The menisci are crescent-shaped pads of cartilage within the knee joint, positioned between the thigh bone and the shin bone. You have one meniscus on each side of your knee – the medial on the inside and the lateral on the outside. They act as shock absorbers cushioning the joint as you walk or run and protecting the bones from wear and tear.
A meniscal tear is a common injury, particularly among people who play sports or in older people. It can be painful and debilitating and is one of the most frequently occurring cartilage injuries of the knee that we see here in the clinic.
What causes a meniscal tear?
Sports-related tears are generally the result of twisting your knee and are most common in sports such as football or basketball. As you get older you are more likely to develop a degenerative tear which can be caused by even quite minor injuries such as standing up awkwardly from a sitting position.
Who is at risk?
You are particularly at risk of meniscal tears if you compete in contact sports like football, as well as sports that involve jumping and quick changes of direction like volleyball and basketball. Ageing is also a factor as the meniscus weakens with age and around 40% of people over the age of 65 develop meniscal tears. Older people who play sport may be at particular risk of injury.
What are the symptoms?
Many people feel a characteristic ‘popping’ sensation when they tear their meniscus. You may not immediately feel pain and you may still be able to walk on your injured knee, however it may gradually stiffen and the pain may intensify. Some people with a torn meniscus feel only intermittent pain and in some cases the pain is fairly mild. Other signs that you may have a meniscal tear include swelling around the injury site, which tends to develop within a few hours, and a feeling of instability in your knee. When the knee is bent you may hear it clicking or it may catch. It may be difficult to fully bend and straighten your knee.
When your meniscus tears, sometimes a piece of cartilage breaks loose and it can become caught in the knee joint, causing it to lock. It is quite common for meniscal tears to be accompanied by other knee injuries, such as damage to the anterior cruciate ligament.
How is it diagnosed?
Diagnosing a torn meniscus involves a physical examination and you may need an X-ray to rule out a fracture. Sometimes an MRI scan is used to determine the extent of the damage to the knee cartilage.
What to do if you tear your meniscus
Not all meniscal tears require surgery and some injuries heal by themselves. You can support your own recovery by following the RICE method (rest the knee, use an ice pack to reduce pain and swelling, compress the knee using an elastic bandage or neoprene sleeve and elevate it with a pillow under your heel while sitting or lying down). Taking anti-inflammatories and doing exercises to stretch and strengthen the knee may also help.
The position of the meniscal tear is a key factor in determining whether or not you will need surgery. The outer section of the meniscus has a good blood supply and may heal on its own whereas the inner two thirds does not have a good blood supply and so require surgical repair if they becomes torn. We will cover surgical treatment for meniscal tears more fully in a future blog.
Preventing meniscal tears
While accidents may be unavoidable, there are some things you can do to reduce your risk of meniscal injuries. These include warming up thoroughly before sport, doing regular exercises to maintain the flexibility and strength of your thigh muscles, wearing the correct shoes for sport and building up your fitness levels slowly. Avoid increasing the intensity of your workouts too quickly and never push yourself if you are tired as fatigued muscles are more prone to injury.
Contact us for advice about diagnosing and treating suspected meniscal tears.