Demographics of patients in Ontario who underwent surgery for degenerative disease of the lumbar spine between Apr. 1, 1995, and Dec. 31, 2001, by surgeon specialty and volume
| Characteristic | Surgeon specialty | Surgeon volume | ||
|---|---|---|---|---|
| Neurosurgery | Orthopedic | Low volume | High volume | |
| No. of patients | 2687 | 3441 | 2295 | 3833 |
| Age, mean (range) yr | 68 (50–92) | 67 (50–94) | 68 (50–94) | 68 (50–91) |
| Female, no. (%) | 1365 (50.8) | 1995 (58.0) | 1234 (53.8) | 2126 (55.5) |
| Charlson ≥ 1, no. (%) | 744 (27.7) | 929 (27.0) | 651 (28.4) | 1022 (26.7) |