Spinal alignment/Roussouly type | Observed (%) | Normal population (%) | P-value |
1 | 17 | 21.3 | n.s. |
2 | 62.2 | 11.3 | <0.001 |
3 | 17 | 37.5 | n.s. |
4 | 3.8 | 30 | <0.001 |