Meniscal Tears

Running Head: Treatment, Diagnosis and Types







Treatment, Diagnosis and Types of Meniscus Tears

Jiovanni Nunez

Christopher Columbus High School































Abstract

One of the most important parts of the knee is the meniscus. With two menisci in each knee, they help us stand and walk while also preventing osteoarthritis. When overworked however, the menisci can tear or become worn down. They can tear in a number of ways and each type of tear affects the knee in different ways. Treatment for meniscal tears can range from very complex to rather simple procedures, depending on the severity of the tear. The meniscus can either be sewn back together, or part of it can be removed through surgery. A meniscal tear can also be treated through various forms of conservative treatment. If left untreated however, the tear could worsen, or other injuries could develop as a result.

   



























The menisci (singular: meniscus) are crescent shaped discs of tough and rubbery fibrocartilage located in the knee in between the femur (thigh bone) and the tibia (shin bone). Although the four largest menisci are found in the knees, other menisci can also be found in other joints, such as the wrist and ankle. The main functions of the tibiofemoral menisci are to distribute the weight of the body over a larger portion of the tibial plateau, to act as a shock-absorber for the knee, and to reduce the friction caused by movement. Without the menisci, the entire weight of the body would be placed on one small point in each knee. This would cause abnormal excessive force in the joint and accelerate damage to the knee. In each knee, there are two menisci: the medial meniscus on the inside and the lateral meniscus on the outside. In between the menisci are the posterior and anterior cruciate ligaments, which provide the knee with stability. On the outer sides of the knee are the collateral ligaments. The menisci only receive a small supply of blood on the outer edge (characterized by a dark red tint) and no blood supply to the inner two-thirds. Meniscal tears generally occur on the inner edge, though even small tears on the innermost periphery can worsen and develop into large tears that can reach the outer edge. They are among the most common knee injury for professional and amateur athletes due to the increased amount of work that they place on their joints in order to compete.

Meniscal tears can usually be described by the location of the tear on the meniscus. These locations are identified as “zones.” There are four zones ranging from Zone Zero to Zone Three. Zone Zero is an injury to the farthest outer edge of the meniscus, or the synovial-perimeniscal vascular plexus. Zone One is an injury to the red vascular area in the outer one-third of the meniscus. Zone Two is an injury to the area around the border between the vascular (red) and avascular (white) areas. The fourth and final zone is Zone Three. Zone Three is an injury to the innermost one-third.

There are two general categories for meniscal tears: traumatic and degenerative. These categories differentiate the tear based upon the way that they form. Traumatic meniscal tears usually form when the knee is either bent or twisted violently and are most common in athletic individuals from age ten to forty-five. They commonly occur during violent sports, such as football, or other aggressive, full contact sports and high impact activity. Traumatic tears can occasionally occur in conjunction with injuries to the anterior cruciate ligament and the medial collateral ligament. When all three injuries are present together in a single knee, it is referred to as the “unhappy triad.” Complaints of catching and locking of the joint are most common in traumatic tears as a large piece of the damaged meniscus may have suddenly caught on the joint and prevented normal movement. Degenerative tears are more common in smokers and individuals from age forty and up. Degenerative tears slowly develop over years and they are thought to be caused by the natural aging process. They usually occur within the meniscus and divide it horizontally, although they can also form on the outside of the meniscus due to osteoarthritis in the knee. Degenerative tears hardly ever catch on the joint and usually only cause pain.

Within these two main categories, there are around eight different subcategories of meniscal tears and each type requires a slightly different procedure to treat them effectively. One of the simplest meniscal tears is a frayed-edge tear. In a frayed-edge tear, ragged fronds appear on the inner edge of the meniscus. This type of tear may either cause, or be caused by, osteoarthritis in the knee. Frayed meniscal edges are frequent and usually have little or no symptomatic consequences. The majority of meniscal tears will require a form of minimally invasive operative treatment known as an arthroscopic procedure. This form of surgery is performed to quickly treat and repair the tear and prevent it from worsening. Either a shaver or a biter is inserted into the knee to clean up the fraying meniscus edge and prevent the release of enzymes from the area. Surgery will prevent the tear from causing osteoarthritis or developing into degenerative fraying and restore full mobility to the knee of the patient. After surgery, there is a short recovery period as these are performed as outpatient procedures. Physical therapy will also be required to assist with the natural healing process and restore full mobility and strength to the area. Although most other surgery is necessary, there are instances where physical therapy alone can significantly improve the condition of the tear. If a patient prefers conservative treatment over the operative alternative, a more prolonged and intense physical therapy regime is required than if after the operative treatment had been performed. Icing might extinguish the patient’s pain for a few hours and an injection of methylpredinsoline acetate and lidocaine HCL will extinguish the pain for months. If a frayed-edge meniscus tear is left untreated, the tear could travel further up the meniscus and develop into degenerative fraying.

