Reoperation frequency depending on follow-up time for patients undergoing spinal surgery between 1 January 2015 and 20 May 2018.
| Follow-Up Time | 30 d (n = 2084) | 1 y (n = 1633) | 2 y (n = 978) | Entire Study Population (n = 2110) |
| Total number of patients requiring reoperation | 116 (5.6) | 164 (10.0) | 133 (13.6) | 232 (11.0) |
| 30-d reoperation frequency | 116 (5.6) | 96 (5.9) | 58 (5.9) | 118 (5.6) |
Note: For all variables, n (%) is presented.