Table 3.
Reproducibility of femoral angular measurement results of various parallel (0°) and varying off-z-axis (15° and 45° deviated) double oblique positioning of the femurs on the CT table in the gantry during scanning to test for the independency of femoral positioning.
|
Femurs: n = 13 Positioning: Three times CT-scans: 39 |
Intra-observer agreement | Inter-observer agreement | ||||
|---|---|---|---|---|---|---|
| Angle | Mean | Standard deviation | Coefficient of variation for repeated measurements (%) | Mean | Standard deviation | Coefficient of variation for repeated measurements (%) |
| Femoral torsion angle-neck center (FTA-NC) | 17.913 | 0.699 | 3.899 | 18.509 | 2.49 | 13.454 |
| Femoral torsion angle-neck base center (FTA-NBC) | 26.931 | 0.394 | 1.464 | 26.537 | 1.459 | 5.499 |
| Femoral neck inclination angle-neck center (FIA-NC) | 124.769 | 0.4891 | 0.392 | 126.26 | 4.011 | 3.177 |
| Femoral neck inclination angle-neck base center (FIA-NBC) | 140.912 | 0.936 | 0.664 | 141.055 | 2.012 | 1.426 |
| Femoral varus or valgus angle total-distal (FVA-td) | 180.142 | 0.376 | 0.209 | 179.103 | 2.628 | 1.467 |
| Femoral varus or valgus angle proximal-distal (FVA-pd) | 179.264 | 0.396 | 0.221 | 178.987 | 2.338 | 1.306 |