Degenerative fraying is the more severe form of a frayed-edge tear. In degenerative fraying, the entire meniscus (or most of the meniscus) becomes a mass of cartilage fronds. The severe fraying occurs both internally and externally and the meniscus eventually collapses on itself. This severely impairs the meniscus’ function to distribute weight and act as a shock- absorber for the knee. The rough edges formed by the fronds stress the smooth cartilage of the tibia and femur and causes osteoarthritis. In order to heal a case of degenerative fraying, complete meniscal reconstruction is required. Therefore, it is impossible to treat degenerative fraying without surgery. With an injury at this point of severity, the patient will experience a much longer and much more difficult recovery.

Today, diagnosing the severity of a meniscal tear is much easier for the physician as a result of the invention of magnetic resonance imaging (MRI.) A grading system based on the intensity and distribution on the magnetic signal reflecting off the meniscus in the MRI was developed to grade the intensity of meniscal degeneration. A more intense and widely distributed magnetic signal indicates serious degeneration. In the system there are three grades of degeneration: Grade One, Grade Two and Grade Three. Grade One is a focal or diffuse region of signal intensity within the meniscus. This indicates early meniscal degeneration and a chondrocyle-deficient region. Grade One degeneration can be found in healthy patients and is not usually clinically significant. Grade Two is a straight, horizontal line of increased signal intensity within the meniscal body. Grade Two degeneration usually develops out of Grade One degeneration and usually occurs in the posterior horn of the medial meniscus. Grade Two degeneration may or may not develop into Grade Three, although Grade Three degeneration usually occurs near regions of Grade Two.  Grade Three degeneration is a region of abnormal signal intensity that extends to at least one articular, or joint, surface. It is not uncommon for multiple regions of Grade Three degeneration to be located on a single meniscus. 

Another type of meniscal tear is the radial tear. Radial tears are one of the simplest tears and are characterized by a single, small, sharp split from the medial or inner rim, towards the lateral or outer rim. Because of how they move across the meniscus, radial tears are also known as transverse tears. Radial tears are one of the most common types of meniscal tears. In these cases, icing and methylpredinsoline acetate injections can suppress the patient’s pain to help him through physical therapy after surgery and can be used as a conservative treatment for small radial tears. During operative treatment to repair these tears, the surgeon may either trim away the tear or suture the tear. After either procedure, the patient will have to take a few weeks of physical therapy to accelerate healing and restore strength to the leg. Neglected radial tears may attempt to heal themselves, but instead they most often round off and move sideways across the meniscus, becoming parrot-beak tears.

Parrot-beak tears, also known as oblique tears, are the most common type of meniscal tear. They occur when radial tears, generally broad tears that receive no treatment try to heal themselves, but instead round themselves off and form a beak like frond. The larger frond has less support from the rest of the meniscus and may move around the joint capsule and catch on the joint, severely limiting the mobility and stability of the knee. During arthroscopic surgery to repair the tear, the frond is trimmed off. However, a meniscal reconstruction may be required to treat the exceptionally larger tears.

Another type of meniscal tears is the circumferential tear. A circumferential tear is a single tear that extends along a large portion of the length of the meniscus. Circumferential tears are also called longitudinal tears. The tears are parallel to the outer edge of the meniscus and are perpendicular to the tibial plateau. Circumferential tears commonly occur in physically active youths and young adults. They can also form in patients who have acutely torn their anterior cruciate ligament. . This type of tear usually begins in the posterior horn of the lateral meniscus, central to the popliteus tendon, and moves toward the anterior horn. Circumferential tears will always occur in the outer two-thirds of the meniscus and divide the meniscus into inner and outer sections. Shorter tears, or circumferential tears that do not span the entire length of the meniscus, are only visible in sagittal MRI views, although longer tears can be seen in both sagittal and coronal images. Once a circumferential tear has been diagnosed, the surgeon will probably have to perform a meniscal repair. The surgeon will suture the entire length of the tear to prevent the tear from worsening while it heals. As mentioned above, circumferential tears will always occur in the outer two-thirds; therefore the tear will receive an adequate amount of blood to heal itself. The patient will have to avoid putting too much stress on the knee to prevent the sutures from untying themselves and reopening the tear. Physical therapy will help the patient regain strength and accelerate healing. If the patient would prefer a more conservative treatment, immobilization of the joint will prevent the tear from worsening and allow the meniscus to properly heal. Icing, simple injections and specific injections will reduce the patient’s pain and increase the efficiency of the physical therapy. Untreated circumferential tears may move downwards, eventually ripping through the entire depth of the meniscal body. When this occurs, the circumferential tear becomes a bucket-handle tear.

