Retention of the posterior cruciate ligament in total knee arthroplasty

The importance of the preservation of the posterior cruciate ligament in total knee arthroplasty is analyzed from a biomechanical, clinical, and functional standpoint. Using clinical and radiographic criteria, the authors assess posterior cruciate ligament validity in a selected group of 31 of 45 total knee arthroplasties (PCA prosthesis) reviewed at least 18 months after the operation. Sixty-eight percent of the replaced knees, which were divided into two groups on the basis of preoperative deformity, had a functional posterior cruciate ligament. In view of these results the authors are satisfied with the prosthetic model they adopted, which was designed not only to preserve the posterior cruciate ligament, but also, by virtue of its special shape, to compensate in the event of ligament insufficiency.