meniscus tear

Meniscal tear: description

The menisci (gr. Mēnískos = moon-shaped body) are two ring-shaped cartilages that lie at the side of the knee between the bones of the upper and lower leg. They act as shock absorbers, that is, they increase the contact surface and reduce the friction between the bones. The menisci thus allow a sliding, painless movement in the knee joint. At least, as long as there are no cracks in the tissue, the so-called meniscal tear.

In particular, the inner and outer meniscus are distinguished in the knee joint. The medial meniscus is crescent-shaped and relatively immobile, because it is firmly attached to the inner ligament (collateral ligament). The result: He can not avoid acting forces so well and therefore tears easier. In contrast, the lateral meniscus has an approximately circular shape and is less fixed to the surrounding tissue. He therefore has a greater range of motion in force, a meniscal tear occurs less often in him.

Typically, a meniscus injury happens especially in rotary-fall injuries (Traumatic)For example, in sports such as skiing or football. But a meniscal tear also occurs at Age-related wear or one chronic overload the knee joint, for example, in some occupational groups with predominantly squatting activity, such as tilers.

A meniscal tear can pull through the tissue in all directions. In addition to the shape of the tear, it is crucial for the choice of therapy at which point the tear in the meniscus is located. A suture is often possible in the well-perfused outer zone, while in the poorly perfused inner zone, the injured meniscal component often has to be removed.

A meniscal tear is relatively common, affecting about 160 out of every 10,000 people. Not every meniscal damage causes acute discomfort or pain. Depending on the size and extent of the tear, various symptoms may occur that impede the affected person differently. The treatment of the meniscal tear depends on this: In cases with no or limited restrictions, a meniscal tear is treated conservatively (without surgery). In severe cases, surgical therapy or an artificial meniscus may be necessary.

Meniscal tear: symptoms

You can read all about the typical signs of a meniscal tear in the article Meniscal Tear – Symptoms.

Meniscal tear: causes and risk factors

A meniscal tear can have different causes. About half of all cases of meniscal injury are due to regression (degeneration) of the cartilage tissue. The other half is caused by acute injuries, often with an already damaged meniscus.

degeneration

Meniscal degeneration is an increasing structural weakness of the fibrocartilage from which cartilage disks are built. Due to wear, a meniscus is less resistant to force, so a meniscal tear can occur. Such a cartilage wear is normal after a certain age. However, certain occupational groups with increased knee strain are at greater risk of meniscal tear. These include athletes, construction workers, gardeners or tilers.

injury

A strong vertical load (for example, when jumping from low altitude) can cushion the menisci well. However, if the force acts obliquely from the side on the fibrocartilage, it becomes overstretched and can tear. Typical triggers of a meniscal tear are rotary-fall injuries, for example when skiing or football. In such accidents, the meniscus is fixed by body weight while at the same time the foot is twisted. This can lead to a meniscal tear, especially if the meniscus is damaged. Meniscus damage can also occur in everyday life, simply when “walking in a squat”.

Even direct impact on the entire knee can lead to a meniscal tear. Physicians then speak of a primary traumatic meniscal tear. Knees, adjacent bones and menisci, for example, can be damaged together when falling from a great height.

In very rare cases, a meniscal tear occurs due to genetic changes in form. An example of this is the so-called disk meniscus, in which one or both Menisci not as usual have an annular structure, but are a plate disc. This is increasingly loaded with each movement and thus wears faster.

Meniscal tear: examinations and diagnosis

The right contact for suspected meniscal tear is your GP or a Specialist in Orthopaedics, Not every meniscal tear necessarily causes symptoms that severely affect the person affected. Smaller cracks are not noticed in many cases and grow again by themselves.

The doctor’s visit usually begins with the fact that you tell the doctor your current symptoms and any previous medical conditions (anamnesis). Possible questions from the doctor could be:

• Do you have pain? If so, where exactly and in which movements do these occur?
• How long have you had these complaints?
• Do you play a lot of sports or can you remember an event in which your knee was extremely stressed?
• Do you practice a job that puts heavy strain on your knees?
• Have you been operated on the knee?

Physical examination

After the medical history follows the physical examination. If there is a suspicion of a meniscal tear, various tests are available (meniscus tests) to determine which meniscus may be injured. In the tests of Steinmann, Apley – Grinding, Böhler, McMurray and Payr, the doctor moves the lower and thighs. He charged each of the inner or outer meniscus. Depending on which position hurts, the doctor can close the site of the injury. It is true that the inner meniscus is significantly more affected by damage than the outer meniscus. If meniscal pain occurs, the suspected diagnosis “meniscal tear” is confirmed by further examinations.

During the physical examination, the doctor also checks if a joint has formed (“dancing patella”), if the palpation of the knee joint gap is painful and if there are problems with stretching the leg (stretching inhibition, typical for the “basket handle tear”, see above).

Further investigations

Meniscal tear: MRI
Magnetic resonance imaging (MRI) is the most important study in suspected meniscal tear. Here, the soft tissue of the knee (ligaments, menisci, muscles, etc.) is displayed in high resolution in a sectional view. A healthy meniscus appears on MRI as a completely black structure. In the case of cartilage wear, lighter spots and, in the case of a tear, a clear, light streak can be seen in the image. With an MRI you can better assess the extent of the damage and the location of the exact meniscus injury.