Bucket-handle tears form when a circumferential tear moves through the entire depth of the meniscal body and the inner portion flips over, becoming caught on the femur’s rounded condyle. Because the anterior and posterior cruciate ligaments are in the center of the joint, the displaced portion rubs against them and could irritate them. Consequently, bucket-handle tears can very often be associated with cruciate ligament injuries. Bucket-handle tears generally occur on the medial meniscus, but they can also affect the lateral meniscus if the displaced section is long enough to travel over the meniscus and rub against the cruciate ligaments. These tears commonly occur in young adults with a history of locking, extension-block, or joint slipping due to displacement of central fragment toward the intercondylar arch. This type of tear locks the joint and prevents complete extension of the leg. If patients with a bucket-handle tear attempt to extend the injured leg, it will cause pain, worsen the tear, and cause the lateral meniscus to become injured as well as the medial. In these cases the surgeon will choose between various procedures to repair the meniscus, determining which is most appropriate depending on the location of the tear. If the tear is confined to the inner white area, the surgeon will simply trim off the displaced end because an injury to the avascular portion of the meniscus will have no chance of healing as this zone receives absolutely no blood flow. If the tear occurs in between the red and white areas, the surgeon will relocate the displaced end and suture it back to the meniscus. The blood will carry blood plasma and stem cell that will greatly assist in the healing. For tears confined to the outer red area, the surgeon will suture both ends back together and try to preserve the area because, with the most blood supply, the outer area has the best chance of completely healing. Bucket-handle tears may take a few months to heal, as the meniscus is almost completely split in two.

One of the most unusual tears is the horizontal-cleavage tear, or a fish mouth tear. A horizontal-cleavage tear is a horizontal split within the meniscus. The tear is usually hidden from view, though it can be evident in MRIs. The tear may appear to be located deep in the meniscus on the MRI, but in reality, they are usually only a few millimeters under any abnormal signals on the surface. Horizontal-cleavage tears will usually occur after minor injuries to the knee. Once the tear begins, it sets off a degenerative process horizontally throughout the meniscus, dividing it into a top and a bottom portion during its later stages. When the tear completely rips through the meniscus, the empty space between both portions now allows joint fluid to the meniscosynovial border where it can become trapped and form a meniscal cyst. Horizontal-cleavage tears can also occur in older patients with osteoarthritis. This type of tear can be difficult for an inexperienced surgeon. On the outer edge, the tear appears to be small, but as the surgeon trims away the cartilage, he discovers that there is deeper and more serious damage that seems to continue throughout the area. An experienced surgeon however, will understand the potential extent of these types of tears and trim away the avascular cartilage and suture the red outer area.

Another type of horizontal tear, though not as unusual or as serious as the horizontal-cleavage tear, is the flap tear. Flap tears occur on the surface of the meniscus, rather than in the center, as with the horizontal-cleavage tear. The flap formed by the tear can occasionally flip over and catch on the joint, causing pain and other symptoms usually associated with meniscal tears, such as joint stiffness and the inability to lock the knee. The flap usually flips outward, known as superior displacement, although inferior displacement, or flipping inwards, has also been known to occur. During surgery, the surgeon will simply trim away the flap. Usually, there will be enough meniscal body mass left to heal the damaged area and still provide the knee with adequate shock absorption. The surgical procedure for this type of tear requires a short recovery period for the patient, as well as just a few weeks of physical therapy, unlike with other meniscal tears.

Flap tears are only one type of tear in a small category of tears known as displaced meniscal tears. A tear enters this category when a fragment that is still partially attached to the meniscus, migrates to any other location within the joint. Any type of meniscal tear has the potential to become displaced and displaced meniscal tears occur in nine to twenty-four percent of all meniscal tear patients. Bucket-handle tears are the most common type of displaced meniscal tears as they can result from various other types of meniscal tears. Horizontal-cleavage tears can also become displaced when either the top or bottom portion slides inward, towards the center of the joint. Parrot-beak tears may become displaced when its frond catches on the joint. This could cause locking or catching and catching of the joint an eventually rip the frond free from the rest of the meniscus and  turn it into a free floating fragment. Either free floating fragments or unusually small menisci appearing on MRIs will usually warrant a search for a displaced meniscal tear by the surgeon.

