There is no consensus as to whether to use a posterior cruciate ligament (PCL) retaining design or a posterior-stabilized design for total knee arthroplasty. The objective of this study was to establish the difference in functional, clinical, and radiological outcome between retention and removal of the PCL. We conducted a search in Medline, EMBASE, the Cochrane database, and Current Contents, along with reference checks and citation tracking. Randomized controlled trials were selected and methodological quality was assessed with the van Tulder and Jadad checklists by 2 independent reviewers. We found 8 randomized controlled trials. 2 treatment options were compared against PCL retention: PCL removal without post and cam mechanism (2 studies), and posterior-stabilized design (5 studies). 1 study included all 3 options. Range of motion was found to be 8 degrees higher (105 degrees vs. 113 degrees ) in the posterior-stabilized group compared to the PCL retention group (p = 0.01, 95% CI (1.7, 15)). These results should be interpreted with caution, as the methodological quality of the studies was highly variable. Suggestions are given to improve future research on this specific aspect of knee arthroplasty.