Table of Contents
How do you calculate femoral anteversion on CT?
Measure the Condyle-Horizontal Angle (CH). Calculate the angle of the Neck relative to the Condyles (NC=NH-CH). ←For the example to the left, the Neck-Horizontal angle=30°, the Condyle-Horizontal=10°, thus the relative angle between the Femoral Neck and Condyles =20°. This is the Femoral Anteversion angle.
How is femoral rotation measured in CT?
1—Single-slice axial CT anteversion measurement. A, Using axial images to measure anteversion, femoral neck angle is measured on single image that best shows neck axis. B, Condylar angle is measured by drawing line across posterior margin of femoral condyles, to correct for rotation of femur.
How do you assess femoral anteversion?
Femoral anteversion is diagnosed through observation and examination. A specialist will observe your child to see if the toes and/or kneecaps turn inward as he or she walks. The physical exam is typically conducted with the child laying down. This position helps determine the degree of the femur’s internal rotation.
What do you do for femoral anteversion?
A surgery called a femoral derotational osteotomy may be done to correct femoral anteversion. The surgery involves separating the femur bone and rotating it to the correct position. The pieces are then held in place by a rod that is inserted inside the bone.
What causes femoral retroversion in adults?
The exact cause of femoral retroversion is unknown. Femoral retroversion is often a congenital condition, meaning it is present from birth and develops in the womb.
How is the femoral anteversion angle measured in CT scans?
Twenty patients (20 hips) with unilateral non syndromic DDH were studies. CT scans were performed using a 16 slice CT scanner to measure the femoral anteversion angle (FAVA) using 2D & 3D techniques. Findings were correlated with the intra operative measurements.
What kind of osteotomy is performed for femoral anteversion?
It is often easiest to generate a relatively thick MIP at both levels if using CT. In many patients, there is no need for individual correction of an abnormal femoral anteversion. In patients with severe femoral anteversion or retroversion, a subtrochanteric rotational osteotomy of the femur may be performed 7.
Which is the anterior orientation of the femur?
In most cases, the femoral neck is oriented anteriorly as compared to the femoral condyles. In the case of posterior orientation, the term femoral retroversion is also applied. Actually describing the intrinsic rotation of the femur over its length from the hip to the knee, femoral anteversion may also be more aptly termed femoral antetorsion.
What is the relationship between femoral anteversion and FAI?
Moreover, it has been shown that abnormal femoral anteversion can contribute to the development of femoroacetabular impingement (FAI) ; reduced femoral anteversion is associated with cam-type FAI 6.