Table 2.
Functional outcomes between the two groups preoperatively and during the 24-month follow-up period
| Full endoscopic (n = 30) | Tubular-based microscopic (n = 30) | Mean difference (95% CI) adjusted preoperative | p-value | |||
|---|---|---|---|---|---|---|
| Mean ± SD | Mean change (95% CI) | Mean ± SD | Mean change (95% CI) | |||
| VAS back pain | ||||||
| Preoperative | 7.5 ± 2.49 | Reference | 6.43 ± 3.04 | Reference | – | – |
| 1 day | 1.5 ± 2.01 | − 6 (− 6.89, − 5.11) | 1.83 ± 2.17 | − 4.6 (− 5.6, − 3.6) | − 1.4 (− 2.74, − 0.06) | 0.041* |
| 2 weeks | 1.7 ± 1.68 | − 5.8 (− 6.69, − 4.91) | 1.7 ± 1.66 | − 4.73 (− 5.74, − 3.73) | − 1.07 (− 2.41, 0.28) | 0.12 |
| 6 weeks | 2.07 ± 2.26 | − 5.43 (− 6.33, − 4.54) | 1.87 ± 2.13 | − 4.57 (− 5.57, − 3.56) | − 0.87 (− 2.21, 0.48) | 0.207 |
| 3 months | 2.33 ± 2.19 | − 5.17 (− 6.06, − 4.27) | 2.5 ± 2.52 | − 3.93 (− 4.94, − 2.93) | − 1.23 (− 2.58, 0.11) | 0.072 |
| 6 months | 1.87 ± 2.32 | − 5.63 (− 6.53, − 4.74) | 2.8 ± 2.38 | − 3.63 (− 4.64, − 2.63) | − 2 (− 3.34, − 0.66) | 0.004* |
| 12 months | 2.1 ± 2.25 | − 5.4 (− 6.29, − 4.51) | 2.83 ± 2.8 | − 3.6 (− 4.6, − 2.6) | − 1.8 (− 3.14, − 0.46) | 0.009* |
| 24 months | 2.19 ± 2 | − 5.14 (− 6.08, − 4.21) | 2.65 ± 2.45 | − 3.66 (− 4.68, − 2.63) | − 1.48 (− 2.87, − 0.09) | 0.037* |
| VAS leg | ||||||
| Preoperative | 6.83 ± 2.45 | Reference | 7.5 ± 2.16 | Reference | – | – |
| 1 day | 0.93 ± 1.55 | − 5.9 (− 6.6, − 5.2) | 0.87 ± 1.76 | − 6.63 (− 7.57, − 5.7) | 0.73 (− 0.43, 1.9) | 0.218 |
| 2 weeks | 0.27 ± 0.58 | − 6.57 (− 7.26, − 5.87) | 1.03 ± 1.59 | − 6.47 (− 7.4, − 5.53) | − 0.1 (− 1.27, 1.07) | 0.867 |
| 6 weeks | 0.3 ± 0.7 | − 6.53 (− 7.23, − 5.84) | 1 ± 1.44 | − 6.5 (− 7.44, − 5.56) | − 0.03 (− 1.2, 1.13) | 0.955 |
| 3 months | 0.47 ± 1.2 | − 6.37 (− 7.06, − 5.67) | 1.53 ± 2.19 | − 5.97 (− 6.9, − 5.03) | − 0.4 (− 1.57, 0.77) | 0.502 |
| 6 months | 0.57 ± 1.19 | − 6.27 (− 6.96, − 5.57) | 1.7 ± 2.22 | − 5.8 (− 6.74, − 4.86) | − 0.47 (− 1.63, 0.7) | 0.433 |
| 12 months | 1.07 ± 1.95 | − 5.77 (− 6.46, − 5.07) | 2.17 ± 2.63 | − 5.33 (− 6.27, − 4.4) | − 0.43 (− 1.6, 0.73) | 0.467 |
| 24 months | 1.31 ± 1.67 | − 5.56 (− 6.29, − 4.84) | 2 ± 2.4 | − 5.49 (− 6.46, − 4.53) | − 0.07 (− 1.28, 1.14) | 0.905 |
| ODI | ||||||
| Preoperative | 43.29 ± 15.8 | Reference | 45.1 ± 18.92 | Reference | – | – |
| 1 day | 15.1 ± 10.58 | − 28.19 (− 33.07, − 23.31) | 19.23 ± 13.49 | − 25.87 (− 32, − 19.73) | − 2.32 (− 10.16, 5.52) | 0.562 |
| 2 weeks | 16.09 ± 12.19 | − 27.21 (− 32.09, − 22.32) | 13.14 ± 11.83 | − 31.96 (− 38.1, − 25.83) | 4.76 (− 3.08, 12.6) | 0.234 |
