When we feel knee pain, it is, mostly, related to the meniscus. Since the meniscus is a thin cartilaginous layer, it can be damaged easily. Pain in the knee may be a sign of a few types of injuries and improper functioning of the meniscus. A meniscus tear, chronic disorders, and a sprain of the intermenal ligaments can have various symptoms, as well as treatment methods are also different. So, how can we diagnose the causes of meniscus pain correctly? What are the treatments?
A meniscus of the knee is a cartilaginous formation located in the joint cavity that serves as a shock absorber, or a stabilizer, to protect the articular cartilage.
There are two menisci in the knee: the inner (medial) meniscus and the outer (lateral) meniscus. A torn internal meniscus of the knee joint is more common, due to its lower mobility. The symptoms of a meniscus injury are limited joint mobility, knee pain, and, in advanced cases, arthritis of the knee.
A sharp, stabbing pain, swelling of the joint, difficulties when moving limbs and a painful clicking in the knee indicates a possible meniscus tear. These symptoms occur immediately after an injury and can be also related to other joint damages. More reliable symptoms of a torn meniscus appear in 2-3 weeks after injury. With such traumas, there is a localized knee pain, accumulation of fluid in the joint cavity, locked knee, and weakness of the anterior thigh muscles.
To diagnose the torn meniscus more reliably, you need special tests. There are a few bending tests (Landa, Baikov, Rocher, etc.), when with a certain degree of joint straightening you feel pain. Rotational tests are based on the revealing of symptoms while rotating the joint (Bragard test and Steinman test). It is also possible to diagnose meniscus tear by compression symptoms, as well as by mediolateral tests and MRI.
Treatment techniques for damaged meniscus are different, depending on the severity and a type of injury. Classical methods are rather universal and can be applied for any type of injury.
First of all, you receive an anesthetic injection to eliminate pain, then, the joint is punctured, accumulated blood and fluid are removed from the joint cavity, and locked knee symptoms are eliminated, if any. After all those procedures, the joint needs a complete rest, for which a plaster cast or an orthosis is applied. Mostly, 3-4 weeks of immobilization are sufficient, but, in severe cases, you may need up to 6 weeks for recovery. It is recommended to apply cold locally and take non-steroidal medications to relieve inflammation. Later, exercise therapy is recommended, as well as walking with braces and physiotherapies.
Inner meniscus tear is the most common injury of the knee joint. There is a traumatic tear and degenerative tear of meniscus. Traumatic tears occur mostly in athletes, young people 20-40 years old, but without treatment, they can transform into degenerative meniscal lesions that are more common in the elderly.
Based on the location and shape, there are several major types of meniscus tear: a bucket-handle tear, transverse tear, longitudinal tear, flap tear, horizontal tear, an anterior or posterior meniscus horn tear, and paracapsal injuries. Traumatic tears are usually vertical: oblique or longitudinal. Longitudinal vertical tears, or bucket-handle tears, can involve either entire meniscus or a part only. They often begin from damage of the meniscus posterior horn.
Let’s consider the tear of the posterior horn of the medial meniscus. Injuries of this type occur most often, since the majority of the longitudinal, vertical tears and bucket-handle tears begin from the damaged horn of the meniscus. With long tears, there is a high probability that a torn part of the meniscus will impede the movement of the joint, causing painful sensations and leading to a joint locking. Combined meniscus tears, that include both an injury and degenerative symptoms, may occur at several sites, but, mostly, they are localized in the posterior horn of the meniscus, and, as a rule, happen in elder people with degenerative age changes in the meniscus. When the damaged posterior horn of the medial meniscus does not involve a longitudinal cleavage and cartilage displacement, you may be under a constant threat of locked joint, but it never happens. The anterior horn of the medial meniscus is not so often torn.
A tear of the posterior horn of the lateral meniscus occurs 6-8 times less often than that of the medial one, but it leads to the same negative consequences. The adduction and internal rotation of the tibia is the main cause of tears of the external (lateral) meniscus. The outer side of the posterior horn of the meniscus is in the most danger of this kind of damages. A tear of the arch of the lateral meniscus with displacement, in most cases, leads to difficulties in the final stage of knee extension, and, sometimes, causes a joint locking. The tear of the lateral meniscus can be recognized by a specific popping sound during the rotation movements inward.
