 4.06) | ||
One-stage exchange | 7/11 | 1.87 (0.74 – 4.71) | ||
DAIR with an exchange of modular components | 20/33 | 2.23 (1.11 – 4.51) | ||
DAIR without exchange of modular components | 34/40 | 3.70 (1.93 – 7.10) | ||
Excision arthroplasty (+) | 0/3 | |||
Silver coated implant | No | 12/25 | 1 | 0.684 |
Yes | 17/32 | 1.17 (0.56 – 2.44) | ||
Organisms | Coagulase-negative staphylococci | 21/41 | 1 | 0.007 |
Staphylococcus aureus | 32/41 | 1.38 (0.92—2.05) | ||
Streptococcus spp. | 5/10 | 0.64 (0.31 – 1.34) | ||
Enterococcus spp. | 6/6 | 3.19 (1.51 – 6.74) | ||
Gram-negatives | 8/11 | 1.39 (0.73 – 2.67) | ||
Polymicrobial | 5/11 | 0.61 (0.28 – 1.35) | ||
No cultured organism | 6/10 | 0.66 (0.42 – 1.04) |