| Measurement time | Minimum | Maximum | Mean | Standard deviation |
IVSRO* (n = 30) | Before surgery | 28 | 32 | 30.5 | 1.4 |
1 week after surgery | 30 | 34 | 31.4 | 1.3 | |
12 weeks after surgery | 30 | 33 | 31.4 | 1 | |
BSSRO** (n = 30) | Before surgery | 29 | 34 | 31.6 | 1.6 |
1 week after surgery | 31 | 34 | 32.1 | 1 | |
12 weeks after surgery | 30 | 34 | 32.4 | 1.2 |