Discoid Meniscus is a rare mutation occurring in the human meniscus. The mutation will usually occur in the lateral meniscus and produces a thickened meniscal body, shaping the meniscus like a disc that can usually be seen on two or more consecutive MRI slides. This sort of mutation usually goes unnoticed by the patient, although some people complain of pain, swelling, and snapping sounds occurring from the joint. Discoid Meniscus is generally more susceptible to meniscal tears than a normal meniscus. In Discoid Meniscus, the crescent of the meniscus is thickened and becomes shaped like a disc. Due to the increased thickness, blood supply and capsular attachment (the attachment of the meniscus to the capsule around the knee,) are diminished, which make the meniscus more prone to damage. The field of Orthopedics classifies the shape of Discoid Meniscus into three categories: incomplete, complete, and Wrisberg-Ligament variation. Discoid Meniscus is determined to be complete or incomplete based on the amount of coverage over the tibial plateau. The Wrisberg-Ligament variation of Discoid Meniscus does not affect the thickness of the meniscus, but instead causes the posterior horn of the meniscus to abnormally attach to the posterior cruciate ligament.

To diagnose Discoid Meniscus in a patient, coronal and transverse MRI images are used. On transverse images, Discoid Meniscus is diagnosed if the horizontal measurement between the free margin and the periphery of the meniscal body exceeds 1.4 centimeters. X-ray can also , though rarely, diagnose Discoid Meniscus if it shows increased joint spacing, squaring of the lateral femoral condyle, cupping of the tibial plateau, and hypoplasia of the lateral tibial spine. If a meniscal tear is diagnosed along with Discoid Meniscus and the patient complains of neither locking nor pain, simple exercises to stretch and strengthen the hamstrings and quadriceps can conservatively correct the tear. However, if the patient complains of severe locking and pain, and Discoid Meniscus is present; the tear will have to be surgically excised (removed). If the meniscus is severely damaged, it would have to be excised completely, however if it is still generally intact, a partial excision will adequately preserve the shock-absorber function of the meniscus and the patient should experience a full recovery from this treatment solution. 

Diagnosis and treatment of any meniscal tear is extremely important. If left untreated, the patient may experience other injuries to this area, mainly due to the existing weakness and fragility. Meniscal cysts are common injuries in patients with an untreated meniscal tear. In a meniscal cyst, joint fluid collects in a pouch on the meniscus. They mostly occur on the lateral meniscus along with horizontal-cleavage tears.  A quick way to treat a cyst is to drain it with a needle. This can usually be performed in the doctor’s office and doesn’t require any anesthesia, although the cyst may return if the tear that caused it has not yet been treated. The best treatment for a meniscal cyst is to arthroscopically treat the meniscal tear first and then drain the cyst. Meniscal cysts are not to be confused with popliteal, or Baker’s cysts, which occur in the back of the knee. The two cysts are similar in the way that they form, but Baker’s cysts are different because they are not affected by the meniscus.

The orthopedic surgeon will have a variety of methods to diagnose the presence, type, and intensity of a meniscal tear in a patient including, but not limited to, magnetic resonance imaging, differential diagnosis, range-of motion tests and, most common of all; routine physical examinations.

During a routine physical examination, the physician will perform various tests and check for the general symptoms of meniscal tears.  The general symptoms of a meniscal tear are the knee giving way, clicking, locking, limping and pseudo-limping which may be caused by muscle spasms. Locking of the knee can occur immediately after a displaced meniscal fragment sets in between the tibia and the femur. Other symptoms for a tear are pain within the knee, swelling of the knee, inability for the patient to bear any weight on the injured knee, and a loss of the range of motion. The physician will then perform the various range-of-motion and meniscal evaluation tests. The Appley Test is a simple meniscal evaluation test that has the patient prone(laying down) with the knee poised at a ninety degree angle. The foot is rotated internally and externally with distraction at first and then with compression. The presence of a meniscal tear will cause pain with compression. Today, this diagnosis method is rarely used as it has been discovered to be inaccurate. The second meniscal evaluation test is the McMurray Test. The McMurray Test is more accurate than the Appley Test, plus it can determine on which meniscus the tear is located. The patient is placed supine with the hip and knee in a flexed position. To test the medial meniscus, the leg is extended and the foot is rotated externally. To test the lateral meniscus, the leg is extended and the foot is rotated internally. A click heard or felt during either of these movements indicates the presence of a meniscal tear. The third and fourth tests are the Steinmann Sign Tests. In the Steinmann I Sign Test the patient’s knee is almost at extension and the leg is slowly rotated exteriorly and posteriorly, exteriorly for the medial meniscus and posteriorly for the lateral meniscus. The Steinmann II Sign Test has the patient’s knee slowly flexed. If tenderness occurs during flexion, the injury is probably a collateral ligament lesion. 

