Table 3.
Radiographic results
| Parameters | Younger group (< 65 yrs) | Elderly group (> 66 yrs) | P value (Student’s t-test) |
|---|---|---|---|
| Dorr bone type [25] | |||
| A | 108 hips (95 %) | 14 hips (12.5 %) | <0.0001 |
| B | 6 hips (5 %) | 28 hips (25 %) | |
| C | – | 70 hips (62.5 %) | |
| Femoral component position | |||
| Neutral position | 107 hips (94 %) | 106 hips (95 %) | 0.912 |
| Varus position | 5 hips (4 %) | 6 hips (5 %) | |
| Valgus position | 2 hips (2 %) | – | |
| Sagittal plane | |||
| Anatomical | 114 hips (100 %) | 111 hips (100 %) | 1.000 |
| Center of rotation | |||
| Horizontal (mm) | 40.8 (34–47) | 39.8 (35–49) | 0.259 |
| Vertical (mm) | 14.9 (12–22) | 15.7 (11–25) | 0.192 |
| Femoral offset (mm) | 41.7 (34–49) | 41.3 (35–51) | 0.818 |
| Abductor moment arm (mm) | 45.1 (39−84) | 44.2 (37 −83) | 0.914 |
| Femoral neck length (mm) | 34.5 (29−42) | 35.1 (31−39) | 0.782 |
| Limb-length discrepancy (cm) | 0.3 ± 0.5 (−1.3–1.2) | 0.5 ± 0.6 (−1.3–1.3) | 0.705 |
| Radiolucent line (> 1 mm) | 0 hip (0 %) | 0 hip (0 %) | – |
| Migration of femoral Component (< 1 mm) but stabilized | 1 hip (1 %) | 1 hip (1 %) | – |