The common signs of meniscus tear
Written in association with:A meniscus tear is a common and painful injury, which can occur if you suddenly twist your knee. It tends to happen when playing sports such as tennis, rugby or football, or if you work in a job the requires heavy lifting or as the result of age-related wear and tear. We asked one of our expert orthopaedic surgeons, Mr Rohit Jain, to explain the specific symptoms and signs of a meniscus tear and just how easy it can happen.
What is the structure and function of the menisci?
The menisci are C-shaped structures which are made up of fibrocartilage and are present in between the thigh bone and the leg bone. They are C-shaped and in cross-section appear wedge-shaped. They are tough and rubbery in texture.
The menisci act as shock absorbers and have several functions, but the most important one is that they help in load transmission and distribute the forces going through the joint in an equal fashion across the surface. This happens so that there are not any pressure points in the joint. The menisci also make the joint more conforming and add to the stability of the knee joint.
How easily can a meniscal tear?
The classical mechanism that causes a meniscal tear is loading and twisting. Any form of pivoting sports is prone to these tears, which includes racquet sports, such as tennis and badminton; football, rugby and skiing.
You don’t have to be an athlete to cause a tear in the menisci. Sometimes standing up quickly from a squat position can also sustain a tear. People who work in occupations that involve a lot of lifting of heavy loads and twisting are at risk of a tear. It also depends upon the quality of your menisci.
As we grow older, meniscal tissue starts to degenerate and is more prone to any kind of force, which can tear it and make it vulnerable. Younger individuals need a fair bit of force, but in old age, a little force can lead to a meniscus injury. These injuries are extremely common and widespread in all age groups.
Are there different types of a meniscus tear?
The two basic methods of classification are based on the location and the pattern of the tear. The meniscus is classified into two zones, the red and the white zone. Only a small peripheral part of the meniscus has a blood supply. The remaining part, which lays on the surface of the joint, has no blood supply of its own and gets it nutrition from the joint fluid. The location of the tear is based in reference to the blood supply.
The red zone is more vascular, which means that it has a sufficient blood supply. There is the red-white zone, which is partially vascular, and the remaining part with no blood supply is the white zone. The tear can be through any of these zones.
The pattern of the tear can be horizontal or vertical and it becomes complex if it has both of these elements. If a tear is in a red zone, the chances of it healing are higher because it has its own blood supply.
The majority of meniscus tears are in the white zone and the healing potential is pretty low and therefore most of those tears require surgery, especially if they are causing mechanical symptoms in the knee joint. These locations and patterns determine how we treat the tear.
What are the symptoms of a torn meniscus?
When making a diagnosis of a torn meniscus, we look at both the symptoms and the signs of a tear. The symptoms are what the patients feel, and the signs are what we as surgeons would pick up on during examination.
The most common symptom is pain, which will either be on the inner or the outer side of the joint. It is typically associated with swelling that tends to come a little bit later and may not be apparent straightaway.
The mechanical symptoms of a meniscus tear include clicking, intermittent jamming/locking of the joint, and the feeling of a ‘giving way’ sensation. The pain is usually dull but sharp and stabbing, which is exacerbated suddenly with a twisting movement.
The specialist will go through the signs of a meniscus tear by taking a thorough medical history of the patient and by making a physical examination to tie things up together. A clinical diagnosis will be confirmed through the use of imaging using an X-ray and an MRI scan.
If you would like to book an appointment with Mr Jain for his expert opinion on your knee pain, you can do so via his Top Doctor’s profile here.