Pelvic Area Extension Measurements for Four Types of Lumbopelvic Balance Using Three Different Methods

"The pelvic extension reserve (°) is measured via goniometry.~The goniometric measurements will be taken once by an investigator on all subjects and once by a different investigator on half of the subjects (with balanced distribution of morphotypes)."

"The pelvic extension reserve (°) is measured using photography.~Photographic measurements will be performed twice one investigator and 1 time by a different investigator (total of three measurements)."

"The pelvic extension reserve (°) is measured using the imaging system EOS.~Five X-rays will be made for each volunteer on the EOS system. The first is a frontal shot in a bipedal position, reference snapshot for verifying the absence of spinal deformity or hip pathology. The second and third are profile shots, one on the left and one on the right, whole body, bipedal position; serving as a reference picture. The fourth is profile shot, whole body, with the left hip in hyperextension. For maximum left hip hyperextension, the right leg rests on a step of varying height, and the hip is maximally flexed. The fifth is a profile shot, full body, with the right hip in hyperextension. For a maximum right hip hyperextension, the left leg rests on a step of varying height, and the hip is maximally flexed."