“…Hüfner et al [7] found inexperienced orthopaedic surgeons accurately applied Letournel's classification for acetabular fractures in only 11% of cases. In 2009, Prevezas et al [18] proposed guidelines to increase the reliability and validity of Letournel's classification. They suggested an algorithm for evaluating pelvic radiographs based first on examination of basic lines (ilioischial, iliopectineal), then further subdivision into Letournel's 10 fracture patterns based on examination of four anatomic landmarks (teardrop, anterior and posterior acetabular rim, acetabular dome), the integrity of the obturator foramen, the level of fracture lines, and the presence or absence of a spur sign.…”