Some people think that some girls are more prone to damaging the ACL than others. Prevention can help reduce injury to the ACL, but is not guaranteed. A good strength program along with proper warm up and stretching will help decrease the number of injuries, not only to the ACL but to other body parts as well. The muscles that help take the stress off of the knee joint are the quads, hamstring, hip abductors, hip adductors, hip extensors, hip flexors, and recently found out that the glutes also help. Also, especially in basketball, athletes have to be taught to land "soft". By this I mean to not land with your legs fully extended (straight). This helps reduce the number of hyperextension injuries in the knee, which is one mechanism that injures the ACL. Foot orthotics have been shown in the past to help reduce leg injuries such as shin splints, knee and ankle injuries, back injuries, and hip injuries. Think of the body as a stack of blocks. If all the blocks are straight then the stack is stable, if one block is off then the whole stack is unstable. Since the base of the body starts at the feet then you should protect your feet by taking good care of them. Identify if you have flat feet or high arches. If you do then a good orthotic would be a good decision. Now, just because you do all of this does not mean you will NEVER have a knee injury. Some people have asked me if there is a brace that will eliminate ACL injuries. The answer is NO. There is not a brace that will COMPLETELY eliminate ACL injuries, but there are braces to help reduce ACL injuries.