Table 1.
Primary and revision model inputs for hip and knee arthroplasty
| Age Cohort | Gender | Primary Arthroplasty Rate* | Primary SSI Rate** | Revision Arthroplasty Rate* | Revision SSI Rate** |
|---|---|---|---|---|---|
| Hip Arthroplasty | |||||
| 18–44 | Male | 0.02% | 0.52% | 2%/1.5%/1% | 2.03% |
| 45–64 | Male | 0.19% | 0.54% | 2%/1.5%/1% | 2.05% |
| 65–85 | Male | 0.46% | 0.58% | 2%/1.5%/1% | 1.79% |
| 85+ | Male | 0.76% | 0.63% | 2%/1.5%/1% | 1.85% |
| 18–44 | Female | 0.01% | 0.61% | 2%/1.5%/1% | 1.83% |
| 45–64 | Female | 0.18% | 0.56% | 2%/1.5%/1% | 2.05% |
| 65–85 | Female | 0.64% | 0.50% | 2%/1.5%/1% | 1.63% |
| 85+ | Female | 1.02% | 0.56% | 2%/1.5%/1% | 1.42% |
| Knee Arthroplasty | |||||
| 18–44 | Male | 0.01% | 0.66% | 2%/1.5%/1% | 2.26% |
| 45–64 | Male | 0.26% | 0.44% | 2%/1.5%/1% | 1.55% |
| 65–85 | Male | 0.76% | 0.35% | 2%/1.5%/1% | 1.28% |
| 85+ | Male | 0.28% | 0.45% | 2%/1.5%/1% | 0.88% |
| 18–44 | Female | 0.01% | 0.37% | 2%/1.5%/1% | 0.72% |
| 45–64 | Female | 0.39% | 0.29% | 2%/1.5%/1% | 1.12% |
| 65–85 | Female | 1.07% | 0.22% | 2%/1.5%/1% | 0.92% |
| 85+ | Female | 0.26% | 0.22% | 2%/1.5%/1% | 0.84% |
*
Primary arthroplasty rates were obtained using the 2012–2014 National Inpatient Sample
**
Primary and revision SSI rates were obtained from the 2012–2015 National Healthcare Safety Network
***
Revision arthroplasty rates were obtained from Katz et al.22 Rates were dependent on the time following a primary arthroplasty so we applied different rates to patients one year following an arthroplasty, two years following an arthroplasty, and then all subsequent years following an arthroplasty