Fig. 1

Measurement of femoral head penetration into the liners (measured on reconstructed CT). One line is drawn from the superior to the inferior edge of the acetabular component. The distances from the superior margin of the acetabular component to the femoral head and from the inferior margin of the acetabular component to the femoral head were measured. a A 37/F patient underwent THA with CoC bearing for right AVNF, the femoral head penetration was measured on reconstructed CT at postoperative 7 years. b A 69/F patient underwent THA with CoXPE bearing for left AVNF; the femoral head penetration was measured on reconstructed CT at postoperative 8 years