摘要
Malrotation following Total Knee Arthroplasty (TKA) is directly related to poor outcome. Knowledge of the rotational axes (torsion) and angles is therefore important. The aim of the study was to determine whether an association existed between the Femoral Anteversion Angle (FAA) Posterior Condylar Angle (PCA) and the Inferior Condylar Angle (ICA) in individuals. A CT scan of 50 (25 paired) cadaver femora was made. The FAA, PCA and ICA were measured. Statistical analysis of comparative relationships between these different angles was examined by calculating Pearson correlation coefficients and a paired t-test. The mean FAA, PCA and ICA for the whole group were respectively 11.7° (range 0 - 32, SD 8.2), 5.18° (range 0 - 12, SD 2.4) and 4.4° (range 0 - 10, SD 2.1). A correlation of 0.82 (p = 0.01) of the FAA was found between left versus right. For the overall group a correlation coefficient between the PCA of the left and right femur was r = 0.59, p = 0.01. The Pearson correlation between the FAA and PCA in the whole group was r = 0.27, p = 0.06. In females this was r = 0.54 (p = 0.03). Although the difference of the mean ICA and PCA was very small (0.7°), there was no correlation between these angles (r = 0.14, p = 0.23). In conclusion, one should be aware that, considering the weak correlation of the FAA and PCA, an individual rotational variation exists. Furthermore, no correlation was found between the PCA and ICA. Therefore, for now, this angle cannot be assumed to be helpful in TKA. A more individual approach in total knee arthroplasty seems essential for future TKA.
Malrotation following Total Knee Arthroplasty (TKA) is directly related to poor outcome. Knowledge of the rotational axes (torsion) and angles is therefore important. The aim of the study was to determine whether an association existed between the Femoral Anteversion Angle (FAA) Posterior Condylar Angle (PCA) and the Inferior Condylar Angle (ICA) in individuals. A CT scan of 50 (25 paired) cadaver femora was made. The FAA, PCA and ICA were measured. Statistical analysis of comparative relationships between these different angles was examined by calculating Pearson correlation coefficients and a paired t-test. The mean FAA, PCA and ICA for the whole group were respectively 11.7° (range 0 - 32, SD 8.2), 5.18° (range 0 - 12, SD 2.4) and 4.4° (range 0 - 10, SD 2.1). A correlation of 0.82 (p = 0.01) of the FAA was found between left versus right. For the overall group a correlation coefficient between the PCA of the left and right femur was r = 0.59, p = 0.01. The Pearson correlation between the FAA and PCA in the whole group was r = 0.27, p = 0.06. In females this was r = 0.54 (p = 0.03). Although the difference of the mean ICA and PCA was very small (0.7°), there was no correlation between these angles (r = 0.14, p = 0.23). In conclusion, one should be aware that, considering the weak correlation of the FAA and PCA, an individual rotational variation exists. Furthermore, no correlation was found between the PCA and ICA. Therefore, for now, this angle cannot be assumed to be helpful in TKA. A more individual approach in total knee arthroplasty seems essential for future TKA.
