Female athletes are more likely to jump and land with their knees relatively straight and collapsing in towards each other, while most of their bodyweight falls on a single foot and their upper body tilts to one side. Several theories have been described to further explain these imbalances. These include the ligament dominance, quadriceps dominance, leg dominance, and trunk dominance theories.The ligament dominance theory suggests that when females athletes land after a jump, their muscles do not sufficiently absorb the impact of the ground. As a result, the ligaments of the knee must absorb the force, leading to a higher risk of injury. Quadriceps dominance refers to a tendency of female athletes to preferentially use the quadriceps muscles to stabilize the knee joint. Given that the quadriceps muscles work to pull the tibia forward, an overpowering contraction of the quadriceps can place strain on the ACL, increasing risk of injury.Leg dominance describes the observation that women tend to place more weight on one leg than another. Finally, trunk dominance suggests that males typically exhibit greater control of the trunk in performance situations as evidenced by greater activation of the internal oblique muscle. Female athletes are more likely to land with their upper body tilted to one side and more weight on one leg than the other, therefore placing greater rotational force on their knees. Hormonal and anatomic differences
Before puberty, there is no observed difference in frequency of ACL tears between the sexes.
Research has demonstrated that by training the muscles around the knee appropriately through exercise treatment, the body can learn to control the knee again, and despite extra movement inside the knee, the knee can feel strong and able to withstand force.Typically, this approach involves visiting a physical therapist or sports medicine professional soon after injury to oversee an intensive, structured program of exercises. Other treatments may be used initially such as hands-on therapies in order to reduce pain. The physiotherapist will act as a coach through rehabilitation, usually by setting goals for recovery and giving feedback on progress. Estimated non-surgical recovery timeframe is 3–6 months and depends on the extent of the original injury, pre-existing fitness and commitment to the rehabilitation and sporting goals. Some may not be satisfied with the outcome of non-surgical management and may opt for surgery later. Surgery
ACL reconstruction surgery involves replacing the torn ACL with a "graft," which is a tendon taken from another source. Grafts can be taken from the patellar tendon, hamstring tendon, quadriceps tendon from either the person undergoing the procedure ("autograft") or a cadaver ("allograft"). The graft serves as scaffolding upon which new ligament tissue will grow.The surgery is done with an arthroscope or tiny camera inserted inside the knee, with additional small incisions made around the knee to insert surgical instruments.