Fig. 6

Location of the ilioischial line on the medial acetabular wall. The line connecting the anterior and posterior margins of the medial acetabular wall is divided into four equal parts (i.e., zones 1–4) from the anterior to the posterior point. A perpendicular line is drawn through all the zones and the medial acetabular wall. In this example, the center of the medial acetabular wall that overlaps with line α is located in zone 3