There are three range-of motion tests that the physician can use to determine the presence of a meniscal tear. The first test is the Bohler Test. With the knee at twenty to thirty degrees, valgus and varus pressures are applied to test medial and lateral collateral ligaments, respectively. Pain indicates an injury. The second test is the Apley Grinding Test. With the patient prone and the hip extended, the knee is flexed to at least ninety degrees. Downward pressure is exerted on the foot and the knee joint is rotated and compressed. Pain indicates the presence of a tear. The third test is the Payr Test. The knee is flexed to ninety degrees and varus pressure is applied to compress the posterior horn of the medial meniscus. Pain indicates a tear.

Two other tests that may be performed are the Ege’s Test and the Joint Line Tenderness test.  The Ege’s Test is a very specific test for meniscal tears. The patient squats with his feet pointed outwards, and then inwards. An audible clicking indicates a tear. Joint Line Tenderness however, is a very non-specific procedure. The areas over the menisci are felt and pain over the area could be a tear. This is a more basic procedure for diagnosis and only assists a physician with the initial prognosis of injury.

Even without tests, the physician could be able to diagnose the injury just by the location and the timing of the patient’s pain. Pain in the front of the knee is generally related to the patella. Pain inside the knee can be either a tear on the medial meniscus, or an injured medial collateral ligament. Likewise, pain on the outside of the knee can either be a tear on the lateral meniscus or an injured lateral collateral ligament. Finally, pain on the back of the knee is usually a cyst, particularly a Baker’s Cyst. Oddly enough, kneecap pain could also be felt on the back of the knee. The timing of the pain can also help the physician diagnose an injury. When the pain occurs while climbing down stairs, it is usually a kneecap problem, mostly chondromalacia and when the pain occurs during the morning, it is usually osteoarthritis.

The physician can also determine the presence of a meniscal tear through a process called Differential Diagnosis, also abbreviated DDx or ddx. Differential Diagnosis is basically a process of elimination. In Differential Diagnosis, a list of possible diagnoses is made, based on the current symptoms. As test results and new symptoms appear, individual or groups of diagnoses are eliminated until a single diagnosis remains. If no diagnoses remain, then either the physician made a mistake, or the patient’s true diagnosis was previously unknown to medicine before then. Differential Diagnosis allows the doctor to understand the patient’s condition, assess a reasonable and realistic prognosis, treat life-threatening conditions immediately and create an appropriate treatment plan for the patient. Specialized computer software has been developed to perform the Differential Diagnosis for the physician, such as QMR® and DiagnosisPro®, though a thorough knowledge of medicine and is still required to maximize the systems to produce accurate results.

Differential diagnosis basically uses a process of elimination where by possible causes of the injury are ruled out as new information comes to light and other symptoms are revealed. Differential diagnoses for meniscal tears include bone contusions, loose bodies, fractures in or near the knee, and discoid meniscus. Other diagnoses are plica syndrome, popliteus tendonitis, osteochondritis desiccans, pain and instability n the patellofemoral region, fat pad impingement syndrome, inflammatory arthritis, spraining in the meniscotibial ligament, synovial lesions, and chondral damage usually associated with trauma. Differential diagnoses for discoid meniscus include subluxation or dislocation of the patellofemoral joint, meniscal cysts, congenital subluxation of the tibiofemoral joint, subluxation and/or dislocation of the proximal tibial-fibular joint and snapping or tearing of the tendons around the knee due to osteophytes or arthritis. Discoid meniscus can also be a symptom of any condition that causes a snapping sound to come from the knee during a medical examination. DDx for a displaced meniscal tear include loose cartilage bodies, osteophytes, loose bone fragments from a fracture and ligament of Humphrey.

Via the use of the ddx diagnosis method the physician cannot accurately determine the presence of a meniscal tear, or if he cannot determine upon which meniscus the tear is located, the physician may call for an MRI to be performed on the patient. Magnetic resonance imaging, or MRI, is the most accurate noninvasive method for the diagnosis of meniscal tears. When taking an MRI, there are three fields of view that can be used. Sagittal images are taken from the side, coronal images are taken from the front or the back and transverse images are taken from the top or the bottom. With MRI, the number of arthroscopies performed for diagnosis has been reduced by at least one-third. MRIs can show the physician the location, shape, length, and severity of the meniscal tear. The images will allow the patient to know which, if any, surgical procedure is required and help them schedule it accordingly. This helps because the recovery period after a meniscal repair is longer than after a partial menisectomy (trimming away a portion of the meniscus).

