Impact of LOS on PROMs.
| PROM | LOS ≥45 h, Mean ± SD | LOS <45 h, Mean ± SD | P Valuea |
| VAS back | |||
| Preoperative | 6.5 ± 2.3 | 6.7 ± 2.6 | 0.673 |
| 6 wk | 4.3 ± 2.7 | 3.8 ± 2.5 | 0.257 |
| 12 wk | 4.0 ± 2.6 | 3.3 ± 2.6 | 0.212 |
| 6 mo | 3.0 ± 2.6 | 3.4 ± 2.8 | 0.511 |
| 1 y | 3.0 ± 3.5 | 2.1 ± 3.0 | 0.657 |
| 2 y | 8.5 ± 0.0 | 6.4 ± 1.6 | 0.377 |
| VAS leg | |||
| Preoperative | 5.1 ± 2.7 | 4.5 ± 3.4 | 0.813 |
| 6 wk | 4.5 ± 4.3 | 3.3 ± 2.4 | 0.263 |
| 12 wk | 3.2 ± 2.8 | 2.5 ± 2.6 | 0.662 |
| 6 mo | 2.0 ± 2.6 | 2.6 ± 3.1 | 0.613 |
| 1 y | 2.2 ± 3.7 | 1.1 ± 1.7 | 0.489 |
| 2 y | 6.5 ± 0.0 | 6.3 ± 2.6 | 0.964 |
| ODI | |||
| Preoperative | 39.4 ± 17.5 | 35.7 ± 15.8 | 0.477 |
| 6 wk | 45.1 ± 32.5 | 28.3 ± 14.8 | 0.024 |
| 12 wk | 29.3 ± 16.1 | 20.3 ± 12.4 | 0.082 |
| 6 mo | 22.3 ± 20.2 | 20.2 ± 15.8 | 0.739 |
| 1 y | 30.5 ± 24.2 | 14.9 ± 16.2 | 0.153 |
| 2 y | 40.0 ± 0.0 | 28.5 ± 13.7 | 0.507 |
| SF-12 PCS | |||
| Preoperative | 27.1 ± 6.3 | 32.6 ± 9.5 | 0.046 |
| 6 wk | 34.0 ± 11.8 | 34.8 ± 8.4 | 0.838 |
| 12 wk | 32.2 ± 5.1 | 41.5 ± 8.7 | 0.014 |
| 6 mo | 40.3 ± 8.1 | 40.0 ± 9.5 | 0.920 |
| 1 y | 37.6 ± 9.1 | 45.9 ± 11.0 | 0.193 |
| 2 y | 36.2 ± 2.5 | 44.6 ± 11.8 | 0.271 |
| PROMIS-PF | |||
| Preoperative | 34.4 ± 5.0 | 38.4 ± 5.8 | 0.072 |
| 6 wk | 40.8 ± 2.6 | 40.0 ± 5.9 | 0.847 |
| 12 wk | 40.2 ± 4.6 | 44.6 ± 9.2 | 0.271 |
| 6 mo | 43.0 ± 7.2 | 47.2 ± 6.5 | 0.199 |
| 1 y | 44.0 ± 9.1 | 48.7 ± 11.0 | 0.411 |
| 2 y | 47.2 ± 9.0 | 49.6 ± 12.2 | 0.823 |
Note: Boldface indicates statistical significance.
↵a P values calculated using Student’s t test for independent samples.
LOS, length of stay; ODI, Oswestry Disability Index; PROMIS-PF, patient-reported outcome measurement information system physical function; PROMs, patient-reported outcome measures; SF-12 PCS, 12-item short form physical composite score; VAS, visual analog scale.