Surgical reconstruction for a torn ACL or anterior cruciate ligament continues to evolve with newer techniques designed to improve results and better reproduce the normal anatomy of the ACL. This is a special interest of Dr. Burris and was a focus of his additional fellowship training in Sports Medicine at the University of Kentucky.
Anterior cruciate ligament ruptures most commonly occur as the result of a noncontact injury during “ACL dependent” sports such as soccer, football, basketball, and skiing. This is a season ending injury for athletes. While surgery for the torn ACL is not necessary for all patients, it is typically recommended for athletically active individuals.
Results of ACL reconstruction have in general been considered to be very good. However, results have more recently been questioned for certain subpopulations such as young and elite level athletes that may place higher demands on the surgically reconstructed knee. Particular issues that have arisen in an effort to improve our results include modifying surgical techniques and determining the best graft options for reconstructing the new ligament.
Anatomic ACL Reconstruction
Recent modifications have been made to the classic technique of arthroscopic ACL reconstruction. The main focus has been changing the position of the bone tunnel drilled through the femur or thigh bone, allowing the new ACL to be placed in its normal anatomic location. The theoretical advantage of the newer technique is that it will provide better rotational control of the knee during sporting activities, leading to less failures and better knee function. This is the preferred technique of Dr. Burris.
The “double bundle” ACL is another newer technique which uses two separate ligaments to reconstruct the ACL. This technique is currently being used by a limited number of orthopaedic surgeons as results and experience are obtained. These two techniques are often referred to as “anatomic ACL reconstruction.”
5 Strand Hamstring Graft
This is another recent advance in ACL surgery. The diameter or size of the graft used has been shown to be one of several factors which can affect the rate of re-tearing the ACL. Hamstring tendons are commonly used to reconstruct the ACL and most commonly as a doubled over 4 strand graft. The 5 strand hamstring graft produces a larger diameter graft from the same hamstring tendons which may ultimately decrease the risk of re-injury. Dr. Burris is currently one of few orthopedic surgeons in the region who performs this technique.
Graft OptionsGraft options to build a new ACL include grafts taken from your own leg called autografts and grafts taken from a cadaver called allografts. The two most common autografts include a portion of the patellar tendon with attached pieces of bone and two of the smaller hamstring tendons, the gracilis and semitendinosis. Results are very for good for both of these grafts. The patellar tendon graft however has been associated with a higher incidence of pain in the front of the knee.
Allografts are commonly used in revision surgery situations where previous tissue may have already been taken from the leg. It has also become a popular option for first time or primary ACL reconstructions. The main advantage of allografts is decreased pain in the early postoperative period. A disadvantage of allograft tissue is that it takes a significantly longer time to heal in as compared to an autograft. Current information is also beginning to show higher failure rates with allografts, in particularly when used in younger and higher demand athletic patients. Caution should be used when selecting allograft tissue for a young, high demand athlete. Graft options and deciding what graft is right for you should be discussed with your surgeon pre-operatively.