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Anterior Cruciate Ligament (ACL) Tears

    Anterior Cruciate Ligament (ACL) Tears

    Anterior Cruciate Ligament Rupture or Anterior Cruciate Ligament Tear

    Definition of the Disease: 
    The anterior cruciate ligament is one of four main stabilizing ligaments in the knee.  There is the medial collateral ligament, the anterior cruciate ligament, the posterior cruciate ligament, and the lateral collateral ligament.  Of the four, the anterior cruciate ligament seems to be the most important in allowing patients to return back to sports requiring cutting and pivoting movements.  The symptoms of an anterior cruciate ligament tear basically are a feeling of instability of the knee.  The patient lacks confidence in the knee.  The patient lacks the ability to stop quickly and change positions because the knee gives out and, once this happens, he/she has pain for a period of time and the knee then will usually swell up and hurt for a period of time until it recovers from this giving way episode.  Keep in mind, however, that the patients who do not normally engage in ACL-dependent activities, such as walking straight ahead, running or jogging, swimming, and bicycling, can function quite well without an anterior cruciate ligament, so not everyone who tears their ligament necessarily has to have it fixed; I think they have to decide if they can live with the occasional instability that occurs even with daily living when they stop and change positions quickly.

    How can this Condition be Treated?
    This condition can be treated most definitively with anterior cruciate ligament reconstruction.  Anterior cruciate ligament reconstruction generally is accomplished by placing a new anterior cruciate ligament where the old one was that has been created from a ligament or a tendon taken from another part of the patient’s knee; usually the hamstring tendons can be used or portion of the patellar ligament, which is just below the kneecap in a normal knee.  Once this tissue has been fashioned into a form that can become a new ACL, it is then inserted via an arthroscopic technique.  The surgery generally takes about an hour-and-a-half to two hours and can be done as an outpatient, meaning the patient can go home after the surgery.  The rehabilitation process after ACL reconstruction is fairly rigorous.  Patients require about four to six weeks of physical therapy in order to maintain their range of motion, start the strengthening process, and get their gait back to normal.  One of the drawbacks of ACL reconstruction surgery is that patients are not permitted to engaged in ACL-dependent sports, such as skiing, tennis, racquetball, hockey, basketball, volleyball, football, Ultimate Frisbee, etc., for nine months following the operation because the ligament, which has been replaced, takes that long to mature and strengthen to its final functional status.  However, during that nine months patients can run, they can lift weights, they can bicycle, they can do hiking and swimming.

    If left untreated, ACL-deficient knees can progress on to arthritis, although not all ACL-deficient knees will progress to arthritis.  Some will progress with time because of the abnormal sliding and slipping of the knee; other knees seem to be a little better compensated and we do not see the progress of arthritis.  Usually the arthritis in an ACL-deficient knee does not show up for ten to 15 yeas after the ligament is torn and left untreated. 

    Can Braces and Physical Therapy Substitute Sufficiently for an ACL-Deficient Knee?
    Generally, physical therapy is not effective in stabilizing a knee that has undergone an ACL tear.  Strengthening of the muscles, quadriceps, hamstring, and calf muscles, around the knee certainly can help to some degree with the patient’s agility, but it does not substitute for the stabilizing effect of the anterior cruciate ligament.

    Braces can be somewhat beneficial, although they are not quite tight enough to really completely diminish the instability that one feels when their ACL is gone.