Most athletes who injure their anterior cruciate ligaments (ACLs) want to rehab and get back on the field or court. Many do but some never seem to get back to their top form. Others have a stable knee but one that develops arthritis early in life. So the search is on for a better way to repair this knee ligament.
In this article surgeons from around the world (Japan, Greece, and the United States) discuss the use of double-bundle ACL repair. They compare the results with the current, standard single-bundle repair.
Double-bundle refers to how the tendon graft is split into two parts. One-half replaces the front (anterior) half of the ACL. The second half replaces the back or posterior portion of the ACL. This mimics the natural anatomy of the ACL.
The double-bundle repair is a new technique used only by specialists at this time. It’s a more difficult operation to perform. Studies have not proven its value yet over the standard single-bundle method.
The key benefit to the double-bundle method is the control it gives over tibial rotation. The natural (undamaged) ACL allows the lower leg bone (tibia) some movement when the foot is planted and the player pivots or shifts the knee in another direction. A single-bundle repair doesn’t allow the knee this extra rotation.
Using the double-bundle ACL repair appears to restore normal kinematics (motion) of the knee needed for high-level athletes. The hope is that this improved rotational stability will prevent the early degenerative changes that lead to arthritis in many single-bundle repairs. Studies are needed to compare the long-term results of single- versus double-bundle repairs.