Anterior cruciate ligament reconstruction with double bundle technique
Arthroscopic reconstruction of the cruciate ligaments with autologous tendon grafts is an established method of choice for the treatment of anterior cruciate ligament rupture. In the operation, the surgeon replaces the ruptured anterior cruciate ligament with a tendon graft, usually with autologous tendon of semi membranous and gracilis muscle, which is taken during the surgery from the back of the thighbone. The aim of the procedure is to improve knee stability and reduce the risk of delayed complications of chronic knee instability such as repeated meniscus injuries and wear and tear of cartilage. Arthroscopic operative technique has many advantages over traditional open reconstruction of the cruciate ligaments: it allows a much more precise positioning of the tendon graft in the joint, it preserves the surrounding soft tissues, importantly lower is the risk of perioperative infections of joint, and there is less postoperative pain. For a good outcome of the treatment, after the reconstruction of the anterior cruciate ligament, the key is also an individual postoperative rehabilitation of good quality that lasts up to 6 months after surgery.
Course of arthroscopic reconstruction of anterior cruciate ligament
This type of surgery is performed under general anesthesia. After preparing the patient on the operating table, we sterilize the area of operation. If necessary, we place a compression cuff on the thigh, which allows blood stasis in the leg during surgery. Frequently, there are three skin incisions required for the implementation of arthroscopic reconstruction of anterior cruciate ligament - one on the anterior and posterior part of the knee (similar to a standard knee arthroscopy) and an additional few centimeters long skin incision in the area of tendon graft removal. When, in the reconstruction of ligaments, the tendon of semitendinosus and gracilis muscle is used, a cut on the inner side in the upper third of the lower leg is necessary. If the patellar ligament is used, the cut is made in the middle of the front part of the knee.
Due to the insertion of implants which are used to attach the tendon on the bone canal, are sometimes, besides the main ones described, also needed smaller skin incisions on the anterior and posterior part of the knee. Additional skin incisions may also be required because of additional, during the arthroscopy detected, accompanying joint impairments.
Surgery usually starts with a diagnostic knee arthroscopy, which is intended for a thorough examination of the knee and detection of accompanying injuries of other joint structures, such as medial and lateral meniscus, cartilage surface and posterior cruciate ligament. During the surgery, the knee joint is filled with sterile saline. It is a solution of NaCl, which rinses the joint, stretches it a little and in this way provides good visibility inside the joint. In case of detection of associated injuries, if possible, we appropriately treat them during arthroscopy. In meniscus tear, this may involve partial or total removal of the meniscus, in rare cases it can also be stiched. In major cartilage affection we can decide for boring the damaged area or performing microfracturing. With such procedure we achieve a partial renewal of the defective cartilage surface by fibrous cartilage. In larger cartilage defects, treatment may require additional surgical procedure, but in rare cases the surgeon can, because of advanced cartilage surface's wear, decide that reconstruction of cruciate ligament will not be performed.
After the removal of tendon graft, the preparation of bone tunnels in the area of the tibia and femur, through which the tendon graft will be laid in, follows. For a successful operation, the precise position of the bone tunnel, both in the region of the tibia and femur, is very important. In some cases, the surgeon decides to implement a double bundle reconstruction of anterior cruciate ligament. This kind of operation is possible mostly for those with larger and stronger knee tendons.
The advantage of this operation is to be closer to the reconstruction of the natural anatomy of the anterior cruciate ligament, which is composed of two bundles - anteromedial and posterolateral. In this way, we achieve a better rotational stability of the knee. But double bundle technique also has some disadvantages, for instance, a longer operation, demanding operative technique, difficult revision in case of re-tearing of cruciate ligaments, a bigger risk for interoperable complications such as fracture of bone tunnel wall.
In rare cases, during the diagnostic arthroscopy it is found out that a part of the anterior cruciate ligament is still preserved. In this case, the surgeon might decide to maintain this part and to strengthen the existing ligament. The course of this operation is very similar to the one of the anterior cruciate ligament reconstruction with double bundle technique. In this case only single bundle is reconstructed, the preserved part of its cruciate ligament, in this case represents the second bundle.
One of the key factors for success of anterior cruciate ligament reconstruction is a very accurate determination of the position of bone tunnels, through which the tendon graft will be led. In determining this position, the arthroscopic examination of the joint has a great advantage over the conventional open surgery. For precise drilling of bone tunnels, we also help ourselves with specific target instruments. The standard technique of anterior cruciate ligament reconstruction requires drilling of one bone tunnel through the tibia, usually 8-9mm in diameter and one bone tunnel, similar diameter through the femur. In double bundle technique it is necessary to make two thinner bone tunnels, in diameter 5-6mm, over the tibial and two tunnels more through the femoral.