Though MRIs are very accurate and can eliminate most chances of a misdiagnosis, there is still room for error. Known as false-positive MRIs, there are various conditions that may appear to be a meniscal tear on the MRI to all except very experienced physician. These include truncation artifacts, or Gibbs, vacuum-joint and magic-angle phenomena and intra-articular (within the joint) loose bodies that can obscure the edges of the meniscus. In vacuum-joint phenomenon, small pockets of intra-articular gas appear on the MRI and appear as holes. In magic-angle phenomenon, when a muscle made up mostly of highly structured water molecules, such as a tendon, is oriented at an angle, it appears gray in the MRI and give off increased signal intensity. Human error can also create a false-positive MRI. Errors made by the physician that could appear as a meniscal tear include misinterpretations of normal anatomic structure, older tears missed on a previous MRI and errors caused by a previous menisectomy or the misinterpretation of changes caused by a meniscal repair.

Two criteria have been developed to diagnose meniscal tears from MRI images. The first criterion is increased signal intensity within the meniscus, extending to at least one articular surface. If the abnormal signal intensity is present in two or more MRI slides, there is about a ninety-four percent chance of a meniscal tear, however if the signal is confined to only one slide, there is only about a fifty-five percent chance of a tear. The second criterion is an abnormal meniscal shape. In order to determine if this criterion is met, a thorough knowledge of anatomy is needed. Larger and more obvious tears can be seen on both sagittal and coronal MRI views. Smaller and less conspicuous tears can only be seen in one of the views however. The chance of a false-positive MRI decreases with the former situation.

If a serious meniscal tear has been diagnosed, or if the tear will not heal itself on its own, the orthopedic surgeon can choose to perform either an open surgery, or an arthroscopy to correct it. Open surgery for the treatment of meniscal tears is unorthodox and the procedure can only be performed on meniscal tears on the most outer periphery of the meniscus. This is due to the amount of exposure and accessibility caused by the open surgery. The benefit of open surgery is that it offers better preparation of the tear site. Most tears, however, can be corrected through arthroscopic surgery. Arthroscopy is a minimally invasive surgical procedure and it has the advantage of causing less trauma to the connective tissues at the incision site than open surgery. This will assist in speeding up the patient’s recovery time. The procedure is generally outpatient, however complications can occur that would result in the patient staying in the hospital. The anesthesia used during an arthroscopy can be either general or regional, depending on the patient’s choice and the severity of the tear and the length of the procedure. A recommendation will most often be made by the physician based on his experience and the patient’s medical history. The risks of an arthroscopic procedure are infection, bleeding, nerve damage, blood clotting, and complications resulting from the anesthesia such as allergic reactions, Malignant Hyperthermia, and relaxation of the heart and lungs, all of which could cause death.

Arthroscopies can also be performed for the examination and treatment of a damaged joint. A few small incisions are made at the joint to insert the arthroscope and the various surgical tools required for the procedures. The arthroscope is a type of endoscope that projects an internal view of the joint onto a screen. The surgeon uses this video feed to view and coordinate the operation. The other tools used during an arthroscopy are much smaller than normal surgical tools and are controlled either by foot pedals or manually by the surgeon. Once the incisions have been made, the joint is filled with irrigation fluid to distend the joint and create a larger surgical space. The fluid also increases the arthroscope’s visibility. Extravasation and edema can occasionally occur as the fluid leaks out of the surgical site and into the body. Extravasation occurs when the body’s cells swell from the water. Edema occurs when the cells burst. Finally, the tools are inserted and the surgeon performs the operation, repairing the damaged areas. The lateral meniscus usually tends to heal more quickly than the medial meniscus because it receives less stress them the medial meniscus. Meniscectomies are by far the most common arthroscopic surgery performed on a meniscal tears. During an arthroscopic meniscectomy, either a trimming tool or a biting tool is used to trim away the damaged portion of the meniscus and bringing it to a relatively smooth and stable rim. Obtaining a perfectly smooth rim was generally avoided as the meniscus will lose its grip on the joint and slide away. A partial meniscectomy involves removing only the torn piece of meniscus however; a total meniscectomy is the removal of the entire meniscus. If possible, the latter is most often avoided. Removal of the entire meniscus can later cause osteoarthritis in this area. Partial meniscectomies are successful around ninety-seven percent of the time while the success rate for complete Meniscectomies is difficult to gauge. Another difference between partial and complete meniscectomies is that partial meniscectomies have shorter operating times, a quicker recovery period for the patient, and a better assessment of the possible outcomes.

