Brief overview
- Treatment: First aid measures (cooling, elevation), painkillers, rest, physiotherapy, possibly surgery
- Symptoms: Pain when moving the knee joint and when pressure is applied, fluid accumulation in the joint, in severe cases it is not possible to stretch the leg
- Causes and risk factors: falls, usually during a twisting movement in the knee, force, wear and tear, overloading
- Progression and prognosis: The progression depends heavily on the type and location of the meniscus tear, but it is generally important to protect the leg and seek medical help.
- Prevention: Age-related wear and tear can only be prevented to a limited extent. Those affected should avoid activities and sports that put strain on the joints.
What is a meniscus tear?
A distinction is made between the medial and lateral meniscus in the knee joint. The inner meniscus (medial meniscus) is crescent-shaped and relatively immobile because it is firmly attached to the medial collateral ligament. It is therefore not well able to evade the forces acting on it and therefore tears more easily.
Typically, a meniscus injury occurs primarily in the event of a fall injury in which the knee twists. Such traumatic meniscus damage often occurs during sports such as skiing or soccer. However, a meniscus tear also occurs as a result of age-related wear and tear or chronic overloading of the knee joint, for example in some occupational groups with predominantly squatting activities, such as tilers.
Not every meniscus injury causes acute discomfort or pain in the knee. Depending on the size and extent of the tear, different symptoms occur, which affect those affected to varying degrees. The treatment of the meniscus tear depends on this: In cases with no or minor restrictions, a meniscus tear can be treated conservatively (without surgery). In severe cases, surgical treatment or an artificial meniscus may be necessary.
The meniscus tears in different ways. This is why doctors distinguish between different forms of meniscus damage:
- Longitudinal tear: The tear is parallel to the fibers of the meniscus cartilage.
- Basket handle tear: Special form of longitudinal tear in which the meniscus is literally split. This meniscus tear extends from the anterior part (anterior horn) to the posterior part of the meniscus (posterior horn) and is often very painful.
- Flap tear (tongue tear): The tear begins in the inner zone of the meniscus and extends from there to the outer zone. Often due to previous degenerative damage.
- Horizontal meniscus tear: The tear is located in the center of the meniscus, so to speak, and splits it into an upper and lower “lip” like a fish mouth.
- Complex tear: Combination of different types of meniscus tear with more than one main direction of tear.
How is a meniscus tear treated/operated on?
The decisive factor for treatment is not only the shape of the tear, but also whether the tear is located in the inner or outer zone of the meniscus. While the outer zone towards the skin is well supplied with blood, the inner zone towards the center of the knee is hardly supplied with blood. If there is meniscus damage in the outer zone, it is therefore often possible to suture it. Due to the good blood supply, there is a high probability that the tear will heal again.
First aid: what to do in the event of a meniscus tear
If a meniscus tear occurs during sport or an outing, the affected knee should be cooled immediately, for example with ice packs or cold water compresses. The ice should not be placed directly on the skin, but wrapped in a soft cloth. It is advisable to elevate the leg and move it as little as possible. These measures will reduce the swelling of the knee.
Conservative treatment for meniscus tears
Surgery is not necessary for every meniscus injury. Small tears in the outer zone of the meniscus, which is well supplied with blood, can often be treated without surgery. Conservative (non-surgical) therapy is also an option if there is already evidence of bone degeneration or significant joint wear (osteoarthritis) in the knee. Conservative therapy consists of
- Pain medication
- Cooling
- Rest
- Physiotherapeutic exercises with muscle building
Whether the therapy is successful depends on the extent of the damage, any previous damage to the knee and the individual load requirements in everyday life. In uncertain cases, the doctor may initially try conservative therapy and switch to a surgical treatment method if it is unsuccessful.
How is a meniscus tear operated on?
In particular, if parts of the meniscus have become detached from the tear and are located in the joint space, there is usually no way around meniscus surgery. The aim of such an operation is to preserve as much meniscus tissue as possible and restore as much mobility as possible.
Open surgery and arthroscopy for meniscus tears
The advantage of arthroscopy is that the minor injuries to the skin heal more quickly and no large scar remains after meniscus surgery. The open method is an option, for example, if not only a meniscus tear is to be treated but there is also damage to ligaments in the knee joint or to the joint capsule.
Surgical techniques for meniscus tears
- Meniscus replacement (insertion of an artificial meniscus): In meniscus replacement, the doctor removes the damaged meniscus completely and inserts an artificial replacement model instead. As there is not yet sufficient study data available to definitively assess the quality of this procedure, meniscus replacement is not yet a standard procedure in meniscus tear therapy.
What are the symptoms of a meniscus tear?
Depending on which meniscus is injured, the pain can be localized more to the side (lateral) of the knee or to the inside (medial).
