Table 3.
Multivariate model predicting inpatient discharge following primary unilateral total knee arthroplasty
| Variable | Home Discharge n=547, %(#) | Inpatient Discharge n=186, %(#) | Adjusted OR | Adjusted 95% CI | Adjusted P-Value |
|---|---|---|---|---|---|
| Age Group (ref = <55) | 87 (110) | 13 (17) | |||
| 55-59 | 85 (99) | 15 (18) | 1.35 | 0.57-3.23 | 0.496 |
| 60-64 | 84 (112) | 16 (21) | 1.46 | 0.63-3.38 | 0.381 |
| 65-69 | 76 (111) | 24 (36) | 3.06 | 1.41-6.64 | 0.005 |
| 70-74 | 65 (55) | 35 (29) | 4.95 | 2.08-11.78 | <0.001 |
| 75-79 | 53 (38) | 47 (34) | 11.13 | 4.61-26.84 | <0.001 |
| 80+ | 41 (24) | 59 (34) | 16.12 | 6.38-40.69 | <0.001 |
| Surgery Day (ref = Monday) | 73 (105) | 27 (39) | |||
| Tuesday | 79 (214) | 21 (57) | 0.44 | 0.20-0.98 | 0.044 |
| Wednesday | 65 (68) | 35 (36) | 0.66 | 0.28-1.54 | 0.337 |
| Thursday | 75 (124) | 25 (41) | 0.30 | 0.13-0.74 | 0.009 |
| Friday | 70 (38) | 30 (16) | 0.58 | 0.21-1.59 | 0.291 |
| Gender (ref = Male) | 83 (263) | 17 (53) | |||
| Female | 68 (286) | 32 (136) | 2.67 | 1.68-4.23 | <0.001 |
| VR-12 PCS (ref = 40+) | 81 (130) | 18 (29) | |||
| 30-40 | 82 (124) | 18 (27) | 0.99 | 0.51-1.90 | 0.972 |
| 20-30 | 68 (153) | 32 (71) | 2.37 | 1.32-4.25 | 0.004 |
| <20 | 69 (55) | 31 (25) | 2.01 | 0.93-4.35 | 0.075 |
| Surgeon (ref=Surgeon 1) | 65 (119) | 35 (64) | |||
| Surgeon 2 | 70 (86) | 30 (36) | 0.66 | 0.32-1.38 | 0.274 |
| Surgeon 3 | 65 (72) | 35 (39) | 2.11 | 0.88-5.02 | 0.092 |
| Surgeon 4 | 74 (37) | 26 (13) | 0.21 | 0.07-0.61 | 0.004 |
| Surgeon 5 | 87 (138) | 13 (21) | 0.26 | 0.12-0.54 | <0.001 |
| Surgeon 6 | 86 (97) | 14 (16) | 0.37 | 0.15-0.90 | 0.028 |
| Charlson (ref=0) | 82 (348) | 18 (78) | |||
| 1-3 | 74 (73) | 26 (25) | 2.51 | 1.35-4.70 | 0.004 |
| 4-5 | 66 (97) | 34 (50) | 1.76 | 1.01-3.05 | 0.046 |
| 6-9 | 45 (29) | 55 (35) | 2.44 | 1.22-4.88 | 0.011 |
| BMI Group (ref = Normal – Overweight <30) | 80(109) | 20 (27) | |||
| Obese 30-39 | 79 (97) | 21 (26) | 0.94 | 0.44-2.00 | 0.868 |
| Morbid Ob 40+ | 58 (32) | 42 (23) | 4.26 | 1.81-10.03 | 0.001 |
| Pre-Op ROM Group (ref = >110) | 82(130) | 18 (29) | |||
| 90-110 | 72 (151) | 28 (59) | 1.43 | 0.76-2.69 | 0.273 |
| <90 | 61 (30) | 39 (19) | 1.85 | 0.78-4.34 | 0.160 |
| Laterality (ref = left) | 72 (249) | 28 (98) | |||
| Right | 77 (300) | 23 (91) | 0.63 | 0.43-0.92 | 0.016 |
Missing values for each variable were included in the model, but not displayed. Hence, numbers and percentages may not add up to 738 and 100 for each variable and value. CI indicates confidence interval; OR, odds ratio; ref, reference group; Charlson, Charlson Comorbidity Index; Ob, obesity.
Clustered on the 708 individual patients among the 738 primary unilateral TKAs.