May 03, 2020
Meniscus Tear in Knee: Symptoms, Causes, and Treatments
If you have a feeling of instability in your knee, and pain, stiffness and swelling there's a chance you have torn your meniscus. We explain more here.
If you have a feeling of instability in your knee, and pain, stiffness and swelling that doesn’t subside after a couple of weeks of rest, there is a chance you have torn your meniscus.
Meniscus tears in the knee are a very common knee injury – and they can be debilitating and painful, leading to ongoing problems with running, walking and doing any kind of knee bend. They do need to be correctly diagnosed in order to treat them. In most cases, you can recover without surgery, while more serious tears can be effectively treated using minimally invasive surgery.
What is a meniscus tear?
In the middle of your knee joint are two rubbery, C-shaped pads called the menisci. They’re made of a soft cartilage, and are the shock absorbers for the daily impact of simply moving around. They can be torn as a result of an intense twisting or rotating of your knee (they’re also a common side effect of a ligament tear or sprain), or due to arthritis or misalignment in the bones of your knee joint
What causes a meniscus tear?
Meniscus tears can often be a side effect of other injuries – particularly a ligament sprain or tear. Intense twisting or rotating of your knee is likely to tear the meniscus. Meniscus tears can occur as a result of repetitive actions over time – such as kneeling, deep squatting or lifting something heavy.
Who is most at risk of a meniscus tear?
It’s certainly more common to find meniscus tears in people over the age of 40, particularly those who do a lot of sport that involves sudden stops and changes in direction. Athletes who play contact sports, footballers and skiers are particularly at risk. Runners often suffer from torn menisci, but there is no evidence that running itself causes the tear in the first place.
General wear and tear over decades can lead to meniscus becoming thinner and more liable to be torn. Add to that the increasing odds of degenerative bone disease such as arthritis, and you can understand why older people are more susceptible to a meniscal tear.
What are the symptoms of a meniscus tear?
You’re likely to feel:
- Pain when you put pressure through your knee
- Swelling, especially after exercise
- Stiffness – not being able to fully bend or straighten your knee
- Instability – a feeling as though your knee is giving way
- Clicking sensation
Why do you need to get a meniscus tear treated?
If you have these symptoms, it’s important to seek medical advice from an orthopaedic or sports medicine specialist.
There could be underlying problems causing the pain – such as arthritis, bone misalignment or other damage to the structures of your knee.
Without an MRI or ultrasound scan and careful assessment, it is very difficult to work out the causes of your knee pain.
Another reason to get your knee looked at by a specialist is the risk of arthritis in the future. A torn meniscus provides less cushioning, so the end of your thigh bone (femur) and the top of your shin bone (tibia) can rub against each other, wearing away their cartilage coating and leading to early degeneration of the bone surfaces. This can then cause bony growth (bone spurs) to develop, which cause pinching (impingement) and stiffness in your knees.
Treatment of a meniscus tear
The good news is that meniscus tears can be treated effectively, both with and without surgery.
If you have a minor tear in your meniscus, a course of physiotherapy exercises can help to build up the muscles around your knee to compensate for the lack of cushioning.
You may benefit from improving your gait to reduce the impact on your knee joint as you run. Simple exercise modification may also help.
A more serious tear is best treated with surgery, particularly if the torn edges of the meniscus are catching inside the structure of your knee joint.
How is meniscus surgery carried out?
Almost all meniscus repair is done using arthroscopic surgery, which involves using a tiny camera and monitor to see inside your knee. The operation is carried out through small incisions, using extremely fine instruments. This precise, minimally invasive technique helps reduce recovery time.
The most common surgical repairs for meniscal tears are:
- Debridement: jagged edges of the meniscus and loose pieces of cartilage that have been catching inside your knee are trimmed, shaved or vacuumed to enable smooth movement.
- Meniscus repair: the tear is sewn up – meaning the meniscus is still able to provide cushioning in your knee, and reduce the risk of arthritis. The downside of this operation is that cartilage can take a long time to heal (the inner part of the meniscus has virtually no blood supply).
- Meniscectomy: part or all of the meniscus is removed completely. This operation has a quicker recovery time, but there is a risk of arthritis. With effective rehabilitation, as well as ongoing strengthening exercises, this risk can be reduced.
Recovery from meniscus surgery
If you’ve had debridement or a meniscectomy, you can weight bear immediately after the operation and get back to most normal activities within six weeks. By 12 weeks, you should be able to run again. All of this is dependent on following a protocol of physical therapy exercises.
After a meniscus repair, you may have to restrict the weight on your knee for up to six weeks, and wear a knee brace during that period. The brace is designed to stop your knee bending beyond a certain angle while the meniscus heals. With rehabilitation exercises, you may be able to return to sports after another three months.
My advice for anyone with an injured knee
If the pain doesn’t settle down after a couple of weeks of rest, make sure you get it diagnosed.
I have treated so many people over the years who have tried to cope with knee pain by using painkillers and intermittently resting. This often leads to the condition getting worse, and your body compensating for the knee injury, resulting in misalignment of your joints and further problems.
Simon Moyes is an internationally renowned orthopaedic surgeon and leader in the field of arthroscopic (keyhole) surgery. His Capital Orthopaedics team works from The Cromwell Hospital in London, with its state-of-the-art diagnostic and surgical equipment, and top sports medicine professionals.