The anterior cruciate ligament (ACL) is one of the four major ligaments of the knee. Twisting or pivoting movements are what typically cause the ACL to strain or tear.
Ligaments are strong, dense structures made of connective tissue that help stabilize a joint. The ACL connects the femur bone to the tibia bone. The function of the ACL is to provide stability to the knee with twisting movements and minimize stress across the knee joint.
ACL tears occur in athletes participating in cutting and pivoting sports such as basketball, football, soccer, and skiing. The athlete typically feels a “pop” or a tearing sensation and experiences swelling within six hours of the injury. The most common injury associated with ACL tears is a meniscus tear. It is well recognized that there is an increased incidence of ACL tears in female athletes.
ACL strains can sometimes be treated with physical therapy and muscle strengthening, however, most complete tears require surgery in active patients. ACL surgery involves completely removing the torn ligament and reconstructing the torn ACL with tissue from somewhere else (graft). The most common grafts used to reconstruct a torn ACL are the patellar tendon, hamstring tendons, or cadaver tissue (allograft). Each graft offers specific advantages and disadvantages, so it is important to understand the differences.
Arthroscopic ACL Reconstruction
Modern ACL reconstruction involves making a new ACL out of graft material obtained either from the patient with minimally invasive surgical methods or from a cadaver. After the tissue is cleaned and prepared into the ideal length and diameter, an arthroscope is used to prepare the knee to receive the graft.
Using the arthroscope, the knee is cleaned and any associated cartilage tears are addressed. Tunnels are precisely created in the tibia and the femur. After the tunnels are created and carefully contoured to receive the graft, the graft is passed into the knee joint through the tibial tunnel and then up into the femoral tunnel. Final fixation of the graft is then performed using any of a number of devices to solidly lock the graft into the tunnels.