69 patients (90 knees) scheduled for total knee arthroplasty (TKA) with a highly conforming, mobile-bearing insert were randomized to have the posterior cruciate ligament (PCL) either retained for resected during surgery. The purpose was to determine if PCL preservation led to better kinematic and clinical outcome. Intraoperative kinematic measurements indicated that PCL-preserving TKA was associated with greater anterior translation and more varus femoral rotation than PCL-sacrificing TKA. Clinical outcome was similar between groups at a minimum of 2 years follow-up. Based on the results, PCL resection is suggested in highly conforming mobile-bearing TKA.