Table 4.
Postoperative radiographic analysis based on inlier/outlier definition
| Radiographic analysis |
Within safe zone (n = 37) |
Outliers (n = 23) |
p value |
|---|---|---|---|
| Cup anteversion angle (°)* | 14 (5–25) | 19 (0–37) | 0.01 |
| Cup abduction angle (°)* | 38 (30–50) | 31 (24–51) | 0.03 |
| Amount of wear (mm)† | 0.72 ± 0.73 | 0.75 ± 0.71 | 0.5 |
| Linear wear (mm/year)† | 0.07 ± 0.07 | 0.07 ± 0.07 | 0.9 |
| Cup tilt > 3° (number) | 0 | 0 | NA |
| Radiographic osteolysis (number) | 3 (8%) | 1 (4%) | 1 |
* Median (range); †mean ± SD; Within safe zone = cup orientation abduction angle of 40° ± 10° and an anteversion angle of 15° ± 10°; Outliers = cup orientation outside of the Lewinnek safe zone; NA = no statistical analysis available.