Table 2.
Univariate and Multivariable-adjusted Hazard of Postoperative Periprosthetic fracture following Primary Total Knee Replacement (TKA)
| Variable | Total (n=17633) | Periprosthet ic fractures (n=188) | Univariate Hazard Ratio (95% CI) | Multivariable Hazard a Ratio (95% CI) | Multivariable Hazard Ratio (95% CI) b |
|---|---|---|---|---|---|
| Heart Disease (MI, CHF) | p=0.419 | p=0.96 | |||
| No | 15839 | 168 (1%) | 1.00 (ref) | 1.00 (ref) | |
| Yes | 1794 | 20 (1%) | 1.21 (0.76, 1.93) | 1.01 (0.61, 1.67) | |
| Peripheral Vascular Disease | p=0.16 | p=0.48 | |||
| No | 16527 | 174 (1%) | 1.00 (ref) | 1.00 (ref) | |
| Yes | 1106 | 14 (1%) | 1.48 (0.86, 2.55) | 1.23 (0.69, 2.19) | |
| Cereberovascular disease (including hemiplegia) | p=0.693 | p=0.73 | |||
| No | 15955 | 171 (1%) | 1.00 (ref) | 1.00 (ref) | |
| Yes | 1678 | 17 (1%) | 1.11 (0.67, 1.82) | 0.91 (0.53, 1.55) | |
| Moderate-severe Renal Disease | p=0.037 | p=0.13 | P=0.11 | ||
| No | 16313 | 170 (1%) | 1.00 (ref) | 1.00 (ref) | 1.00 (ref) |
| Yes | 1320 | 18 (1%) | 1.68 (1.03, 2.73) | 1.49 (0.89, 2.49) | 1.51 (0.92, 2.49) |
| Peptic Ulcer Disease | p<0.001 | p=0.0014 | P=0.0011 | ||
| No | 15912 | 154 (1%) | 1.00 (ref) | 1.00 (ref) | 1.00 (ref) |
| Yes | 1721 | 34 (2%) | 2.08 (1.43, 3.02) | 1.87 (1.28, 2.75) | 1.88 (1.29, 2.75) |
| Chronic Obstructive Pulmonary Disease (COPD) | p=0.002 | p=0.02 | P=0.01 | ||
| No | 15405 | 154 (1%) | 1.00 (ref) | 1.00 (ref) | 1.00 (ref) |
| Yes | 2228 | 34 (2%) | 1.78 (1.22, 2.57) | 1.62 (1.10, 2.40) | 1.62 (1.11, 2.39) |
| Diabetes (with or without organ damage) | p=0.161 | p=0.24 | |||
| No | 15416 | 163 (1%) | 1.00 (ref) | 1.00 (ref) | |
| Yes | 2217 | 25 (1%) | 1.35 (0.89, 2.06) | 1.30 (0.84, 2.03) | |
| Other (dementia, liver disease, AIDS) | p=0.042 | p=0.07 | P=0.13 | ||
| No | 16460 | 171 (1%) | 1.00 (ref) | 1.00 (ref) | 1.00 (ref) |
| Yes | 1173 | 17 (1%) | 1.68 (1.02, 2.77) | 1.64 (0.96, 2.81) | 1.48 (0.89, 2.46) |
| Connective tissue Disease | p=0.056 | p=0.55 | |||
| No | 16037 | 161 (1%) | 1.00 (ref) | 1.00 (ref) | |
| Yes | 1596 | 27 (2%) | 1.49 (0.99, 2.24) | 1.17 (0.69, 1.99) | |
| Cancer | p=0.785 | p=0.17 | |||
| No | 14708 | 161 (1%) | 1.00 (ref) | 1.00 (ref) | |
| Yes | 2925 | 27 (1%) | 0.94 (0.63, 1.42) | 0.73 (0.47, 1.15) |
a
Multivariable model simultaneously adjusted for all variables including age, gender, ASA class, BMI, operative diagnosis, implant fixation (cement status) and each Deyo-Charlson comorbidity category; 17,499 of the 17,633 TKAs were available for the multivariable analyses
b
Multivariable model adjusted only for comorbidities significant in univariate analyses with p-value <0.05
Ref, reference category