| 6 weeks | 13.15 ± 12.58 | − 30.14 (− 35.03, − 25.26) | 13.93 ± 9.85 | − 31.16 (− 37.3, − 25.03) | 1.02 (− 6.82, 8.86) | 0.799 |
| 3 months | 9.41 ± 9.63 | − 33.88 (− 38.77, − 29) | 13.06 ± 14.03 | − 32.04 (− 38.17, − 25.9) | − 1.85 (− 9.69, 5.99) | 0.644 |
| 6 months | 6.74 ± 7.97 | − 36.55 (− 41.43, − 31.67) | 13.15 ± 16.1 | − 31.95 (− 38.08, − 25.81) | − 4.61 (− 12.45, 3.23) | 0.25 |
| 12 months | 9.13 ± 10.06 | − 34.16 (− 39.04, − 29.28) | 13.57 ± 15.75 | − 31.53 (− 37.67, − 25.39) | − 2.63 (− 10.47, 5.21) | 0.511 |
| 24 months | 9.48 ± 10.05 | − 33.62 (− 38.58, − 28.66) | 11.53 ± 13.21 | − 32.3 (− 38.57, − 26.04) | − 1.31 (− 9.3, 6.68) | 0.748 |
| EQ-5D | ||||||
| Preoperative | 0.419 ± 0.2107 | Reference | 0.3191 ± 0.2926 | Reference | – | – |
| 2 weeks | 0.8771 ± 0.0836 | 0.46 (0.38, 0.54) | 0.7887 ± 0.1853 | 0.47 (0.38, 0.56) | − 0.01 (− 0.13, 0.11) | 0.85 |
| 6 weeks | 0.8526 ± 0.2128 | 0.43 (0.35, 0.51) | 0.823 ± 0.1433 | 0.5 (0.42, 0.59) | − 0.07 (− 0.19, 0.05) | 0.246 |
| 3 months | 0.8722 ± 0.1868 | 0.45 (0.37, 0.53) | 0.8145 ± 0.1795 | 0.5 (0.41, 0.58) | − 0.04 (− 0.16, 0.08) | 0.486 |
| 6 months | 0.887 ± 0.1665 | 0.47 (0.39, 0.55) | 0.8477 ± 0.1591 | 0.53 (0.44, 0.62) | − 0.06 (− 0.18, 0.06) | 0.318 |
| 12 months | 0.8223 ± 0.2277 | 0.4 (0.32, 0.48) | 0.8331 ± 0.209 | 0.51 (0.43, 0.6) | − 0.11 (− 0.23, 0.01) | 0.068 |
| 24 months | 0.91 ± 0.1 | 0.48 (0.4, 0.56) | 0.86 ± 0.12 | 0.53 (0.44, 0.62) | − 0.05 (− 0.16, 0.07) | 0.451 |
| Walking time | ||||||
| Preoperative | 9.56 ± 15.91 | Reference | 15.5 ± 15.63 | Reference | – | – |
| 2 weeks | 32.17 ± 26.8 | 22.6 (12.32, 32.89) | 33.77 ± 27.47 | 18.27 (7.52, 29.02) | 4.34 (− 10.54, 19.21) | 0.568 |
| 6 weeks | 49 ± 29.78 | 39.44 (29.15, 49.72) | 42.5 ± 30.79 | 27 (16.25, 37.75) | 12.44 (− 2.44, 27.31) | 0.101 |
| 3 months | 54.83 ± 30.98 | 45.27 (34.99, 55.55) | 47.33 ± 34.36 | 31.83 (21.08, 42.58) | 13.44 (− 1.44, 28.31) | 0.077 |
| 6 months | 59.67 ± 30.9 | 50.1 (39.82, 60.39) | 51.67 ± 34.2 | 36.17 (25.42, 46.92) | 13.94 (− 0.94, 28.81) | 0.066 |
| 12 months | 58.67 ± 31.4 | 49.1 (38.82, 59.39) | 53.33 ± 36.14 | 37.83 (27.08, 48.58) | 11.27 (− 3.61, 26.15) | 0.138 |
| 24 months | 67.88 ± 33.68 | 56.95 (46.17, 67.73) | 58.77 ± 38.79 | 41.54 (30.26, 52.81) | 15.37 (− 0.23, 30.98) | 0.053 |
SD standard deviation; 95% CI, 95% confidence interval; VAS visual analog scale; ODI Oswestry Disability Index; EQ-5D European Quality of Life-5 Dimensions
* Statistically significant difference compared with preoperative value (P < 0.05)