Torn meniscus in knee: what should you do?

A torn meniscus in knee is a common cause of knee pain affecting active sportspeople and the elderly. Previously, we would treat a torn meniscus with keyhole surgery. However, recent evidence suggests that most torn meniscus settles with physical therapy. So, how should you treat a torn meniscus?

What is the meniscus?

The meniscus is c-shaped cartilage that sits in the knee joint. There are two menisci – one on the inside (medial meniscus) and one on the outside (lateral meniscus). The primary function of the meniscus is to act as a shock absorber and provide stability. So a tear can lead to pain and a feeling of locking or giving way.

Causes of a torn meniscus in knee

Some cases of cartilage tear arise from an acute injury. For example, a sudden twist during sports such as football, skiing, or rugby can lead to a meniscal tear. However, some cases have no history of acute injury. As we age, the meniscus becomes weaker and prone to injury.

How do you know if meniscus is torn?

Overall, the diagnosis of a meniscal tear requires a clinical assessment and imaging.

Generally, symptoms related to a meniscal tear include:

• pain on the inside (medial meniscal tear) or outside (lateral meniscal tear) of the knee. Sometimes, pain can move to the back of the knee.

• swelling located below and above the kneecap,

• a feeling of instability also called giving way

• catching or clicking sensation of the knee,

• an inability to fully bend or straighten your knee

• a lump on the inside or outside of the knee secondary to a meniscal cyst. Generally, cysts form from a meniscal tear.

Your doctor will examine your knee to confirm a diagnosis and rule out other knee injuries. Examples of other injuries include anterior cruciate ligament injury or medial collateral ligament injury. Again, an expert in knee injuries can rule out these conditions.

Often, imaging is needed in the assessment of a meniscal tear. A standing X-ray is vital to see if you have arthritis in the knee. Generally, an MRI scan is also used to diagnose a meniscal tear.

Meniscus or cartilage tear: what is the difference? 

Often, there is confusion between a meniscus tear and a cartilage tear. People often use them interchangeably, causing some confusion.

The knee joint contains two types of cartilage. One type is called articular cartilage, forming a smooth surface covering the bone ends. On the other hand, the menisci are a different type of cartilage that sits between the bones and acts as a shock absorber.

Articular cartilage injuries are often described as thinning, a flap, or a defect. Injuries to the cartilage can produce symptoms similar to a meniscal tear.

Treatment of a torn meniscus in knee

Overall, we treat most meniscal tears with conservative therapy. Generally, this rule applies to degenerative tears, tears that occur without trauma, such as an acute knee twist.

Usually, initial treatment consists of ice (ice pack 10-15 mins every 2-3 hours), knee joint compression (using a compressive bandage), and anti-inflammatory tablets such as ibuprofen.

Next, we refer you to a physiotherapist to return you to sport or full function. In general, physical therapy should improve range of motion, strength, and balance of the knee. Treatment should also focus on building strength and control in the hip and pelvis.

Some doctors try a cortisone injection into the knee if you get stuck. We perform injections into the knee joint or directly surrounding the meniscal tear. Recently, some doctors have been using platelet-rich plasma or PRP injections into the cartilage tear to help with cartilage healing.

But don’t all meniscal tears need surgery?

Actually no. If we perform MRI scans on people with no knee pain, a significant number will have a meniscal tear. And a surgeon would not recommend surgery in these cases. So, the presence of a tear on the scan should not be the reason to have surgery.

In general, evidence would support physiotherapy. For example, in a recent study, people with a partial meniscal tear had surgery or physiotherapy. There was no difference between groups either in knee pain or function at three months and two years. Also, there is some evidence that having keyhole surgery increases your chance of having a knee replacement by 30%.

Moreover, a recent review collecting all high-level evidence for meniscal surgery suggests that key-hole surgery provides a small benefit compared to physiotherapy. However, the benefit only occurs in those people with no underlying arthritis. Generally, you should avoid surgery if you have co-existing knee arthritis. Removing part of the meniscus in knee arthritis may accelerate the wear and tear and lead to earlier knee replacement.

So best to stay away from keyhole surgery if you can.

However, some cases need surgery. Some of these cases include:

• Persistent pain that does not settle within 24 weeks of exercise therapy

• Gross swelling of the knee limiting the range of motion

• Mechanical symptoms such as the feeling of instability, giving way, or locking

• Traumatic tears occur with an acute knee twist, especially in younger people. In particular, traumatic lateral meniscal tears need closer attention. Overall, we think that vertical or horizontal tears near the edge of the joint have better healing potential with sutures.

• Meniscal root tear: this meniscal injury requires urgent surgical review to prevent further damage to the meniscus and articular cartilage. See the illustration below.

Athletes with a torn meniscus: Do we treat it differently?

Generally, we believe that young athletes with a torn meniscus need surgery early. However, new findings question this thinking. Young athletes with a meniscal tear were randomised into immediate surgery or physiotherapy. After 12 months, there was no difference between groups for pain or return to sport. Also, only one in four athletes who had physiotherapy eventually required surgery. So, even for young athletes, we should consider a trial of physiotherapy in almost all cases.

Treatment for cartilage loss in knee

Generally, a cartilage injury such as a fissure, flap, or defect is treated conservatively, similar to early arthritis.

Usually, we only consider surgery in young people who have a single defect traditionally related to trauma. Options include microfracture or autologous chondrocyte implantation. Overall, these options are only used in small numbers of people and require a long recovery.

Other common questions related to a torn meniscus in knee:

Can a meniscal tear heal on its own? 

When a meniscus tears, bleeding and inflammation ensue. Sometimes, the meniscal tear can scar up and heal. Generally, healing potential is better on the periphery of the meniscus, where the blood supply is better.

Can I walk with a torn meniscus? 

It depends on the severity of the symptoms. But yes, most people with meniscal tears can walk for fitness.

Final word for Sportdoctorlondon on a torn meniscus in knee

Meniscal tears are a common cause of knee pain. Generally, we recommend a trial of therapy followed by injection if needed for degenerative tears. Often, we perform injections into the knee joint and around the meniscal tear. Finally, surgery is only for traumatic tears or when conservative management fails.

Other related conditions: 

• Meniscal injections
• Meniscal cyst
• Baker’s cyst