Correct alignment and rotation can be checked with intraoperative imaging. The latero-medial projection is used and the whole bone, including the proximal and distal joints, must be visible.
If the femur is properly aligned in the transverse plane, about 1/3 of the femoral head should be visible cranially to the cranial femoral cortex (Image A). Image B shows excessive internal rotation and C shows excessive external rotation of the distal femur.
Comparison with the contralateral unaffected limb can be useful.