TABLE II.
Characteristics of Patients with All-Cause or TKA-Specific Readmission 30 Days After TKA
| 30-Day Readmissions* |
||||
| Patient Characteristics | CMS TKA-Specific† (N = 2,449) | Expanded TKA-Specific‡ (N = 6,784) | All-Cause§ (N = 22,076) | No Readmission (N = 355,629) |
| Age (yr) | ||||
| Mean ± stand. dev. | 67.6 ± 11.0 | 67.4 ± 11.1 | 69.2 ± 10.5 | 66.8 ± 10.3 |
| Median | 68 | 68 | 70 | 67 |
| Q1, Q3 | 60, 76 | 60, 76 | 62, 77 | 60, 74 |
| Sex (no. [%]) | ||||
| Male | 965 (39.4%) | 2,748 (40.5%) | 8,154 (36.9%) | 120,026 (33.8%) |
| Female | 1,484 (60.6%) | 4,036 (59.5%) | 13,922 (63.1%) | 235,603 (66.2%) |
| Race/ethnicity (no. [%]) | ||||
| White | 1,814 (74.1%) | 4,965 (73.2%) | 16,619 (75.3%) | 267,516 (75.2%) |
| Black | 265 (10.8%) | 736 (10.8%) | 1,983 (9.0%) | 32,226 (9.1%) |
| Hispanic | 139 (5.7%) | 456 (6.7%) | 1,122 (5.1%) | 20,644 (5.8%) |
| Asian | 20 (0.8%) | 72 (1.1%) | 197 (0.9%) | 4,930 (1.4%) |
| Other | 129 (5.3%) | 348 (5.1%) | 876 (4.0%) | 18,123 (5.1%) |
| Missing | 82 (3.3%) | 207 (3.1%) | 1,279 (5.8%) | 12,190 (3.4%) |
| Insurance status (no. [%]) | ||||
| Medicare | 1,472 (60.1%) | 4,022 (59.3%) | 14,233 (64.5%) | 195,339 (54.9%) |
| Medicaid | 147 (6.0%) | 429 (6.3%) | 856 (3.9%) | 16,468 (4.6%) |
| Private | 685 (28.0%) | 1,920 (28.3%) | 5,975 (27.1%) | 121,482 (34.2%) |
| Workers’ Compensation | 91 (3.7%) | 272 (4.0%) | 651 (2.9%) | 14,316 (4.0%) |
| Other | 54 (2.2%) | 141 (2.1%) | 361 (1.6%) | 8,024 (2.3%) |
| Surgical indication (no. [%]) | ||||
| Osteoarthritis | 2,282 (93.2%) | 6,364 (93.8%) | 20,705 (93.8%) | 336,094 (94.5%) |
| Inflammatory arthritis | 146 (6.0%) | 370 (5.5%) | 1,205 (5.5%) | 17,333 (4.9%) |
| Osteonecrosis | 21 (0.9%) | 50 (0.7%) | 166 (0.8%) | 2,202 (0.6%) |
| Bilateral TKA (no. [%]) | 144 (5.9%) | 269 (4.0%) | 2,291 (10.4%) | 18,751 (5.3%) |
| In-hospital complications (no. [%]) | ||||
| Medical | 226 (9.2%) | 470 (6.9%) | 1,413 (6.4%) | 9,404 (2.6%) |
| Surgical | 164 (6.7%) | 336 (5.0%) | 798 (3.6%) | 6,456 (1.8%) |
| Length of hospital stay (days) | ||||
| Mean ± stand. dev. | 4.9 ± 4.3 | 4.7 ± 3.9 | 4.8 ± 3.3 | 4.1 ± 2.4 |
| Median | 4 | 4 | 4 | 3 |
| Q1, Q3 | 3, 5 | 3, 5 | 3, 5 | 3, 5 |
| Discharge disposition (no. [%]) | ||||
| Home | 948 (38.7%) | 2,795 (41.2%) | 5,388 (24.4%) | 153,069 (43.0%) |
| Short-term hospital | 197 (8.0%) | 376 (5.5%) | 1,037 (4.7%) | 5,285 (1.5%) |
| Skilled nursing facility | 900 (36.7%) | 2,726 (40.2%) | 6,219 (28.2%) | 110,916 (31.2%) |
| Rehabilitation facility | 212 (8.7%) | 437 (6.4%) | 4,426 (20.0%) | 50,852 (14.3%) |
| Other facility | 192 (7.8%) | 450 (6.6%) | 5,006 (22.7%) | 35,507 (10.0%) |
*
Readmission categories are not mutually exclusive.
†
Readmissions due to any of 8 diagnoses designated by the CMS as TKA-specific complications (see Appendix).
‡
Readmissions due to a diagnosis on an expanded list of TKA-specific complications, including 22 additional TKA-specific complications selected by a group of experts (see Appendix).
§
Readmissions due to all causes, including 918 conditions not included in the CMS-defined or expanded list of TKA-specific complications (see Appendix).