Klemt et al reported risk calculators for reinfection following revision surgery for periprosthetic joint infection. One calculator involves total knee arthroplasty (TKA). The authors are from Massachusetts General Hospital.
Patient selection: revision surgery for periprosthetic joint infection involving a TKA
Parameters:
(1) sex
(2) age in years
(3) body mass index in kg per square m
(4) extremity status (undefined; extremity status 3 presumably mean urgent or emergent)
(5) government insurance
(14) surgery
(15) number of prior open surgeries
(16) microbiology
|
Parameters |
Findings |
Points |
|
sex |
male |
14 |
|
|
female |
0 |
|
age in years |
<= 75 years |
0 |
|
|
> 75 years |
10 |
|
body mass index |
< 15 kg per sq meter |
19 |
|
|
15 to 40 kg per sq m |
0 |
|
|
> 40 kg per sq m |
25 |
|
extremity status |
1 or 2 |
0 |
|
|
3 |
31 |
|
government insurance |
no |
0 |
|
|
yes |
7 |
|
metastatic cancer |
no |
0 |
|
|
yes |
44 |
|
drug use |
no |
0 |
|
|
yes |
34 |
|
HIV/AIDS |
no |
0 |
|
|
yes |
27 |
|
renal failure |
no |
0 |
|
|
yes |
21 |
|
diabetes |
no |
0 |
|
|
yes |
14 |
|
depression |
no |
0 |
|
|
yes |
10 |
|
alcohol drinking |
no |
0 |
|
|
yes |
9 |
|
smoking |
no |
0 |
|
|
yes |
7 |
|
rheumatoid arthritis |
no |
0 |
|
|
yes |
7 |
|
surgery |
irrigation and debridement without modular component exchange during revision surgery |
62 |
|
|
irrigation and debridement with modular component exchange during revision surgery |
53 |
|
|
other (1 or stage revision, etc) |
0 |
|
number of prior open surgeries |
0 to 2 |
0 |
|
|
3 |
48 |
|
|
>= 4 |
56 |
|
microbiology |
Enterococcus |
25 |
|
|
other |
0 |
total score =
= SUM(points for all of the parameters)
Interpretation:
• minimum score:
• maximum score (all parameters): 403
• maximum score (without comorbidities): 230
• The higher the score the greater the risk of reinfection.
|
Total Score |
Risk |
|
0 |
0.35% |
|
10 |
0.73% |
|
20 |
0.98% |
|
30 |
1.4% |
|
40 |
2% |
|
50 |
2.6% |
|
60 |
3.7% |
|
70 |
4.9% |
|
80 |
5.5% |
|
90 |
7% |
|
100 |
8.6% |
|
110 |
11.8% |
|
120 |
13.6% |
|
130 |
16% |
|
140 |
18.5% |
|
150 |
20.6% |
|
160 |
23.5% |
|
170 |
27% |
|
180 |
30% |
Performance:
• The area under the ROC curve is 0.75.
Specialty: Infectious Diseases
