Anterior Cruciate Ligament Lesions
It is especially common in recreational, amateur and professional athletes who play basketball, football, American football and skiing. ACL injuries are more common in females than male athletes doing the same sport (2.4-9.7%).
Anatomy-Biomechanics: The ACL attaches to the posterior-inner edge of the proximal lateral femoral condyle and distally to the anterior-outer edge of the anterior tibial process. While the anterior-medial band is taut in flexion, the posterolateral band is loose, and vice versa in extension. The ACL is inside the capsule but outside the synovial sheath. Innervation is from the posterior branch of the tibial nerve. This neural network is believed to be responsible for sensing deformation and position changes in the ligament during movement (proprioception). The ACL is the most important ligament that restricts the anterior movement of the tibia (85%), and the tension in the ligament reaches its highest level in full flexion. Again, full extensiondatibial rotation helps prevent varus and valgus angulation. As a result of ACL injury, anterior and rotational instability occurs in the knee joint.
Etiology: High-risk sports for ACL injuries include football, baseball, soccer, basketball, and skiing. ACL injury occurs when touching the ground (usually a combination of hyperextension/pivot) after sudden change of direction, shearing or jumping in non-contact sports. In contact sports, ACL injuries are often accompanied by other ligament and meniscus injuries. Classically, ACL, medial lateral ligament, and medial meniscus injuries occur with valgus stress. If the femoral notch index (the ratio of the width of the femoral notch to the width of the femoral condyles) is below 0.2, there is notch stenosis. Notch stenosis carries a high risk for ACL injury in non-contact sports. ACL injuries are more common in women. It is evaluated that training method, strength-body weight ratio, joint laxity, muscular composition and shallowness index are effective in this. However, these factors need to be investigated in comprehensive studies. Although it has been shown that the menstrual cycle is not associated with ACL laxity, the debate continues. Again, unsuitable sports shoes and artificial turf fields are also predisposing factors.
Diagnosis: Athletes who have suffered an ACL injury report hearing a pop on their knee at that moment. The knee joint swells due to bleeding within a few hours after the injury. Athletes cannot continue sports due to pain, fluid and mobility in the knee. On examination, there is swelling, immobility, and pain in the knee joint. Again, if there is tenderness along the knee joint line, meniscus tear, and if there is tenderness at the attachment points of the inner and outer lateral ligaments, ligament injury should be considered. A meniscus tear may threshold 50% of ACL tears.
Tests used for diagnosis of ACL injuries may not be performed due to pain in acute trauma.