Recent Evolution of Cruciate Ligament Surgery of the Knee

Correspondence to: Young-Bok Jung, MD Emeritus Professor, Chung Ang University, Seoul Joint Center, Hyundae General Hospital, 663 Janhyn-ri, Jinjeop-eup, Namyangju 472-865, Korea Tel: +82-31-574-9119, Fax: +82-31-874-3779 E-mail: [email protected] There have been many recent improvements in cruciate ligament surgery of the knee. The anterior cruciate ligament (ACL) reconstruction has been changed from isometric placement to anatomical position. Anatomical ACL reconstruction is currently considered more eff ective in the recovery of biomechanical and kinematic function of the knee joint, reduction of rotatory instability, and prevention of secondary degenerative arthritis. In the past 20 to 30 years, a relatively vertical femoral tunnel was placed at the 11 o’clock position and a relatively posterior tibial tunnel was created at the center of the insertion site of the posterolateral bundle (PLB) to avoid graft impingement by the femoral anterior intercondylar roof during ACL reconstruction. Th is was performed from the tunnel in the tibial PLB to that in the femoral anteromedial bundle (AMB), creating a mismatch. Some recent studies have shown that single-bundle reconstruction using an anatomical center between the AMB and the PLB is comparable to double-bundle reconstruction in terms of biomechanical benefits. There is still controversy over comparative advantages between anatomical double-bundle reconstruction and single-bundle reconstruction. Some studies suggest that double-bundle reconstruction is more eff ective in restoring biomechanical function of the knee than single-bundle reconstruction whereas others document there are no clinical diff erences between the procedures. However, double-bundle reconstruction is technically more diffi cult to perform in patients with small stature and requires longer operative time. In these patients, the tunnel is often placed at the center of the tibial and femoral footprints of the ACL (anatomical reconstruction), but transtibial femoral tunnel drilling becomes almost impossible with this technique. Th us, a far anteromedial portal (accessory anteromedial) that is approximately 2 cm medial to the anteromedial portal and just above the meniscus is created as a working portal for femoral tunnel drilling. One of the challenges during this procedure is to obtain adequate visualization for tunnel drilling with the knee in 120 flexion. For enhanced visualization, an endo-reamer placed in a transparent plastic tube can be used for femoral tunnel drilling, which also facilitates joint irrigation and bone debris removal. Making an outflow in the high anteromedial area prior to knee flexion can also be helpful for obtaining proper visualization during surgery. Alternative options include creating a femoral tunnel through an incision in the posterolateral aspect of the femur or the outside-in femoral tunnel drilling using a reverse reamer or a fl ip cutter (Arthrex Inc., Naples, FL, USA), which does not necessitate 120 fl exion of the knee during surgery. On the other hand, some recent reports showed that an ACL injury can heal spontaneously even when the ACL fibers are torn if the synovial sheath that surrounds the damaged ACL is preserved relatively intact and anterior displacement of the knee is avoided for a certain period of time. In addition, remnant-preserving techniques in ACL reconstruction would result in the recovery of proprioception and remnant tensioning techniques, albeit more technically challenging and time-consuming, could provide good results. I observed that the ACL remained attached to the femur and tibia in 27.4% (90 in 324) of the patients in my clinic and thought that remnant-preserving techniques could be effective even when the damaged ACL is attached to the posterior cruciate ligament (PCL) through separation and pull-out suture. PCL reconstruction received less coverage in the literature in the past and was thought nearly a decade be-