Table 3 Tibio-femoral mechanical angle malalignment (cTFmA)
Author | RAQ criteria for radiological bias | Association between malalignment and worse outcome | Sample size | Alignment data | Findings |
|---|---|---|---|---|---|
Parratte et al. (2010) | Low risk | No | 398 | 292 knees classed as mechanically aligned 0° ± 3. 10 knees in the outlier group (beyond 0° ÷ 3° | 15.4 % revision rate in the mechanically aligned group. 13 % in the outlier group (p = 0.88). No association between malalignment and revision |
Bonner et al. (2011) | Low risk | No | 458 | 372 knees were classified as mechanically aligned (0° ± 3°). 86 knees were within the malaligned group | 33 revisions for aseptic loosening. Kaplan–Meier survival analysis showed a weak tendency towards improved survival with restoration of a neutral mechanical axis, but this did not reach statistical significance (p = 0.47) |
Magnussen et al. (2011) | Low risk | No | 553 | 181 patients were in varus alignment, 352 were in neutral alignment and 20 were in valgus alignment | No statistically significant difference in revision rates between the three groups (p = 0.15) |