Coxa valga and antetorta increases differences among different femoral version measurements

Abstract

Aims To evaluate how abnormal proximal femoral anatomy affects different femoral version measurements in young patients with hip pain. Methods First, femoral version was measured in 50 hips of symptomatic consecutively selected patients with hip pain (mean age 20 years (SD 6), 60% (n = 25) females) on preoperative CT scans using different measurement methods: Lee et al, Reikerås et al, Tomczak et al, and Murphy et al. Neck-shaft angle (NSA) and α angle were measured on coronal and radial CT images. Second, CT scans from three patients with femoral retroversion, normal femoral version, and anteversion were used to create 3D femur models, which were manipulated to generate models with different NSAs and different cam lesions, resulting in eight models per patient. Femoral version measurements were repeated on manipulated femora. Results Comparing the different measurement methods for femoral version resulted in a maximum mean difference of 18° (95% CI 16 to 20) between the most proximal (Lee et al) and most distal (Murphy et al) methods. Higher differences in proximal and distal femoral version measurement techniques were seen in femora with greater femoral version ( r > 0.46; p < 0.001) and greater NSA ( r > 0.37; p = 0.008) between all measurement methods. In the parametric 3D manipulation analysis, differences in femoral version increased 11° and 9° in patients with high and normal femoral version, respectively, with increasing NSA (110° to 150°). Conclusion Measurement of femoral version angles differ depending on the method used to almost 20°, which is in the range of the aimed surgical correction in derotational femoral osteotomy and thus can be considered clinically relevant. Differences between proximal and distal measurement methods further increase by increasing femoral version and NSA. Measurement methods that take the entire proximal femur into account by using distal landmarks may produce more sensitive measurements of these differences. Cite this article: Bone Jt Open 2022;3(10):759–766.

Femoroazetabuläres Impingement beim Jugendlichen und Adoleszenten

“…Eine weitverbreitete Methode, die auch in den Kliniken der Autoren zur Anwendung kommt, ist die Methode nach Murphy (Messung auf Höhe des Trochanter minor; Abb. 3 ), da sie den Rotationsfehler auch bei Hüften mit exzessiv erhöhter Femurtorsion und Valgusdeformitäten am genauesten abbildet [ 28 ].…”

Präoperative MRT-Bildgebung bei Hüftdysplasie

“…Diese Unterschiede können beim selben Patienten bis zu 20°b etragen [57]. Diese Unterschiede sind vor allem bei Patienten mit erhöhter femoraler Antetorsion und bei Valgusdeformitäten zu beachten [59]. Die Normwerte der jeweiligen Messmethoden sollten beachtet werden (.…”