Meniscus tear

What is a meniscus tear?

A meniscus tear or meniscal rupture describes the tearing of one or both menisci of the knee joint. The meniscus is a cartilaginous, crescent-shaped structure which are located between the femur (thighbone) and tibia (shinbone). 

There is a distinction between the medial (inner) meniscus and lateral (outer) meniscus. Together they facilitate the movement of the knee joint while protecting the joint cartilage.

The medial meniscus is injured more frequently than the lateral meniscus. This is because the medial meniscus is fused to the medial collateral ligament and is therefore less mobile. As a result, the medial meniscus is more susceptible to tears when force is applied to these structures.

The frequency of meniscus tears increases with age, and men are usually affected more often than women.

What causes a meniscus tear?

A meniscus tear can result from various causes. They can be categorized as either degenerative and traumatic in origin.

• Degeneration:

Due to ageing-related wear and tear, the meniscus becomes less resilient and elastic with age. Therefore, the menisci can no longer withstand repeated stress, resulting in multiple small tears, referred to as microtears.

Particularly those in professions that involve heavy knee strain are commonly affected by degenerative meniscus tears. These include tilers, miners, or football players.

• Traumatic:

A classic injury mechanism leading to meniscal tears involves rotational movements of the knee under load. These so-called twisting-fall injuries are typical for football or skiing accidents.

A common skiing injury is the unhappy triad. It is characterized by a combination of a rupture of the medial meniscus, the medial collateral ligament, and the anterior cruciate ligament (ACL). Such injuries are usually caused by a strong rotational force acting on the loaded knee.

However, in many cases it is difficult to determine the exact origin of the meniscus tear, whether it has a degenerative or traumatic origin. It is often a combination of both. The more degenerated a meniscus is, the more easily it tears during trauma.

Symptoms of a meniscus tear

Depending on how quickly a meniscus tear develops, it can cause mild to severe symptoms. Meniscus tears caused by slow degenerative processes can even remain asymptomatic. 

Ruptured menisci usually lead to impaired flexion and extension of the knee. They are often accompanied by pain in the back of the knee and on the side of the affected meniscus during physical activity. The pain may even radiate down to the shin. Many patients particularly notice discomfort when squatting or rising from a squatting position.

Another possible symptom is a joint lock that can be caused by a freely moving fragment of the ruptured meniscus. This occurs when a fragment of one or both menisci becomes entrapped in the joint space, leading to acute pain or significant restriction of movement.

Possible accompanying symptoms of an acute, trauma-related meniscus tear are swelling and redness of the entire knee. However, degenerative meniscus tears may also temporarily cause similar symptoms. In these cases, this is due to an inflammatory response to the overuse of the joint.

How is meniscal damage diagnosed?

The most important diagnostic tool for detecting meniscal damage is the physical examination of the knee. It should be preceded by a thorough medical history.

During the physical examination, targeted pressure is applied to the medial and lateral meniscus to assess and localize possible pain. Moreover, the range of motion of the knee and tenderness along the joint space are assessed.

If a meniscal tear is suspected due to suggestive clinical signs during the examination, further imaging studies are ordered. In some cases, an x-ray is performed. Even though the menisci cannot be shown on an x-ray, the image can be suggestive of degenerative changes of the knee. 

The gold standard for diagnosing meniscal tears is magnetic resonance imaging (MRI). This imaging method is well-suited for visualizing soft tissues. Not only can it detect meniscus tears, but also potential damage to the articular cartilage.

A knee arthroscopy (joint endoscopy) can be performed to precisely assess the extent of the meniscal damage. Optionally, a part of the meniscus can be removed and analyzed in the laboratory, providing further insights into the underlying cause of the meniscal tear.

As the arthroscopy is considered an invasive procedure, it is more commonly used for the treatment of a meniscus tear, rather than for diagnostic purposes only.

How is a meniscus tear treated? 

The appropriate treatment for a meniscus tear depends not only on the diagnostic findings but also on the severity of the patient’s symptoms and overall health.

Generally, a distinction can be made between conservative and surgical treatments.

• Conservative treatment: Smaller tears in a well-vascularized lateral meniscus usually do not require surgical treatment. Instead, the therapy involves a combination of pain medication, icing, rest, and physiotherapy. This way, small tears can heal on their own. Regular follow-up examinations are crucial to monitor treatment success. If the symptoms persist despite conservative treatment, surgery should be considered.
• Surgical treatment: The goal of meniscus surgery is always to preserve as much functional meniscal tissue as possible and to restore the mobility of the knee. Depending on the extent of the meniscal damage, a minimally invasive procedure may be performed, involving either suturing of the meniscus or the removal of torn meniscus fragments. Tears of well-vascularized menisci can often be sutured successfully, whereas poorly vascularized areas heal less successfully. These parts are removed to prevent them from irritating and damaging the articular cartilage.

An open surgical procedure is very rarely performed. This is typically reserved for complex cases that involve additional injuries to nearby ligaments or articular cartilage.

When is surgery necessary?

If conservative treatment is insufficient, surgical treatment may be necessary. Generally, surgery is indicated for larger, complex tears in poorly vascularized medial menisci, as well as loose torn fragments in the joint space.

How is a meniscus surgery performed?

In most cases, the surgery is performed on an outpatient basis using knee arthroscopy. Therefore, most patients can go home after a short observation period.

The procedure is typically performed under short general anesthesia, or alternatively under regional anesthesia of the lower extremity. The choice of anesthesia is made by the anesthesiologist and depends on the patient’s general health status and preferences.

An arthroscopy only requires small skin incisions to introduce various surgical instruments. These include a small camera with a light source (arthroscope), allowing the surgeon to thoroughly examine the inside of the knee. If the surgeon decides to suture the meniscus or remove some fragments, additional tools such as graspers, scissors, or suturing devices are introduced into the knee joint.

The procedure takes less than 90 minutes on average. After the patient wakes up from anesthesia, they will be monitored for a short time. Finally, the patient can be discharged using crutches. In the very rare case of any postoperative complications, it is advisable to have an adult nearby for the first night after surgery. 

The first dressing change takes place on the following day. Usually, only small adhesive plasters are needed to cover the small skin incisions. To prevent excessive swelling, compression stockings are recommended for the first days.

The sutures should be removed after about 10 days, after which the patient may resume showering or bathing without further precautions.  Depending on the extent and type of procedure, crutches are usually used for 3 to 4 weeks, after which their use can be gradually reduced.

The aftercare includes a physiotherapeutic program during which weightbearing is gradually increased. Moreover, lymphatic drainage is often performed during the early postoperative weeks to promote the resolution of swelling. 

How long does recovery from a meniscus tear take?

The healing time for a meniscus tear varies from person to person. The key factors that influence recovery are the size of the tear and the extent of the damage. With conservative treatment, healing usually takes several weeks to several months.

In the case of surgical treatment, full weight-bearing can be expected at around 6 weeks. However, the return to sports should not be attempted before 3 months postoperatively.

Which physicians and clinics are specialists in the diagnosis and treatment?

The knee is a major joint in the body that is constantly exposed to mechanical stress. To minimize the consequences of knee injuries, it is recommended that any complaints be evaluated and treated only by experienced specialists.

Specialists in the diagnosis and treatment of a meniscus tear are are board-certified physicians in orthopedics and surgery with the subspecialities in knee surgery, sports medicine and trauma surgery. These specialists often work in specialized orthopedic clinics or practices. 

We help you with finding an expert for your condition. All listed physicians and clinics have been verified and selected based on their outstanding expertise in the field of meniscus tears. They look forward to responding to your inquiry or treatment request.