An anterior cruciate ligament (ACL) tear is an injury to the knee commonly affecting soccer players, basketball players, skiers, gymnasts, and other athletes. About 70% of ACL tears are the result of non-contact injuries; 30% are the result of direct contact (player-to-player, player-to-object). Women are 4-6 times more likely than men to experience an ACL tear.

Usually, you will be examined by a physical therapist or an orthopedic surgeon immediately following injury. Most people who sustain an ACL tear will undergo surgery to repair the tear; however, some people may avoid surgery by modifying their physical activity so that they don't put a lot of stress on the knee. A select group can actually return to vigorous physical activity following rehabilitation without having surgery.

Your physical therapist, together with your surgeon, can help you determine if non-operative treatment (rehabilitation without surgery) is a reasonable option for you. If you elect to have surgery, your physical therapist will help you both prepare for surgery and recover your strength and movement following surgery.
 

 When you tear the ACL, you may feel a sharp, intense pain or hear a loud "pop" or snap. You might not be able to walk on the injured leg because you can’t support your weight through your knee joint. Usually, the knee will swell immediately (within minutes to a few hours), and you might feel that your knee "gives way" when you walk or put weight on it.

If you see your physical therapist first, your therapist will conduct a thorough evaluation that includes reviewing your health history.

Your therapist will ask you whether you: 

Felt pain or heard a pop when you jumped, stopped quickly when running, turned your leg with your foot on the ground, or stretched your knee farther than usual

Had a direct hit to the leg while your foot was planted on the ground

Saw severe swelling around the knee in the first 2-3 hours following the injury

Felt your knee buckling or giving way when you tried to get up from a chair, walk up and down stairs, or turn while walking

Your physical therapist also will perform special tests to help determine the likelihood that you have an ACL tear. For instance, the therapist may bend your knee and gently pull on the lower leg (called the "anterior drawer" test or the "Lachman" test). The therapist also might use the "pivot shift" test, gently bending and twisting your knee at the same time. (You might feel some discomfort or instability during these tests, which is normal.) Your therapist may use additional tests to assess possible damage to other parts of your knee.

The orthopedic surgeon may order further tests, including magnetic resonance imaging (MRI), to confirm the diagnosis and also to rule out other possible damage to the knee.

Once an ACL tear has been diagnosed, you will work with your surgeon and physical therapist to decide if you should have surgery or if you can try to manage your recovery without surgery. If you don’t have surgery, your therapist will work with you to restore your muscle strength, endurance, and coordination so that you can return to your regular activities. In some cases, the therapist may help you to learn to modify your physical activity so that you put less stress on your knee. If you decide to have surgery, your therapist can help you both before and after the procedure.