The anterior cruciate ligament (ACL) is an important structure in the knee that provides stability with movement. It is particularly important for athletes who participate in dynamic sports involving lateral and cutting movements, pivoting, and quick changes in speed, such as lacrosse. There are two mechanisms of ACL injury: contact and noncontact. A contact injury occurs when a sudden force occurs on the outside of the knee, such as from contact with another player, causing the knee to bend inward. A noncontact injury can occur when a player plants their foot and quickly pivots causing a twisting force at the knee. Most players who injure the ACL hear a “pop” and experience instability and buckling and immediate swelling.
The injured knee should be immobilized and kept non-weight bearing if possible until evaluated by physician, while following the RICE protocol of rest, ice, compression and elevation. Once diagnosed with ACL tear through MRI, surgery is the treatment option 90% of the time, especially if an athlete is planning on returning to sport. Most athletes will attend physical therapy pre-operatively and then post-operatively. Rehab after ACL reconstruction involves regaining range of motion, strength, balance and flexibility and generally occurs for about 6-12 months with return to sport within a year pending physician clearance.