Proponents argue PCL retention better restores normal knee kinematics and proprioception. However, degenerated PCLs may not function properly if retained. One randomized trial found worse flexion with retention versus sacrifice or substitution, suggesting overconstraint. Another showed equivalent function between retention and sacrifice groups.
Sacrificing the PCL can facilitate bony resection, soft tissue balancing, and deformity correction. Concerns include altered kinematics and increased implant stresses. However, multiple studies demonstrate well-functioning knees despite PCL removal. Stability differences are not clinically significant.
Posterior-stabilized implants are designed to mimic PCL function through a tibial post and femoral cam. Benefits include facilitating flexion and anteroposterior stability. However, kinematics still differ from the native knee. Outcomes are similar to PCL retention and sacrifice techniques.
Partial PCL release may improve flexion in tight knees. However, subsequent scar tissue formation can cause recurrent tightness. One study found worse results with release versus retention or substitution. Complete release risks destabilization.
In summary, PCL retention, sacrifice, and substitution techniques yield comparable outcomes. Ligament state, surgical goals, and implant design help guide management. More research is needed on proprioception and long-term implant wear.