Fig. 4From: A comparative study of flat surface design and medial pivot design in posterior cruciate-retaining total knee arthroplasty: a matched pair cohort study of two yearsClinical appearance (a) and X-ray (b) in a patient of FINE knee group with 140 degrees of flexion. You can see enough roll back but bone-implant impingement between the posterior femoral condyle and the posterior part of tibial plate and the polyethylene, indicating the limit of deep flexionBack to article page