Summary of causation of “Poor” or “Worse” outcomes.
| Recurrent operative site symptoms | 2 | |
| Stenosis | 2 | |
| Concurrent Perineural Scarring | 1 | |
| Contra-lateral same level stenosis | 3 | |
| Adjacent level deterioration | 6 | |
| Disc Protrusion | 2 | |
| Degenerative Spondylolisthesis | 2 | |
| Foraminal Stenosis | 2 | |
| Self-excluded to physical review | Multiple Sclerosis | 1 |
| Ovarian Cancer & Fusion | 1 | |
| Sequelae of Fusion | 2 |