Patient and healthcare characteristics before and during COVID-19
| Pre-COVID-19 | During COVID-19 | P value | |
| N (%) | 38 741 (76.0) | 12 245 (24.0) | |
| Age, median (IQR) | 67 (59, 73) | 66 (57, 73) | <0.001 |
| Female, n (%) | 22 858 (59.0) | 6943 (56.7) | <0.001 |
| Race, n (%) | |||
| Black | 3256 (8.4) | 1088 (8.9) | 0.038 |
| White | 31 940 (82.4) | 9971 (81.4) | |
| Other | 3545 (9.2) | 1186 (9.7) | |
| Deyo index, n (%) | <0.001 | ||
| 0–1 | 35 743 (92.2) | 11 139 (91.0) | |
| 2 | 2018 (5.2) | 707 (5.8) | |
| 3+ | 980 (2.5) | 399 (3.3) | |
| Urban hospital, n (%) | 33 521 (86.5) | 10 556 (86.2) | 0.155 |
| Teaching hospital, n (%) | 20 171 (52.1) | 6350 (51.9) | <0.001 |
| Hospital bed size, n (%) | <0.001 | ||
| 0–300 | 15 037 (38.8) | 4521 (36.9) | |
| 300–500 | 11 856 (30.6) | 3849 (31.4) | |
| 500+ | 11 848 (30.6) | 3875 (31.6) | |
| Region, n (%) | <0.001 | ||
| Midwest | 9072 (23.4) | 2941 (24.0) | |
| Northeast | 10 706 (27.6) | 3035 (24.8) | |
| South | 15 346 (39.6) | 5186 (42.4) | |
| West | 3617 (9.3) | 1083 (8.8) | |
| Procedure, n (%) | <0.001 | ||
| TKA | 14 791 (38.2) | 3751 (30.6) | |
| THA | 10 871 (28.1) | 2733 (22.3) | |
| Laminectomy | 740 (1.9) | 511 (4.2) | |
| Spinal fusion | 7393 (19.1) | 3290 (26.9) | |
| Shoulder and elbow arthroplasty | 3658 (9.4) | 1442 (11.8) | |
| Foot and ankle | 259 (0.7) | 99 (0.8) | |
| Hip revision | 363 (0.9) | 181 (1.5) | |
| Knee revision | 666 (1.7) | 238 (1.9) |
THA, total hip arthroplasty; TKA, total knee arthroplasty.