However, meniscal repairs are much more complicated and difficult; although repairs are successful almost ninety-five percent of the time. Tears over one centimeter in length occurring in or near the red periphery are the best candidates for a meniscal repair. Ideal repair candidates were also vertical, longitudinal tears occurring within three millimeters of the outer edge. During meniscal repairs, dissolvable sutures are used during a repair because they do not need to be removed manually and they allow the meniscus to heal more completely than with permanent sutures. The surgeon can choose between three different suturing techniques to repair a meniscus. The three techniques are inside-out, outside-in, and all-inside. With the inside-out technique, the surgeon uses zone specific cannulas to pass the sutures through the joint and hold the tear closed. A flexible needle is used and incisions are made at the back of the joint to attach the sutures to the capsule. A posterior retractor protects the neurovascular structures. The outside-in technique involves passing the sutures through the skin and spinal needles at the joint-line across the tear. The sutures are received through the joint and Mulberry knots are tied on the free ends. The excess portions are then tied to the capsule. An alternative form of the outside-in technique is to take the intra-articular portion, pass it over the tear a second additional time using a wire snare and tie it back on itself and onto the capsule. This alternative technique eliminates the use of Mulberry knots. The final technique is the all-inside technique, which is generally used on tears at the posterior meniscal horns. In the all-inside technique, an accessory portal is created in the back of the knee. The suture is then passed through the portal using a suture-hook device and tied intra-articularly.

A more complex and rare surgical procedure that can only be performed on injuries the result in an unrepairable meniscus is a full meniscal transplant, also known as a meniscal allograft. Finding a patient that would qualify as a perfect candidate for a transplant is difficult. The perfect candidate would be a young to middle aged patient who has had surgery for a meniscal tear before, has almost perfect cartilage lining in the knee, and can perform normally while missing a meniscus. The purpose of a meniscal transplant is to restore stability and provide cushioning to the area of a patient whose meniscus had to be removed and to prevent further degeneration of the other meniscus. This transplant procedure also helps to prevent future arthritis as some patients develop pain and friction within the area of the lost meniscus. In a meniscal transplant, a two to four inch hole is made in the tibia along with several smaller holes surrounding it. The new meniscus, which can either be taken from an organ donor (cadaver) or be synthetically created (scaffold), is then anchored into place and sewn down. If the donor’s meniscus was the correct size, then the surgery should be a success, however, between twenty-one and fifty-five percent of meniscal transplants fail in the first decade after surgery. Another risk of a meniscal transplant is that the donor meniscus could be infected with HIV/AIDS and hepatitis.

After such an operation it is imperative that the patient follows the doctor’s instructions. The surgeon will prescribe medications for pain and, in the case of a meniscal repair, a knee brace. Crutches only are needed during the first few days after the surgery, after which, most patients can return to work or school. It is imperative that the knee not get wet until the dressings are removed two to three day later, after which, patients should ice the knee a half hour every hour for several days to dull the pain. The patient can begin his regular diet almost immediately after surgery, although it is best if he or she starts off with clear liquids and then moves on to solid foods.  During the first month after the operation, patients are allowed to bend the treated knee up to sixty degrees and place weight on the knee only when standing. After the first month, the patient is allowed to bend the knee a little more and can now place weight on it even while it is not locked in extension. By the third or fourth month, crutches and knee braces are no longer needed and the patient can return to his normal activities, but is advised to slowly return to sports and other high-impact activities.

Exercise is also an important part of recovery after an arthroscopy as it restores strength, endurance, and range-of-motion to the knee, however; the preferred routine differs from doctor to doctor and also has to meet the patient’s specific needs. Most often, the patient is started with aggressive physical therapy sessions and as improvement is achieved, the sessions begin getting shorter, the patient is obligated to continue to exercise at home. Example exercises are quad sets, straight-leg raises, hamstring curls, heel raises, and shallow knee bends. Eight to twelve repetitions of each exercise at home will gently increase strength in the knee while in physical therapy, there are more exercises, and patients are asked to do more repetitions bringing some patients to tears. 

