Effect of cementless acetabular component orientation, position, and containment in total hip arthroplasty for congenital hip disease.

We evaluated the effect of the inclination angle, position, and containment of 53 cementless cups inserted in patients with congenital hip disease (CHD), after a minimum of 10 years of follow-up. The polyethylene wear rate was significantly greater when the cup was placed in more than 45° inclination (P=.045) or if the cup was placed lateral to the teardrop position by more than 25 mm (P=.001). Aseptic loosening of the femoral component was significantly greater when the cup was placed more than 25 mm superiorly to the teardrop (P=.049). Cup placement of more than 25 mm lateral to the teardrop affected significantly periacetabular osteolysis (P=.032). In CHD cases, it is preferable to avoid excessive vertical inclination, lateral, and superior placement of cementless cups in an attempt to obtain better containment.