Torn Meniscus Symptoms
The symptoms of torn meniscus can be quite different. A meniscus tear can be acute (traumatic) or chronic. The main sign of the tear is joint locking. If there is no locking it is quite difficult to diagnose a torn medial or lateral meniscus immediately after a trauma. After a while, the tear can be identified by infiltration in the area of the joint space, local pain, and also with help of pain tests that are suitable for any kind of meniscus injury.
The main symptom of meniscus tear is pain when the joint space is palpated. Special diagnostic tests have been developed, such as the Apley grind test and McMurray test. The McMurray test is performed in two ways.
In the first case, the patient lies on the back with a leg bent in the knee joint at an angle about 90°. Then, an examiner holds and palpates the knee with one hand, whilst another one produces the rotational movements of the shin, first, out, and, then, inside. In case of painful clicks and cracks, we can assume a pinching of the meniscus between articulate surfaces, and a test result is considered positive.
The second version of the McMurray test is a flexion test. It is performed in the following way: with one hand, a doctor clasp the knee same as in the above example, then the leg is bent in the knee as much as possible; after this, the shin is turned out to reveal a possible tear of the inner meniscus. Provided that the knee is slowly extent to about 90° and rotated, in case of the meniscus tear, the patient feels pain in the joint in the anterior and posterior regions.
During Apley grind test, a patient lies on the stomach and flexes the leg in the knee at an angle of 90°. With one hand, a doctor presses the patient’s heel, whilst his other hand rotates the foot and shin. If there is a pain in the joint space, the test is considered positive.
Torn Meniscus Treatment
The torn meniscus is treated both with conservative and surgical methods (resection of the meniscus, complete or partial, with the following restoration). With the development of innovative technologies, meniscus transplant surgery is growing popular.
Conservative treatment is mainly used for small tears of the meniscus horn. These injuries are often painful, but do not cause the pinching of the cartilage or produce clicks and popping sensations between the articular surfaces. This type of tears pertains to stable joints. The treatment is avoiding the sports with active movements, especially those that require leaning on one leg on the ground and involve jerks, as such activities can worsen the condition. In older people, such treatment leads to positive results, as the cause of their symptoms are often caused by tears of degenerative nature and arthritis. Small longitudinal tears of the medial meniscus (less than 10 mm), not penetrating tears of the lower or upper part of the meniscus, transverse tears of not exceeding 3 mm often can heal by their own or even do not show any symptoms.
Meniscus operation is one of the most widespread surgeries in Germany. The main goal of this operation is to restore mobility of knee joint. Surgeons use scalpels in order to restore anatomical structure of meniscus to fix it as much as possible. However, surgical treatment is not always obligatory. In many cases, conservative therapy is more than enough. Here’s some important information concerning surgical treatment methods for meniscus.
When surgical treatment of meniscus is required?
Specialists’ opinions differ, when it comes to pros and cons of meniscus surgery. Some doctors claim that meniscus surgery is obligatory even in case of minor traumas. Vice versa, others suppose that operation is not necessary, if meniscus damage is not highly pronounced. Of course, there’s no point in basing on one certain opinion, because the selection of treatment type depends on many different factors and the situation itself, and there are no versatile general recommendations for treatment. Choice of treatment and therapy depends on patient’s age, pain sensations and the degree of meniscus flexibility. The aim of any meniscus operation is full recovery of functions.
Treatment of meniscus damage without surgical invasion
Sometimes traumas of meniscus can be treated without surgical invasion. This is the case when a person deals with small cracks. Traumas in meniscus zone with good blood supply (exterior edge of meniscus in joint capsule) can simply recover themselves. In this case, doctors recommend conservative treatment. A patient needs to use pain killing ointments, cortisone injections (hormonal medication) and go through physical therapy. During the first days after surgical invasion, it’s necessary to avoid physical loading on knee joint. In a few weeks, physical load can be gradually introduced starting from simple exercises. Your doctor or physical therapy specialist will tell you which exercises can be performed at home. Meniscus damage can be treated by a conservative way, if degenerative changes caused it. If a doctor examining the images will find out that some parts of meniscus were separated and are located in articulate gap, surgical invasion cannot be avoided.
