| HV angles | Pre | Post | ||||||
| R | L | R | L | |||||
| N | % | N | % | N | % | N | % | |
| <15 normal | 0 | 0.0 | 0 | 0.0 | 5 | 31.3 | 7 | 35.0 |
| 15 - 20 mild | 0 | 0.0 | 0 | 0.0 | 5 | 31.3 | 8 | 40.0 |
| 21 - 39 moderate | 9 | 56.2 | 13 | 65.0 | 6 | 37.5 | 5 | 25.0 |
| >39 severe | 7 | 43.8 | 7 | 35.0 | 0 | 0.0 | 0 | 0.0 |
| Total | 16 | 100.0 | 20 | 100.0 | 16 | 100.0 | 20 | 100.0 |
| P value | 0.026 | 0.017 | ||||||