User:TylerBouchard/Anterior cruciate ligament injury

Epidemiology
There are around 200,000 ACL tears each year in the United States, with over 100,000 ACL reconstruction surgeries per year. Over 95% of ACL reconstructions are performed in the outpatient setting. The most common procedures performed during ACL reconstruction are partial meniscectomy and chondroplasty. Risk factors for ACL tears include female anatomical structures, specific sports, poor conditioning/fatigiue, and playing on a turf field. Age and sex adjusted incidence rates of ACL tears showed an incidence rate of 68.6 per 100,000. When breaking down between males and females adjusted for age, males had a higher incidence rate of 81.7 per 100,000 while females had an incidence rate of 59.2 per 100,000.

Anatomical Risk Factors

Individuals with a higher body mass index (BMI) and a narrower femoral condylar notch had an increase risk of tearing the ACL. One study showed that an increased Q-angle and excessive tibial torsion could lead to an increased risk of ACL injury. While anatomic risk factors are interesting and may contribute to an increased risk of injury there is no direct correlation between anatomic variables and acl injury. Most research suggests that faulty bio-mechanics and muscular deficiencies contribute more to injury risk.

Activity Based Risk Factors

When breaking down incident rates based on age between sexes, females between the ages of 14-18 had the highest occurrence of injury with 227.6 per 100,000. Males between the ages of 19-24 had the highest rates of injury with 241 per 100,000. Rates of re-rupture among collegiate athletes were highest in male football players with 15 per 10,000, followed by female gymnasts with 8 per 10,000 and female soccer players with 5.2 per 10,000. One of largest predictors of ACL injuries is dynamic valgus movement. Valgus torque at the knee leads to increase anterior tibial translation causing a greater load to be placed on the ACL.

High school athletes are at increased risk for ACL tears when compared to non-athletes. This risk increases with certain types of sports. Among high school girls in the US, the sport with the highest risk of ACL tear is soccer, followed by basketball and lacrosse. In the US women's basketball and soccer experience the most ACL tears then all other sports. The highest risk sport for high school boys in the US was basketball, followed by lacrosse and soccer. In the world of basketball, women are 5-8 times more likely to experience an ACL tear then their male counterpart. Children and young athletes may benefit from early surgical reconstruction after ACL injury. Young athletes who have early surgical reconstruction of their torn ACL are more likely to return to their previous level of athletic ability when compared to those who underwent delayed surgery or nonoperative treatment. They are also less likely to experience instability in their knee if they undergo early surgery.