Due to great variability fixed HKS angle for alignment of the distal cut leads to a significant error in coronal TKA orientation
Maurin Lampart, Henrik Behrend, Lukas B Moser & Michael T Hirschmann
The HKS angle was not constant at 7° but averaged 6°, and ranged from 2.5° to 9°. The FMA angle was on average 93° but varied more than 20°, ranging from 75° (varus) to 104° (valgus). The mean HKA ± SD was - 3.4° ± 5.7° (range - 23.0° to 15.0°). The mean HKSSD was 5.6° ± 0.9° (range 2.5°-8.8°). The mean FMASD was 92.6° ± 2.8° (range 75.2°-103.5°). The Pearson correlations of all measured angles are presented in Table 1. HKS significantly correlated negatively with HKA and FMA (p < 0.001). FMA and HKA were strongly correlated with each other (p < 0.0001). Considering the HKS angle as a constant angle can induce a deviation of up to 5° with respect to an orthogonal distal femoral cutting objective. The great variability of the FMA angle implies that the FMA seems more relevant than the HKS angle to define the strategy of realignment of the lower limb. However, then patient specific instrumentation has to be used to precisely transfer the planning to the surgical technique. Having the aim of a more personalized TKA alignment in mind the individual constitutional knee phenotype should be taken into account.
|citation||Lampart M, Behrend H, Moser L B, Hirschmann M T. Due to great variability fixed HKS angle for alignment of the distal cut leads to a significant error in coronal TKA orientation. Knee Surg Sports Traumatol Arthrosc 2018;.|
|type||journal paper/review (English)|
|date of publishing||30-06-2018|
|journal title||Knee Surg Sports Traumatol Arthrosc|