Femoral neck angle
Commonly the femoral neck angle is the most known individual difference. A femoral neck angle is usually classified into 3 categories: coxa valga (a more vertical angle inserting into the pelvis), coxa vara (a more horizontal angle inserting into the pelvis) and what is considered a more “normal” angle of roughly 40-50 degrees. The funny thing is the normal angle occurs with less frequency than the combined angles of coxa vara and valga, meaning it’s somewhat more rare to see.
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The femoral neck anteversion (FNA) can be defined as the angle formed by the femoral condyles plane (bicondylar plane) and a plane passing through the center of the neck and femoral head1,2 (Figure-1). If the axis of the neck inclines forward to transcondylar plane the angle of torsion is called anteversion,
if it points posterior to the transcondylar plane it is called retroversion and if the axis of neck is in the same line of transcondylar plane it is known as neutral version (Figure-2).
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