Meniscal tear: Arthroscopy
In arthroscopy, a tiny camera is inserted into the knee joint to examine the structures of the knee. For this purpose, a small incision is made under local anesthesia, through which a rod-shaped instrument is pushed into the knee. On this rod, a light source and a camera are attached, which transmit the images from the knee joint live on a monitor. Another cut introduces a small heel that tests the condition and functionality of the menisci and ligaments in the knee.

The advantage of arthroscopy over MRI is that in arthroscopy, meniscal damage can be treated immediately in the same procedure. In addition, detached meniscus parts can be removed from the joint space immediately, especially in a Korbhenkelriss.

Differentiation of different forms during meniscal tear
An MRI or arthroscopy can be used to determine where the meniscus is injured. The therapy depends on the localization and the course of the tear. Depending on the following types of meniscal tear are distinguished:

• Longitudinal crack: The tear is parallel to the grain of the meniscal cartilage.
• Bucket-handle tear: Special form of longitudinal crack, in which the meniscus is split by a longitudinal crack. Often very painful.
• Radial crack (transverse crack): The tear is transverse to the grain of the meniscal cartilage.
• Lobe rupture (tongue tear): The crack begins in the inner zone of the meniscus and extends from there to the outer zone. Often due to degenerative predation.
• Horizontal cracks: The crack is located in a sense in the middle of the meniscus and splits this fischmaulartig in an upper and lower “lip”.
• Complex crack: Combination of different meniscus rips.

Supplementary examinations:

X-ray
In an X-ray examination, especially changes in the bones become visible. It is useful in individuals who are suspected of having joint degeneration (osteoarthritis) in the knee or bone damage. The X-ray examination is usually made after a fall or an injury with subsequent pain.

ultrasound
An ultrasound examination (sonography) can also be used to determine if the ligaments that hold the knee stable around the menisci are also damaged. A knee joint effusion can also be detected by ultrasound. The ultrasound examination is not a standard examination and is only performed if the symptoms suggest further damage outside of the menisci.

Meniscal tear: treatment

The treatment of the meniscal tear depends on the size of the tear and the existing pain. In principle, it is best to have self-treatment (“first aid”) immediately after an accident and the suspected meniscal tear. So the extent of the damage and the pain are kept small. If the symptoms persist, a medical examination and treatment are recommended in any case.

Decisive for the therapy is not only the tear form, but above all, whether this Crack in the inner or outer zone the meniscus is located. While the outer zone (-> skin direction) is well supplied with blood, the inner zone (-> towards the middle of the knee) is hardly supplied with blood. Meniscal damage in the outer zone can therefore often be sutured because healing of the suture has a chance of success. In the case of a meniscus injury of the inner zone, however, healing of the damage does not have a good chance, so the injured meniscus component must be surgically removed.

First aid

If a meniscal tear occurs during sports or during a trip, you should immediately cool the knee, for example with ice packs or envelopes with cold water. Do not lay the ice directly on the skin, but wrap it in a soft cloth. Store your leg up and move it as little as possible. These measures reduce the swelling of the knee. In case of existing pain you should definitely consult a doctor after the first treatment. In addition to a meniscal tear, injuries to the cruciate ligaments, lateral ligaments, kneecap, etc. can be responsible for the pain.

Conservative treatment

Not every meniscal damage requires surgery. Small tears in the well-perfused outer zone of the meniscus can often be treated without surgery. A so-called conservative (non-surgical) therapy is also possible if already in the knee regression (degeneration) of the bone or a significant joint wear (arthritis) are detected. Conservative therapy is composed of:

• pain medication
• Injection of anti-inflammatory substances (such as cortisone) into the joint space
• cooling
• protection
• Physiotherapeutic exercises with muscle building

Whether the therapy is successful depends on the size of the damage, any previous damage in the knee and the individual stress requirements in everyday life. In uncertain cases, treatment with a conservative therapy may be attempted and in case of failure, may still be switched to an operative treatment.

Meniscus tear surgery

Everything important for the meniscal tear operation can be read in the article Meniscus-OP.

Meniscal tear: duration

A generalized prognosis of meniscal tear duration is not possible, since in the individual case it depends on the size of the tear and the extent of the damage. After surgery, it takes about six weeks for you to be able to relieve your knee. However, you should do sports only after earliest three months of close season. If a conservative therapy is possible, the cure takes a few weeks to months.

Meniscal tear: Disease course and prognosis

In any case, it makes sense to have a meniscal tear treated professionally. At the very least, after you notice any signs of knee problems, you should have the cause and possible further development cleared up by a specialist. An untreated meniscal tear can become progressively larger over time and also damage other structures in the knee (ligaments, articular cartilage).

A general prognosis can not be made because of the variety of the disease. Minor damage usually heals with conservative treatment and protection on its own. However, especially for athletes and certain occupational groups, the load on the knees is so great that it can come at any time after a healed meniscus tear again to meniscus damage.

After a meniscal tear, you should first gently re-strain your knee. Doctors and physiotherapists can show you specific exercises that strengthen the muscles around the knee and slowly restore the menisci to the strain. After an operation, the load capacity is usually restored after about six weeks, after a small meniscal tear healing can also be faster.

In any case, you should seek personal advice from a doctor before you actively participate in sports. In severe cases, stressful sports such as football or skiing generally have to be avoided meniscus tear or to avoid another meniscal damage.