Prior to meniscus surgery
Prior to surgical invasion in meniscus, knee joint should be thoroughly examined. Together with physical examination, doctors need to diagnose the condition with MRI (magnetic resonance therapy). Looking at the images, the doctor can define where exactly the damage is located. Besides, he can define whether cartilage and connective tissues have been damaged. After analyzing the results of MRI, the doctor will figure out an appropriate treatment variant. In many cases, arthroscopy shows the type and degree of damage. Your surgeon will recommend a suitable treatment method for your exact situation.
Methods of meniscus surgery
Today, there are two main types of meniscus surgery: arthroscopic surgery, and open meniscus operation. A few years ago, all patients had to go through operation, while today surgeons and patients prefer arthroscopy in the vast majority of cases. Surgical invasion is performed under local or general anesthesia.
Arthroscopy is a minimally invasive method of diagnostics and treatment of joints with the help of an optimal instrument. When this type of treatment is used, a surgeon does not make huge cuts – two or three small incisions are made instead. The first incision serves to input a rod-shaped camera that will transmit the image inside patient’s body on a monitor. Other incisions are used to input surgical instruments using which the surgeon will remove damaged parts of meniscus.
The main advantage of arthroscopy is that smaller incisions regenerate faster and don’t live noticeable scars after operation.
In some cases, open meniscus surgery is preferable to arthroscopy. Open method is used, for instance, to treat meniscus break and damage of ligaments in the knee joint or joint capsule. In case of open surgery method, a surgeon make a 5 cm wide cut that is fully stitched after the operation. Stitches are removed in 10 days after the operation.
Meniscus surgery: surgical methods
No matter which type of operation is performed – arthroscopic or open one – the following surgical methods are used for meniscus treatment:
- Refixation of meniscus (stitch on meniscus)
- Partial removal of meniscus (partial resection of meniscus)
- Meniscus replacement (total removal of meniscus with replacement)
Refixation of meniscus (stitch on meniscus)
In case of meniscus resection, destroyed tissues are cut out, and healthy ends are stitched together. After meniscus fixation, doctors take measures aimed at regeneration of damaged tissues.
Meniscus resection is performed only in cases when minor part of meniscus is damaged, and its tearing did not spread all along its length, and meniscus is still connected with the capsule that’s supported by blood vessels. If the main part of meniscus is preserved, resection will give positive results and timely recovery and restoration of all anatomical structure. Unfortunately, this method cannot be applied in case of massive damage, or if meniscus is not supplied by blood sufficiently.
After meniscus fixation, knee joint should be moved very accurately during several weeks so that meniscus tissues would regenerate properly. General physical loading is introduced gradually. During the first days after operation, a patient needs to wear a splint. In three weeks, light physical load on knee joint can be introduced. In two months, a patient can practice some kinds of sports: swimming, cycling and even strength training.
Meniscus surgery: meniscus resection
In case of meniscus resection, only its destructed part is removed (partial meniscus resection), or the entire meniscus is removed (total meniscus resection). Meniscus resection is applied in case when meniscus tissues are destroyed, when there are degenerative changes in knee joint, or when damaged meniscus hasn’t regenerated, and its torn parts are not supplied by blood vessels. Meniscus resection can be performed in outpatient basis, and patient can go home right after the operation. After the operation, a patient needs to go through physical therapy. If patient’s work doesn’t require physical activity, he can start it in one-two weeks.
The most popular and efficient operation is meniscus replacement. During this operation, the damaged meniscus is removed, and a model made of polyurethane resin, collagen, or human meniscus (transplantation of meniscus) is placed instead of it. Prior to implantation of meniscus, the doctor will fully adapt it to the form and size of patient’s meniscus. Implantation is a minimally invasive procedure that can be done with the help of arthroscopy.
The main advantage of meniscus resection is its ability to regenerate, because fibers can be restored. The main disadvantage of this procedure is a long recovery period that can last up to 2-3 months. Even today, doctors cannot guarantee precise results of tissue recovery. Meniscus resection is not a standard type of operation.
Implantation of donor’s meniscus is recommended for young patients who suffer from arthritis of knee joint, or have some other problems with knee joints. As a rule, people who died in accidents but preserved meniscus tissues become donors of meniscus.