Meniscus tear symptoms when the outer (lateral) meniscus is damaged:
- Pain when turning the knee inwards (internal rotation)
- Pressure pain at the lateral knee joint gap (this can be felt with the fingers)
- Pain when squatting down
- Possibly pain when stretching the leg
Meniscus tear symptoms with damage to the inner (medial) meniscus:
- Pain when turning the knee outwards (external rotation)
- Pressure pain at the medial knee joint gap (this can be felt with the fingers)
- Pain when straightening up from the squatting position
- Pain when bending the knee
Effusion with meniscus tear
Serious meniscus tear symptoms
Meniscus tear symptoms with chronic progression
The pain is often sometimes stronger and sometimes less pronounced. There is a risk that those affected will not recognize these as symptoms of a meniscus tear and therefore do not take it easy or consult a doctor. The longer a meniscus tear remains untreated, the more the damage spreads.
Those affected who notice such complaints repeatedly should consult a doctor. With timely treatment, it is often possible to preserve the meniscus. In the case of advanced meniscus damage, this is often not the case and meniscus removal is necessary.
Causes and risk factors
Degeneration
Doctors define meniscus degeneration as an increasing structural weakness of the fibrous cartilage that makes up the meniscus. Due to wear and tear, the cartilage tissue is less resistant to the effects of force and therefore more susceptible to a meniscus tear. Such cartilage wear is quite normal from a certain age.
Injury
The menisci are able to absorb a strong vertical load (for example when jumping from a low height) well. However, if the force acts on the fibrocartilage tissue at an angle from the side, it overstretches and may tear.
In addition, in some cases, direct violence to the entire knee leads to a meniscus tear. Doctors then speak of a primary traumatic meniscus tear. For example, if you fall from a great height, it is possible for the knee, adjacent bones and menisci to be damaged together.
Examinations and diagnosis
The right people to contact if a meniscus tear is suspected are your family doctor or an orthopaedic specialist. Not every meniscus tear necessarily causes symptoms that severely affect the affected person. Smaller tears often go unnoticed and grow back on their own.
- whether there is pain and where exactly and with which movements it occurs,
- how long the pain has been present
- whether there was an event, for example during sport, in which the knee was subjected to unusually high stress,
- whether the knee is exposed to heavy strain for professional reasons and
- whether knee surgery has already been performed.
Physical examination
In the Steinmann, Apley-Grinding, Böhler, McMurray and Payr tests, the doctor moves the lower leg and thigh. In doing so, he puts pressure on the inner or outer meniscus. The painful position allows conclusions to be drawn about the location of the damage. The inner meniscus is significantly more frequently affected by damage than the outer meniscus. If meniscus pain occurs, the doctor will confirm the suspected diagnosis of “meniscus tear” with further examinations.
Further examinations: MRI and arthroscopy
Meniscus tear: MRI
Magnetic resonance imaging (MRI) is the most important examination for suspected meniscus tears. It shows the soft tissue of the knee (ligaments, menisci, muscles, etc.) in high resolution in a cross-sectional image. A healthy meniscus appears in the MRI as a continuous black structure. In the case of cartilage wear, lighter patches can be seen in the image and in the case of a tear, a clear light stripe.
- Grade 1 (punctiform MRI signal in the meniscus interior without contact with the surface): degenerative damage in the meniscus interior
- Grade 2 (linear MRI signal in the meniscus interior without contact to the surface): degenerative damage or tear in the meniscus interior
- Grade 3 (signal with contact to the surface of the meniscus): complete tear of the meniscus
Meniscus tear: Arthroscopy
The advantage of arthroscopy over MRI is that meniscus damage can be treated immediately in the same procedure if necessary. It is also possible to immediately remove detached parts of the meniscus from the joint space, particularly in the case of a basket handle tear.
Additional examinations:
X-ray examination
Ultrasound examination
During an ultrasound examination (sonography), the doctor determines whether the ligaments that keep 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 carried out if further damage outside the menisci is likely based on the symptoms.
Course of the disease and prognosis
A general prognosis is not possible due to the diversity of the disease. Minor damage usually heals on its own with conservative treatment and rest. However, athletes and certain occupational groups in particular put so much strain on their knees that meniscus damage is possible again at any time after a healed meniscus tear.
How long does a meniscus tear take to heal?
It is not possible to make a generally valid prognosis as to how long a meniscus tear will last. How long those affected by a meniscus tear are ill depends on the size of the tear and the extent of the damage. After a meniscus tear operation, it takes around six weeks before those affected can put weight on their knee again.
Prevent
Those affected who wish to return to active sport should always seek personal advice from a doctor. In severe cases, it is advisable to generally avoid strenuous sports such as playing soccer or skiing in order to avoid a meniscus tear or further meniscus damage.
