Table 2.
Preoperative and postoperative radiographic parameter values, by failure group
| Variable | Total (n = 235) | Success (n = 221) | Failure (n = 14) | p-value |
|---|---|---|---|---|
| Preoperative | ||||
| Reducible disc height (%) | 13.65 (8.4–21.18) | 14.25 (8.68–22.13) | 8.04 (5.09–11.52) | 0.003 |
| Disc height (mm) | 8.07 (6.61–9.85) | 8.08 (6.61–9.80) | 7.47 (6.99–10.04) | 0.74 |
| Foraminal height (mm) | 17 (14.98–18.69) | 17.05 (14.95–18.8) | 16.58 (15.9–18.46) | 0.87 |
| Canal diameter (mm) | 12 (10.19–13.91) | 11.9 (10.17–13.9) | 12.76 (12.18–14.45) | 0.32 |
| Lordotic angle (°) | 10 (5–15) | 10 (5–15) | 9 (7–10) | 0.40 |
| Postoperative | ||||
| Disc height (mm) | 12.2 (10.4–13.4) | 12.195 (10.53–13.42) | 9.36 (8.5–11.45) | 0.001 |
| Foraminal height (mm) | 19.5 (17.7–21.6) | 19.7 (17.9–21.6) | 18.0 (16.6–19.1) | 0.23 |
| Canal diameter (mm) | 14.2 (12.5–16.1) | 14.2 (12.4–16.1) | 14.3 (13.1–15.5) | 0.64 |
| Lordotic angle (°) | 13 (7–17) | 13 (7–17) | 10.5 (4–15) | 0.22 |
| Cage subsidence (mm) | 2 (0.1–3.5) | 2 (0–3.2) | 5.1 (2.5–8.8) | < 0.001 |
| Cage subsidence | ||||
| Grade 0 | 135 (57.5) | 133 (60.2) | 2 (14.3) | |
| Grade 1 | 77 (32.8) | 73 (33.0) | 4 (28.6) | |
| Grade 2 | 12 (5.1) | 11 (5.0) | 1 (7.1) | |
| Grade 3 | 11 (4.7) | 4 (1.8) | 7 (50) | < 0.001 |
Values are presented as median (interquartile range) or number (%).