Like any other operation, meniscus surgery has some risks. For instance, it can lead to serious bleeding. Besides, bacteria can get into the wound and cause infectious process. Inflammatory process caused by infection is a serious complication, because it can lead to destruction of knee tissues. However, infections rarely occur during meniscus surgery, because surgical invasion is performed in sterile conditions.
In rare cases, pain can stay after meniscus surgery, or appear some time later. There’s also a small risk that meniscus won’t be able to bear the loading. Sometimes, operated meniscus can develop exudate that can be removed only by puncture of knee joint. Before the operation, a doctor will warn the patient that there’s a risk of secondary meniscus tearing, which means the operation may need to be performed again.
Weigh the risk-benefit ratio thoroughly
Based on their data, the authors of the study recommend that consideration be given to the duration of the symptoms and the presence of osteoarthritis when deciding on a meniscal operation. And in the operation itself, the size of the procedure should be reconsidered in terms of prognosis. However, according to the researchers, a worse outcome is not necessarily synonymous with an unsatisfactory result: "It just means that a patient-relevant outcome in the presence of a specific factor is worse than in the absence of this factor."
More recently, a study by researchers at Nijmegen University had suggested that patients suffering from knee arthrosis and undergoing surgery for a meniscal tear later required joint replacement more frequently than patients who did not undergo surgery. However, this was just a retrospective observational study. In this type of study it can not be ruled out that other factors influenced the results. Thus it could be that the operated patients had certain factors even without the intervention, which would have made an endoprosthesis faster necessary.
Overall, however, it has become clear that the benefit-risk balance needs to be analyzed when choosing treatment for meniscal damage. Under certain circumstances, a targeted physiotherapy, by which the muscles are strengthened and the knee joint is stabilized, be more useful than surgery.
In most cases, meniscus surgery can be performed on outpatient basis, which means the patient can go home the same day. Depending on the type of surgical invasion and scale of meniscus damage, it can require a short or a long recovery period.
After meniscus fixation, a few months can be required for recovery without any physical loading on the knee. If you start loading knee joint earlier, wholeness of scars will be disturbed, which may slow down recovery process. Doctors recommend following spare recovery process that can take from 2 to 3 months until scars grow fully, and the tissue becomes as flexible as before meniscus operation. If a part of meniscus has been removed, a patient can bend and unbend the knee in a few days. Patients are always warned that recovery period requires several weeks.
After meniscus operation, a person has to go through an individual course of physical therapy that will adapt knee joint to physical load and strengthen muscles. The exercises used for physical therapy help patients to rehabilitate quickly in the future. After successful meniscus operation, a patient can return to active, fully-fledged life, if doctor’s recommendations for rehabilitation period are followed.
A meniscal tear is one of the most common reasons for surgical interventions in Germany. But not always an operation is necessary. Researchers have now identified factors that influence the success of surgery after a meniscal injury.
While a knee operation the whole meniscus or parts of it will be removed, it is called a (partial) meniscectomy. With special instruments while the torn portion is smoothed. The goal is to fully restore the mobility in the knee. But the operation is not always the right choice for a meniscal tear. For example, studies have shown that one year after surgery, pain is rarely lower than without surgery. Researchers at the University of Rotterdam have now investigated which patients are likely to benefit from partial meniscectomy and which are not. In a systematic review, they identified three factors that statistically significantly influence the chances of success of an OP.
Three factors significant for success of meniscus surgery
The scientists around Susanne Eijgenraam evaluated 32 studies with a total of 4250 patients for their analysis. However, the quality of the studies was inconsistent and the evidence of the results was only moderate. Thus, only one study was randomized-controlled, four were prospective and the others retrospective. The follow-up period was at least one year each.
It turned out that three parameters were statistically relevant for the success or failure of an OP. Thus a longer duration of the complaints (over three and / or over 12 months) accompanied with a worse result. In patients with a history of knee osteoarthritis, a lesser improvement was achieved than without. And a larger meniscus resection tended to have worse chances of success.
On the other hand, there was no influence on the result before the operation or the type of tear. Even the assumption that the procedure was less promising for degenerative meniscal lesions could not be confirmed in this analysis.