Table 1.
Demographic characteristics
| Hip replacement | Knee replacement | |
|---|---|---|
| Total number, n | 6238 | 7501 |
| Age, mean (SD), years | 67.59 (10.63) | 69.67 (9.52) |
| Female | 53.2% | 67.7% |
| Bilateral operation, n (%) | 418 (6.7%) | 1225 (16.3%) |
| BMI, mean (SD), kg/m2* | 28.2 (4.7) | 29.9 (4.8) |
| Charlson Comorbidity Index** | ||
| 0 | 4685 (75.1%) | 5239 (69.8%) |
| 1 | 1128 (18.1%) | 1621 (21.6%) |
| > 2 | 425 (6.8%) | 641 (8.5%) |
| Diabetes, n (%) | 473 (7.6%) | 744 (9.9%) |
| Cardiac disease***, n (%) | 699 (11.2) | 904 (12.1%) |
| Psychotic disorder, n (%) | 92 (1.5%) | 137 (1.8%) |
| Neurodegenerative disease (Alzheimer or Parkinson), n (%) | 86 (1.4%) | 111 (1.5%) |
| Pulmonary disease, n (%) | 373 (6.0%) | 619 (8.3%) |
| Hypertension, n (%) | 1656 (26.5%) | 2491 (33.2%) |
| History of malignancy, n (%) | 182 (2.9%) | 273 (3.6%) |
| Epilepsy, n (%) | 67 (1.1%) | 74 (1.0%) |
| Antidepressant****, n (%) | 621 (10.0%) | 840 (11.2%) |
| Preoperative analgesic use, n (%) | ||
| Any analgesic | 2959 (47.4%) | 2960 (39.5%) |
| Acetaminophen | 870 (13.9%) | 894 (11.9%) |
| NSAID | 2095 (33.6%) | 1983 (26.4%) |
| Opioid | 870 (13.9%) | 685 (9.1%) |
| KSS Knee Score, n (%) | ||
| Poor (< 60) | 3965 (52.9%) | |
| Fair (60–70) | 642 (8.6%) | |
| Good or excellent (> 70) | 277 (3.7%) | |
| Missing | 2617 (34.9%) | |
| KSS Function Score, n (%) | ||
| Poor (< 60) | 2760 (36.8%) | |
| Fair (60–70) | 623 (8.3%) | |
| Good or Excellent (> 70) | 1473 (19.6%) | |
| Missing | 2645 (35.3%) | |
| Harris Hip Score, n (%) | ||
| Poor (< 70) | 3801 (60.9%) | |
| Fair (70–80) | 240 (3.8%) | |
| Good or excellent (> 80) | 59 (0.9%) | |
| Missing | 2138 (34.3%) | |
SD standard deviation, BMI body mass index
*Missing on 825 (13.2%) of hip and 997 (13.3%) of knee patients
** Modified Charlson Comorbidity Index
***Coronary artery disease, heart failure, chronic arrhythmia
****Redeemed antidepressant 1 year before surgery