Technique of the measurement of the hip joint range of rotation. Patient in prone position, hips in neutral position, knees in 90° flexion. In spontaneous position there is an obliquity of the pelvis, masking asymmetry of rotation, and detected with the scoliometer placed over the posterior superior iliac spines (A). Asymmetry of the range of internal rotation: left hip = 25°, right hip = 55° (B). Asymmetry of the range of external rotation: left hip = 30° (C), right hip = 5° (D). The sum of rotation range is 55° for the left and 60° for the right hip. Transposition of the sector of rotation towards internal rotation may be diagnosed within the right hip, instead of claiming the limitation of hip motion. The mid-point of rotation is 2.5° for the left and 25° for the right hip. Therefore there is a static rotational offset of the pelvis of 22.5°, directed to the right side.