If your ACL is injured, it is important that you strengthen all of the muscles around your knee joint and avoid certain positions. A physical therapist can help teach you how to avoid tearing your ACL completely. There will also be a lot of pain with this injury and a physical therapist can help to treat this pain when you are at the clinic and at home. If your ACL is completely torn, depending on your age, you may need surgery to repair it. Whether or not you need surgery, you will need to rehabilitate your knee so that you do not feel limited in your daily functions. A physical therapist can help you to strengthen your knee joint and decrease your chances of injuring other structures around your knee. They can also help you to return to your activities that you were performing before you injured your ACL.