Table 1 Baseline characteristics of the Total Knee Arthroplasty patients and by neighborhood Immigrant proportion
Characteristic | All primary TKA (N = 3898) | Immigrant proportion <  10% (n = 1032) | Immigrant proportion 10 to <  40% (n = 2527) | Immigrant proportion ≥ 40% (n = 339) | p-value (<  10% v. ≥ 40%) |
|---|---|---|---|---|---|
Patient demographics | |||||
 Age at surgery (years), mean ± SD | 67.8 ± 9.5 | 67.0 ± 9.2 | 68.1 ± 9.6 | 67.8 ± 9.6 | 0.16 |
 Sex: female, n (%) | 2346 (60.2%) | 568 (55.0%) | 1538 (60.9%) | 240 (70.8%) | < 0.001 |
 BMI (kg/m2), mean ± SD | 30.0 ± 5.9 | 30.1 ± 5.7 | 29.9 ± 6.0 | 31.0 ± 6.6 | 0.03 |
Race, n (%) |  |  |  |  | < 0.001 |
 White | 3568 (91.5%) | 1012 (98.1%) | 2297 (90.9%) | 259 (76.4%) |  |
 Black | 174 (4.5%) | 5 (0.5%) | 128 (5.1%) | 41 (12.1%) |  |
 Asian | 74 (1.9%) | 9 (0.9%) | 47 (1.9%) | 18 (5.3%) |  |
 Other | 56 (1.4%) | 5 (0.5%) | 35 (1.4%) | 16 (4.7%) |  |
 Unknown | 26 (0.7%) | 1 (0.1%) | 20 (0.8%) | 5 (1.5%) |  |
Ethnicity, n (%) |  |  |  |  | < 0.001 |
 Hispanic | 129 (3.3%) | 5 (0.5%) | 35 (1.4%) | 16 (4.7%) |  |
Patient status | |||||
 One or more comorbidities | 1057 (27.1%) | 267 (25.9%) | 674 (26.7%) | 116 (34.2%) | 0.003 |
Sociodemographic characteristics | |||||
 Education level (highest), n (%) |  |  |  |  | < 0.001 |
  Some high school, high school graduate or some college (< College graduate) | 1366 (35.6%) | 359 (36.0%) | 849 (35.1%) | 158 (49.4%) |  |
  College graduate or Masters, professional or doctorate degree (> College graduate) | 2370 (63.4%) | 639 (64.0%) | 1569 (64.9%) | 162 (50.6%) |  |
  Lives alone, n (%) | 860 (22.4%) | 159 (15.6%) | 598 (24.1%) | 103 (31.0%) | < 0.001 |
Census tract characteristics | |||||
 Number of census tracts, n (%) | 1937 (100%) | 498 (25.7%) | 1196 (61.7%) | 243 (12.5%) |  |
 Poverty, n (%) |  |  |  |  | < 0.001 |
   <  10% | 3175 (81.5%) | 975 (94.5%) | 2078 (82.2%) | 122 (36.0%) |  |
  10% – <  20% | 511 (13.1%) | 48 (4.7%) | 300 (11.9%) | 163 (48.1%) |  |
   ≥ 20% | 212 (5.4%) | 9 (0.9%) | 149 (5.9%) | 54 (15.9%) |  |
Patient-reported outcomes | |||||
 HSS expectation survey, mean ± SD | 79.2 ± 17.6 | 80.1 ± 17.7 | 78.8 ± 17.4 | 79.5 ± 18.3 | 0.63 |
 Pre-operative survey results, mean ± SD | |||||
  WOMAC pain | 54.4 ± 17.5 | 54.9 ± 17.6 | 54.7 ± 17.3 | 51.0 ± 18.9 | < 0.001 |
  WOMAC function | 53.7 ± 17.6 | 54.2 ± 16.9 | 54.1 ± 17.7 | 49.1 ± 17.3 | < 0.001 |
 2-year post-operative survey results | |||||
  WOMAC pain, mean ± SD | 87.9 ± 15.6 | 89.3 ± 14.7 | 87.5 ± 15.7 | 86.5 ± 17.5 | 0.01 |
  WOMAC function, mean ± SD | 85.6 ± 16.1 | 86.7 ± 14.9 | 85.4 ± 16.2 | 83.6 ± 17.9 | 0.005 |