Jumbo cup in hip joint renovation may cause the center of rotation to increase

Figure 2 The center of this circle was assumed to be the hip joint center[11]. After the left revision total hip arthroplasty obtained anteroposterior pelvic radiographs with a giant cup showed that the revision cup was larger than the contralateral acetabulum. The teardrop line intersects the lower edge of the cup, indicating that jumbo cup is placed in planned position that the lower edge of cup at the lower edge of acetabulum. The medium line is parallel to the lower edge of teardrop line and intersects center of right hip. The upper end line parallel to the tear drop line intersects center of the left giant cup. The distance (arrows) between two lines is labeled as elevated height of rotating center occurred in applying jumbo cup.