If the patient would prefer conservative treatment, or if they could not endure a surgical procedure, most doctors would recommend the RICE formula. RICE stands for rest, ice, compression and elevation. RICE should also be combined with NSTAIDS to dull the pain. NSTAID stands for non-steroidal anti-inflammatory drug. A common NSTAID used to prevent pain from meniscal tears in methylpredinsoline acetate mixed with lidocaine HCL. Many physicians in the past have used cortisone. Cortisone is naturally made in the body’s adrenal glands, but not in large quantities. Cortisone isn’t used as commonly now because of the cortisone flair it sometimes causes. Cortisone flair is crystallization of the cortisone and causes much greater pain then the injury it tried to heal. This can be alleviated and in some instances extinguished by icing. Over-the counter drugs, such as Aleve™ and Tylenol™, will also reduce pain and inflammation. Rest and anti-inflammatory medications reduce the painful symptoms of a meniscal tear and allow the patient to perform physical activity. Another treatment alternative is aspiration of the knee, which will drain the joint of fluid caused by swelling and also helps to dull the pain. The patient can still perform routine physical activity, within reason, but none the less is encouraged to enroll in physical therapy. Knee braces will increase stability in the injured leg and allow the patient to exercise the leg without irritating the meniscal tear. In severely injured knees, electrotherapy can strengthen the leg without requiring it to bend. Electrotherapy sends small amounts of electricity down to the muscles, causing them to twitch. The repeated twitching exercises the leg and the body’s response is to create more muscle cells to keep up with the demand. Several types of electrotherapy are ultrasound, laser therapy, transcutaneous electrical nerve stimulation, or TENS, and electrical muscle stimulation, known as EMS.

Other alternative treatments are also available to treat many knee conditions, including meniscal tears and the symptoms associated with them. Although many forms of alternative treatment have not yet been proven by science to be effective, many patients claim that they worked where conventional medicine had failed. Various herbs such as ginger root (Asarum canadense) and wintergreen mint (Gaultheria procumbens), when applied externally as pastes or oils, have been known to lessen pain and swelling. Other herbs, such as the Jamaican dogwood (Piscidia erythrina) can be helpful when used internally. Certain acupressure points such as Stomach Thirty-Six and Spleen Nine, located in between the tibia and the fibula, can relieve joint pain. Magnetic therapy has been reported to increase blood flow through the knee and peppermint oil could decrease inflammation through aromatherapy. The National Institute of Health has also found that acupuncture along the Large Intestine Meridian (along the left arm) can treat pain from osteoarthritis in the knee.  A vegetarian diet and certain massages can remove unhealthy chemicals from the knee and relax the muscles and tendons. Certain yoga positions, such as the Balasana (Child Pose) and the Paschimottasana can also help in strengthening the patient’s knee and stretching the muscles.

The most effective treatment for any injury is “prevention.” Especially in the cases of athletes or individuals who engage in aggressive and intense physical activity, implementing appropriate and responsible behavior is crucial. To prevent meniscal tears, the athlete should follow the standard protocol in preparing for a game, meet, or tournament. The most important action to take in preventing any injury during a sport is to warm up. Warming up is important for the athlete because it prepares the internal organs for long periods of strenuous activity, just as stretching and strengthening prepares the muscles for work. Another important step is to avoid any activity that causes pain. Balancing exercises will help the athlete increase his proprioception, or the body’s ability to know the location of its limbs. This prevents the athlete from falling or twisting his knee because of a misplaced step. Wearing the appropriate footwear and strapping will keep the knees stable and provide adequate cushioning in order to prevent the athlete from tripping and injuring his knee. Good shoes also help keep the soles of the feet from damage. Between training and the actual sport activity, it is also important for the athlete get enough rest to restore his strength. These steps simple steps will greatly assist the athlete in preventing a meniscal tear.

Although a good activity for stretching and warming up, athletes should also take caution if they practices yoga. Certain poses, such as Salamba Kapotasana, can tear the meniscus if they are performed incorrectly. The Salamba Kapotasana can injure the meniscus if the pose is entered into with haste. Yoga can accelerate existing damage to the medial meniscus. This pose should be entered slowly and it should be performed mildly. Any other pose that stretches the knee to its boundaries should also be used mildly, or the benefits will disappear and the poses will start to cause meniscal damage over time or in a severe traumatic rip. Poses that involve the entire upper body weight should be used with a block to sit upon, therefore, minimizing the actual impact on the joints. If these precautions are taken, yoga can help in preventing and healing a meniscal tear instead of causing one.

Through extensive research and analysis, it has been concluded that the severity of meniscal tears is directly related to how it was formed and the length of time that it was left untreated. Simple tears that are treated immediately are the least severe while displaced meniscal tears that are ignored for weeks or months are the most. In the former case, there should be a quick and full recovery. In the latter however, the patient may never experience a complete recovery. However, the patient should focus on preventing any knee injury instead of hoping for a mild instead of severe injury. If the patient is unlucky enough to damage his or her knee, great advances in the field of Orthopedics and a greater understanding of the human body has allowed doctors to treats meniscal tears and the great majority of each injury known to man much easier than even twenty years ago.



























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