Fig. 3From: Computer simulation of optimal lipped polyethylene liner orientation against prosthetic impingementa Flexion was simulated and was observed from side. b Impingement on the liner of the cup during flexion was detected visually from a horizontal view and the flexion angle was recorded once impingement being visible. The red block showed the impingement area and the red arrow pointed to the contact between the femoral neck and the cup linerBack to article page