| very rarely | 11 | degree |
| to drain the infected site | 3 | purpose |
| to fuse the joint | 2 | purpose |
| infection → require → surgery | 30 |
| infection → require → surgical treatment | 5 |
| infection → have → surgery | 4 |
| infection → require → very surgery | 4 |
| negative | neutral | positive |
| 0.614 | 0.352 | 0.034 |
| Raw frequency | 43 |
| Normalized frequency | 0.439 |
| Modifier score | 0.567 |
| Perplexity | 147.536 |