Knee

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.

Ligaments are rope like bands of tough, leathery tissue that stabilize our joints. They span across the joint like a bridge, anchored to one bone above the joint, and another bone below the joint. Their purpose is to allow the joint to move freely through its normal range of motion, but to resist motion in abnormal directions. There are four major ligaments in the knee: two collateral ligaments (medial and lateral) on the sides of the joint and two cruciate ligaments (anterior and posterior) in the center of the joint. These ligaments are thick, about the same diameter as your pinky finger, and they are very strong, but if you twist your knee hard enough, you can tear one or more of them.

The ligament can be completely torn or just partially torn, depending on the injury. After tearing a ligament, you are likely to experience pain, stiffness, swelling and weakness in your knee. These symptoms are likely to subside with time, but you may notice a sense of instability or “wobbliness” once you feel good enough to start walking around again. Tears of the medial collateral (MCL) and lateral collateral (LCL) ligaments usually heal without surgery. Your doctor may recommend a brace to stabilize your knee while the ligament heals, and you may have to avoid certain activities until the ligament is healed and your knee muscle strength has returned. Tears of the anterior cruciate (ACL) and posterior cruciate (PCL) ligaments don’t heal well on their own. If you are an active person who enjoys sports or has a physically demanding job, an ACL tear will likely require surgical reconstruction using either a cadaver (organ donor) graft or a graft from another part of your own knee (hamstrings and patellar tendon tissues are often used). These grafts are used to replace the torn ligament since sewing the “stumps” of the torn ligament back together does not work. The graft is attached to the patient’s bone using a variety of fixation devices, such as screws or pin, depending on your surgeon’s preference. While ACL reconstruction is generally considered major surgery, the operation has an excellent track record for getting college, recreational and professional athletes back to the sports and activities they enjoy. Most patients are on crutches for one to two weeks, and are in physical therapy for one to two months. ACL reconstruction patients typically don’t return to high demand sports until six to nine months after surgery. The treatment of PCL tears is more complicated, and specific recommendations vary depending on the details of the injury and the individual patient.

The patella is the formal name for the knee cap. This bone lies on the front of the knee joint and is encased in the quadriceps muscle. It serves as a fulcrum and improves the efficiency and power of the quadriceps muscle to extend the knee. With knee flexion and extension, the patella is compressed against the groove on the top of the knee. It is designed to track straight up and down and is covered on its undersurface with cartilage that serves as a cushion. It is estimated that patellar cartilage can feel 4-5 times body weight with walking and up to 8 times body weight with stairs and squatting.

Pain in the Patellofemoral joint is typically seen in women more frequently than men and results from poor tracking of the patella relative to the groove on the top of the knee. This improper tracking can overload the cartilage and create pain in the front of the knee. It typically will get worse with an increase in training or exercise and then can become painful with normal activity such as squatting and stairs.

Treatment for this condition usually involves anti-inflammatory medications and occasional knee injections to help control flares. Chronic management focuses on physical therapy to strengthen the vastus medialis muscle to help improve tracking of the joint, activity modification, bracing, and controlling body weight. Rarely surgery may be indicated.

The patella occasionally can dislocate or pop out the knee joint to the outside. This is occurs more frequently in women than men and usually involves a distinct injury where the knee cap slides outside of the normal groove on the top of the knee. In most situations the patella will pop back into place on its own and only occasionally will the knee have to be extended to manipulate it back in place. The knee can be quite swollen after dislocations.

Treatment for this depends on how often this has happened. In first time dislocations, the knee is treated usually with bracing and physical therapy. Occasionally, an MRI may be ordered if there is concern that there was an associated injury to the cartilage on the undersurface of the patella. For those who have dislocated multiple times and the knee can not be trusted, surgery is often recommended to either repair the soft tissue restraints around the patella and or to correct the alignment of the joint.

The knee joints is the meeting place of 2 large bones - the femur and tibia. The bones are lined by articular cartilage - this is what wears out in arthritis. Sitting between the two bones are shock absorbers called the meniscus. There are two meniscus - medial and lateral - this describes their location in the knee.

The meniscus performs many functions in the knee but the most important function is to absorb the shock that the knee experience during activity.

The meniscus can tear by an acute injury or tear wearing out over time. The meniscus does not heal once torn. The diagnosis is made by history, physical exam, and MRI.

Some meniscus tears are relatively asymptomatic and therefore treated without surgery. Meniscal tears that are symptomatic are treated surgically. At surgery the torn part of the meniscus is repaired or removed.

This is a significant injury to the ligament that attaches the kneecap to the lower leg. Tears typically occur in jumping and running athletes during an explosive maneuver. These injuries always require surgical intervention. The surgery is to reattach the tendon back to the patella bone. Rehabilitation from this surgery can take approximately 4-6 months.

This is a significant injury to the ligament that attaches the kneecap to the lower leg. Tears typically occur in jumping and running athletes during an explosive maneuver. These injuries always require surgical intervention. The surgery is to reattach the tendon back to the patella bone. Rehabilitation from this surgery can take approximately 4-6 months.

Tendonitis is a medical word used to describe inflammation of a tendon. A tendon attaches muscle to bone. Repetitive use of a muscle tendon unit and/or age or trauma can cause tendonitis. Early tendonitis can be treated with rest, ice, and anti-inflammatory medication. Refractory cases may require a cortisone injection and/or surgical intervention. Tendonitis is more common in aging athletes secondary to decreased vascularization. Sever cases of tendonitis can cause partial tearing as well as complete tearing requiring surgery.

Osteoarthritis or degenerative arthritis of the knee is an increasingly common problem involving both men and women. This condition is common in individuals over the age of fifty, individuals who are overweight and in those who have had previous injury to or surgery of the knee.

Arthritis of the knee can be confidently predicted when the individual presents with knee pain, limited duration morning stiffness, reduced function, restricted motion of the knee and bony enlargement or increased size of the knee.

Treatment of the arthritic knee includes activity moderation/modification, weight loss if appropriate, exercise (bicycle or water exercise), avoidance of pain provocative activity, heat or ice, and oral non-prescription medications such as acetaminophen, ibuprophen and naproxen sodium.

Injection of corticosteroids or viscosupplementation (lubricants) may be used. Arthroscopic debridement or removal of loose bone and/or cartilage may be useful in selected individuals.

When the above methods fail, and the individual is intolerant of pain and incapacitation, knee joint replacement may be required to control pain and allow comfortable mobility.