The PCL significantly affects the functional outcome of total knee replacement

Controversy exists over the consequences of PCL retention in total knee replacement. The present study was performed to test the hypothesis that patients receiving a PCL-retaining prosthesis have no difference in functional outcome compared to those receiving a cruciate-sacrificing, posterior stabilized design. Forty-nine patients were enrolled in the study with IRB approval. All patients underwent a TKR performed by a single surgeon using the same implant design with either a PCL-retaining tibial insert or a posterior stabilized insert. At a minimum follow-up of 1 year, each patient completed a self-administered, validated “Knee Function Questionnaire.” Patients also completed the SF-36 and the AKS questionnaires. No statistically significant differences were reported between the two groups using the traditional measures of function following total knee replacement, including overall satisfaction with surgery although patients with PS knees did report greater functional limitations in squatting, kneeling, and gardening. Substitution for the PCL with a spine and cam mechanism does not fully restore the functional capacity of the intact PCL, particularly in high demand activities which involve deep flexion.