Subject characteristics
| Continuous | ADR | Fusion | Significance |
|---|---|---|---|
| Age (mean ± SD) (y) | 45.98 ± 9.16 | 53.12 ± 9.71 | P < .01 |
| Body mass index (mean ± SD) | 28.28 ± 4.85 | 29.32 ± 8.00 | NS |
| Currently smoking [n (%)] | 5/22 (22.73%) | 2/21 (9.52%) | NS |
| Workers' compensation [n (%)] | 4/22 (18.18%) | 13/21 (61.90%) | P < .01 |
| Male [n (%)] | 15/22(68.18%) | 15/21 (71.43%) | NS |
| Previous lumbar surgery [n (%)] | 4/22 (18.18%) | 4/21 (19.05%) | NS |
| Previous chronic condition [n (%)] | 18/22 (81.82%) | 16/21 (76.19%) | NS |
| Previous surgery—non-orthopaedic [n (%)] | 2/22 (9.09%) | 3/21 (14.29%) | NS |
| Previous surgery—spine [n (%)] | 5/22 (22.73%) | 4/21 (19.05%) | NS |
| Previous surgery—other orthopaedic [n (%)] | 4/22 (18.18%) | 2/21 (9.52%) | NS |