Table 1.
Acetabular and orientational variables
| Acetabular variable | Value at anatomic position | Acetabular variable range (net range) | Orientational variable | Individual variance contribution (%) | Significance of variance contribution (p value) | Allowable change in orientational variable with ± 3° change in acetabular variable |
|---|---|---|---|---|---|---|
| AAI | 28° | −7° to 44° (51°) | Obliquity | 11.5 | < 0.0001 | +/− 6.8° |
| Rotation | 0.0 | 0.93 | NS | |||
| Tilt | 62.0 | < 0.0001 | +/− 3.9° | |||
| AAF | 24° | −5° to 43° (48°) | Obliquity | 10.4 | < 0.0001 | +/− 7.1° |
| Rotation | 0.0 | 0.70 | NS | |||
| Tilt | 65.1 | < 0.0001 | +/− 4.0° | |||
| AASA | 67° | 41° to 136° (95°) | Obliquity | 41.1 | < 0.0001 | +/− 1.6° |
| Rotation | 0.0 | 0.55 | NS | |||
| Tilt | 23.0 | < 0.0001 | +/− 2.8° | |||
| PASA | 115° | 91° to 146° (55°) | Obliquity | 39.7 | < 0.0001 | +/− 3.0° |
| Rotation | 0.8 | 0.0538 | NS | |||
| Tilt | 20.1 | < 0.0001 | +/− 5.8° | |||
| HASA | 182° | 145° to 277° (132°) | Obliquity | 53.7 | < 0.0001 | +/− 1.1° |
| Rotation | 0.5 | 0.18 | NS | |||
| Tilt | 3.3 | 0.0004 | +/− 5.9° |
AAI = acetabular anteversion referenced by posterior ischia; AAF = acetabular anteversion referenced by femoral head centers; AASA = anterior acetabular sector angle; PASA = posterior acetabular sector angle; HASA = horizontal acetabular sector angle; NS = not significant.