Table 3.
Cup and stem rotation and translation at 10 years
| Variable | PE | XLPE | p value* |
|---|---|---|---|
| Cup rotation (°) | n = 26 | n = 24 | |
| x-axis (forward tilt +) | 0.05 (0.10) | −0.06 (0.13) | 0.55 |
| y-axis (anteversion +) | −0.02 (0.14) | −0.17 (0.14) | 0.53 |
| z-axis (increased inclination +) | 0.60 (0.58) | 0.24 (0.10) | 0.51 |
| Cup translation (mm) | n = 26 | n = 24 | |
| x-axis (medial +) | −0.29 (0.22) | −0.15 (0.05) | 0.71 |
| y-axis (proximal +) | 0.29 (0.17) | 0.22 (0.08) | 0.61 |
| z-axis (forward +) | −0.003 (0.08) | −0.13 (0.07) | 0.32 |
| Stem rotation (°) | n = 26 | n = 20 | |
| x-axis (forward tilt +) | −0.06 (0.05) | −0.15 (0.07 | 0.81 |
| y-axis (anteversion +) | −0.80 (0.35) | −0.55 (0.24) | 0.65 |
| z-axis (valgus +) | −0.15 (0.05) | 0.03 (0.04) | 0.005 |
| Stem migration (mm) | n = 27 | n = 23 | |
| y-axis (proximal +) | −0.51 (0.14) | −0.15 (0.06) | 0.05 |
Values are expressed as mean, with standard error in parentheses; * Mann-Whitney U test; PE = polyethylene; XLPE = highly crosslinked polyethylene.