A torn Anterior Cruciate Ligament (ACL) is one of the most serious knee injuries that mainly affect athletes involved with dynamic or cutting activities such as soccer, football, basketball and etc.  The ACL is a ligament that runs diagonally by starting on tibia and inserting on the femur and it prevents the tibia from sliding in front of the femur and it provides some rotational support to the knee as well.

The mechanism for these injuries is usually a sudden slow down (deceleration) couple with a cutting or pivoting movement, or someone who lands or has someone landing awkwardly on their knee. It is one of the most commonly injured ligaments in the knee and one of the main reasons for knee surgery in younger adults and children. In the United States the incidence of ACL injuries is estimated at around 200,000 each year, and at least 100,000 of these injuries have surgical interventions to repair the torn ACL and other tissues, as 50% of ACL injuries involve other structures or tissues of the knee. The incidences of ACL injuries are higher in high-risk or contact sports, such as football, hockey, basketball, skiing, and soccer,

The rates of the cause of ACL tears were found to be 30% for direct contact with another player or object and the rest through non-contact causes. Another important issue plaguing ACL injuries is that women are more likely to have an ACL injury in many sports, with women having sometimes three times the risk of an ACL injury compared to men of the same age group and sport. This is a hotly debated topic and the International Olympic Committee (IOC) has even released a position and research paper about the topic. There are many reasons behind this discrepancy, as there are many hypotheses but nothing has proven yet, ranging from differences in physical conditioning, muscular strength, neuromuscular control, pelvis and lower-extremity alignment, and the effect that estrogen has on ligaments.

The way people know they have an ACL injury is that people suddenly feel their knee becoming unstable or painful when putting weight on it. In complete tears a “popping” sound may be heard, and some severe swelling in the knee is accompanied within 6 hours of the initial injury. Other symptoms include a loss of full knee range of motion, pain or tenderness along the knee joint line, and discomfort while walking. If you’ve experienced any of these kinds of symptoms while participating in a sports or any other activity, stop the activity right away and consult with your medial professional, such as your doctor or physiotherapist.  In the follow-up article we will talk about what are the treatment options, and the prognosis for ACL tears and injuries.