Surgical Intervention Options to Restore Natural Knee Kinematics
The Knee is a six degree of freedom joint that utilizes the meniscus, ligaments, tendons and muscles to stabilize locomotion for activities of daily living. The joint behaves like a screw-home mechanism where the medial compartment is highly constrained and stable, whereas the lateral compartment is allowed to rotate and translate to allow activities that require higher flexion angles of up to 155 degrees. Damage to the cartilage and cruciate ligaments can often disrupt this motion. There are several surgical approaches that can be taken to restore the natural knee motion. Total Knee Replacement is the most common option, and often utilizes cementing to fix the knee implant to the bone surface. More recently, the unicondylar knee replacement, which more frequently replaces the more prevalent medial damaged cartilage, is utilized. Additionally, bicruciate knee replacements have been introduced, which serves to preserve the ACL. It is important to note that some of the new generation implants are investigating the use of a cementless approach that encourages bone ingrowth to achieve superior fixation. This talk will provide a brief history and design rationale, as well as the achievements and challenges for the various combinations of surgical interventions to restore the natural knee kinematics.