Fig. 4

According to the postoperative X-ray, the drawing tool (Photoshop) was used to evaluate the unequal length of the lower limbs by the CFR-T-LT method. An initial reference line is drawn between the centers of femoral rotation, and two further lines are drawn parallel to it. The first at the level of the most inferior part of the acetabular teardrop to give measurement C, which corresponds to any inequality (C^A-C^N) due to the position of the cup. The second is at the level of the center of the lesser trochanter to give measurement S, which corresponds to inequality (S^A-S^N) due to position of the stem. The sum of the two is measurement O which corresponds to the overall leg length inequality (O^A-O^N)