Higher rates of fully preserved posterior cruciate ligament in total knee arthroplasty using a double tibial cut: a prospective randomized controlled trial

PurposeIn cruciate retaining total knee arthroplasty, posterior cruciate ligament damage may occur during tibial cutting. A prospective randomized study was conducted to investigate whether a novel tibial cutting technique was more effective than the currently used techniques.Materials and methodsPatients undergoing cruciate retaining total knee arthroplasty were recruited in a prospective, randomized, controlled trial. In 25 patients (group 1) the tibial cut was performed using a double tibial cut technique; in 25 (group 2) and 25 (group 3) patients, the bone island and en bloc resection techniques were performed, respectively. Posterior cruciate ligament integrity and femoral rollback were assessed at the end of surgery. The Oxford Knee Score, WOMAC score and range of motion were assessed postoperatively.ResultsPosterior cruciate ligament was completely preserved in 92% of patients in group 1 and in 64% in group 2 and 3, respectively (p = 0.03). The Oxford Knee Score and WOMAC scores did not differ between groups (p = 0.4). The mean knee flexion was 126.4 degrees, 121.5 degrees and 123.9 degrees in groups 1, 2 and 3, respectively (p = 0.04). The femoral rollback at 120 degrees flexion was 80.7%, 72.2% and 75.4% in groups 1, 2 and 3, respectively (p = 0.01).ConclusionsThe double cut technique preserves the posterior cruciate ligament at significantly higher rates than the bone island or en bloc resection techniques. Better posterior cruciate ligament preservation may improve the femoral rollback and knee flexion.Level of evidenceProspective randomized controlled trial, Level I.