When the tunnels are drilled, the implementation of the leading stitches follows, with which is trough a tunnel dragged the tendon graft. At the end of the operation, the tendon graft is attached first to the femur and then to the tibia. For the attachment of the tendon graft in the femoral area we can use interference screws of different materials, resorbable transversal pins or a special titanium button. On the tibia, the tendon is usually attached with an interference screw. Which method of attachment of tendon grafts is the best for your knee, your surgeon will explain during the surgery. In some cases during surgery ,due to changed circumstances, a different method of attachment of the tendon graft can be used.
Recovery after arthroscopic reconstruction of anterior cruicate ligament
Due to the minimal invasiveness, the recovery after arthroscopic reconstruction of anterior cruciate ligament is faster comparing to the conventional surgery. It is very important that the patient is aware and understands that the absence of knee swelling and pain and full mobility of the knee does not mean that the knee has fully healed and is capable of full loading. With arthroscopic surgery we achieve minor post-operative pain, knee swelling disappears quickly, and full range of motion returns faster comparing to the conventional open surgery, but we cannot speed up growing of the tendon graft in the bone or the process of tendon revascularization.
It takes a few months for this process to complete. It is a biological process of healing, which we normally stimulate with appropriate physical therapy and controlled loading, but we cannot significantly reduce it. Only a complete ingrowth of bone tendon graft and revascularization that has a vitally recovered cruciate ligament as an outcome enables that this type of reconstructed cruciate ligament is capable of withstanding burdens that occur at full knee loading in major activities. Usually this is achieved in 6 months after surgery. Early uncontrolled or excessive knee loading in the first few months after surgery may lead to extension of the tendon graft and the consequently to knee instability or even releasing the fixation of bone graft.
Rehabilitation after the anterior cruciate ligament reconstruction is difficult. It is crucial that it is controlled and under the supervision of a physiotherapist, who is suitably qualified and knows the limits and objectives of the various phases of recovery very well. It is strongly recommended that the physical therapy is individual and that the program adapts to the progress and capabilities of every individual. Immediately after the operation, it is necessary to cool the knee with ice several times a day, which reduces swelling and pain. Immediately after surgery, a full loading of the operated leg is allowed. First few days patients usually help themselves walking with crutches. Due to weakening of the leg muscles when walking with support, it is recommended to give up the support as soon as possible. On discharge, each patient receives instructions regarding post-operative checkups and early rehabilitation.
Reconstruction of anterior cruciate ligament using tendon allograft
When choosing a tendon graft in surgery of anterior cruciate ligament reconstruction, we can make a choice between a patella tendon (taking the middle third of patella tendon with belonging bone blocks), quadriceps muscle tendon (tendon withdrawal of the quadriceps muscles at the attaching spot on the kneecap) or tendon of semimembranosus and gracilis muscles (tendons of flexors on the back of the thigh that are taken through a small incision on the interior part of the knee). For all of these forms of reconstruction it is common that in operation of replacing the defective anterior cruciate ligament we use autologous tendon, therefore the patient's own tissue. Another option, which in recent years has become increasingly widespread, is the usage of a tendon graft that it is not the patient’s. This is the tissue that is acquired by the deceased and was previously processed under strict rules ensuring complete sterility, and consequently the safety of use. Using tendon allograft in anterior cruciate ligament surgery has several advantages. The most important one among these is undoubtedly the fact that it preserves all other tendons in the knee. Thus, the operation itself does not regulate the function of other muscles and tendons in the knee, which significantly facilitates post operative recovery. The great advantage of this type of tendon graft is also less invasiveness of the procedure, because in the operation is not required to extract patients' tendons. Consequently, the pain and swelling in the early postoperative period are significantly smaller and recovery is faster .When using tendon allograft, the quality of the reconstructed anterior cruciate ligament also does not depend on the strength and quality of his own tendon, which is sometimes a problem, especially in slim women who have relatively delicate tendons. The main disadvantage of using tendon allograft in surgery of anterior cruciate ligament reconstruction is a relatively high price of transplants. Currently only few specialized institutions in the USA carry out a proper process and treatment of these tissues. Due to special treatment conditions, this increases the cost of transplants.
In our institution, we have been performing operations using tendon allografts since 2009. Given the relatively high costs associated with such operations, we mostly recommended it for athletes who expect the most perfect function of the knee and due to anterior cruciate ligament reconstruction do not want to compromise other functions of other tendons and muscles, and of course they want a rapid recovery. Using tendon allograft, we can certainly come much closer to these high expectations.
Artros company is an accredited center for performing surgery in which tendon allografts are used. When carrying out such procedures with the use of foreign tissues, the procedures and standards that are prescribed by the Slovenia Transplant organization and Euro transplant are used.