New technique for ACL repair

BACKGROUND:   The anterior cruciate ligament (ACL) is one of the major ligaments in the knee.  Ligaments are strong bands of tissue that connect bones.  The ACL is one of two ligaments that cross in the middle of the knee.  It connects the femur to the shinbone (the tibia) and helps stabilize the knee joint.  ACL injuries commonly occur during sports that involve sudden changes in direction, like soccer, basketball, football, and volleyball.  A torn ACL cannot be sewn back together. Therefore, the ligament is replaced with a piece of tendon from another part of your leg or from a deceased donor.  The surgery is done through tiny incisions around the knee joint and a narrow, fiber-optic scope is used to guide the ACL graft.  (Source: www.mayoclinic.com)


WHEN TO GET ACL RECONSTRUCTION:  Most ACL injuries happen during fitness activities and sports.  The ligament can tear when a person slows suddenly to change direction or pivot, overextending or twisting the knee.  However, not everyone who tears an ACL requires ACL reconstruction.  Sedentary people who have an ACL injury recover well with physical therapy and conservative treatments.  Doctors might recommend ACL reconstruction if:


  • More than one ligament or the cartilage in the knee is injured.
  • You are an athlete and want to continue playing your sport, especially if the sport involves cutting, jumping, or pivoting.
  • You are active and young.
  • The injury is causing the knee to buckle during everyday activities, like walking up stairs. (Source: www.mayoclinic.com)


NEW TECHNOLOGY:  The drilling of the femoral tunnel with the transtibial (TT) technique is widely used in none-patellar tendon bone (BPTB) ACL reconstruction and studies suggest higher knee stability with the use of the anteromedial portal.  The autograft or allograft arthroscopic single-bundle (SB) is a very popular technique for ACL reconstruction.  The most popular femoral drilling method was the two-incision technique, in which the femoral tunnel is created outside-in.  The TT technique was the subsequent method of choice for the femoral tunnel placement.  The TT drilling method was adopted to reduce operative time and surgical morbidity.  However, recent studies show that the SB TT ACL reconstruction places the graft in a non-anatomical femoral insertion site, which is the most common cause of ACL reconstruction failure.  The anatomical ACL reconstruction emerged as a potential solution for non-anatomical reconstructions.  It better restores knee stability than other procedures.  Other advantages include:  the formal and tibial tunnels are placed independently of each other; the femoral tunnel can be drilled with knee inhyperflexion reducing the risk of posterior wall blow out; the femoral tunnel is placed more anatomically on the ACL femoral insertion site; the AMP technique allows for easy augmentation by preserving the remaining ACL fibres; the easy parallel placement of the interference screw to the bone plug with no lateral incisions; the tunnel placement is independent of graft type; and it is flexible enough so that SB, double-bundle, and revision procedures may be easily performed.  However, limitations can include:  the femoral tunnel needs to be created with 110-120 degrees of knee flexion to avoid injury to posterior "blow-outs"; several graft fixation techniques require guide instruments designed for TT insertion and may not be appropriate for the AMP technique; and visualization is challenging when a leg holder is being used.  (Source: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2903180/)



Tony Nguyen, MD

Orthopedic Surgeon in Sports Medicine and Trauma

The CORE Institute