You have torn your anterior cruciate ligament (ACL). Patients experience the lack of the ACL in very different ways. Not all patients are restricted by this and need stabilizing surgery. Some adapt their sporting activities and get along well without complaints in everyday life. However, in around one third of patients, there is already a feeling of instability in daily life activities (e.g. giving way). Due to this instability, injuries to the meniscus and cartilage can occur, which must be prevented. A stable knee joint is essential for certain sports (contact sports, stop-and-go sports). The strain on the knee joint in pivoting sports (such as soccer, handball or basketball) is so great that one must advise against participation un-less there is sufficient ACL.
Whether you need a stabilizing operation as part of an isolated ACL rupture depends on whether you experience instability and whether you need a stable knee at work or during sporting activities. The following three factors are decisive: the extent of the subjective instability, the desired level of activity and possible accompanying injuries (i.e. meniscus, cartilage).
The clinical examination of your knee joint shows a sliding forward of your injured lower leg (drawer test) in comparison to the other uninjured lower leg. However, the so-called pivot shift test is also crucial as the rotational stability of the knee joint can be assessed. As part of an acute injury, this test can be uncomfortable or even painful. A strong rotational instability in the clinical examination is an important indicator for the decision-making about the correct therapy. If rotation instability is present, the joint should be stabilized using ACL reconstruction.
Isolated injuries to the ACL can be treated primarily conservatively in patients without symptomatic instability and those who do not participate in sporting activities. Physiotherapeutic treatment can improve the muscular stabilization of the knee joint. If surgery is indicated due to the instability of the knee joint, due to the desired level of activity or due to accompanying injuries, the ACL will be reconstructed.
Various grafts are available for the reconstruction of the ACL. As a rule, the body’s own tendons are removed and used as an ACL replacement. Every graft and surgical technique has advantages and disadvantages. Accompanying injuries must also be taken into account when choosing the graft. We usually use the tendon of the semitendinosus muscle (hamstring) as the transplant of choice. In contrast to other techniques, the removal of this tendon is comparatively less disruptive or painful. This is also the reason why it is used most frequently for this operation worldwide. If the tendon is not sufficiently long or thick, the tendon of the gracilis muscle can also be removed.
The tendon can be folded twice and thus replace the ACL as a quadruply strong bundle of tendons.
The operation is performed arthroscopically via two small incisions at the front of the knee. An additional 5 cm incision is made on the inside of the shin head (tibia) to remove the tendon(s) and drill the tibial tunnel.