Impact of patient risk factors on fusion success.
| Variable | Fusion Success n/N (%) | P |
| BMI risk factor | ||
| ≥30 | 72/79 (91.1%) | 0.2 |
| <30 | 53/63 (84.1%) | |
| Nicotine risk factor | ||
| Smoker | 22/27 (81.5%) | 0.2 |
| Nonsmoker | 103/113 (92.9%) | |
| Age risk factor | ||
| 65+ y | 70/76 (92.1%) | 0.1 |
| <65 y | 55/66 (83.3%) | |
| Diabetes risk factor | ||
| Diabetes | 27/32 (84.4%) | 0.5 |
| No diabetes | 98/110 (89.1%) | |
| Osteoporosis risk factor | ||
| Yes | 11/14 (78.6%) | 0.4 |
| No | 114/128 (89.1%) | |
| Prior fusion | ||
| Yes | 20/22 (90.9%) | 1.0 |
| No | 105/120 (87.5%) | |
| Multiple levels | ||
| Multiple | 114/128 (89.1%) | 0.4 |
| Single | 11/14 (78.6%) |
Abbreviation: BMI, body mass index.