Table 1 Grading of complications according to Clavien-Dindo

1A

Recovery after non-invasive treatment (e.g., medication, physical therapy)

1B

Recovery after invasive treatment (except for operation in an OR) or admission to intensive care

2

Recovery after (re-)operation in an OR

3A

Complication still persists or is treated at the time of registration

3B

Complication resulting in permanent loss of function or disability

4

Death