The meniscus is a type of cartilage in the knee which acts as a shock absorber as well help in stabilising the knee joint.
Meniscal tears are among the most common knee injuries. Athletes, particularly those who play contact sports, are at risk for meniscal tears. However, anyone at any age can tear a meniscus. When people talk about torn cartilage in the knee, they are usually referring to a torn meniscus. Once damaged the meniscus don’t heal as they have very poor blood supply.
The most common symptoms of the meniscal tear are:
- Swelling of the knee
- Catching or locking of the knee
- Clicking sensation
- Sensation of knee ‘giving’ way
- Sometimes the torn bit of the meniscus can become loose and may float in the knee joint. This may cause acute locking.
Because other knee problems cause similar symptoms, your doctor may order imaging tests to help confirm the diagnosis.
X-rays. Although X-rays do not show meniscal tears, they may show other causes of knee pain, such as osteoarthritis.
Magnetic resonance imaging (MRI). This study can create better images of the soft tissues of your knee joint.
The treatment of the meniscal tear depends on the symptoms and the MRI findings. If the tear is in the outer third of the meniscus and the MRI scan does not show any healing then it may require arthroscopic repair. The repair tend to heal better if performed early.
In contrast the inner two thirds of the menisci do not heal and have to be resected/trimmed/removed by arthroscopic (key-hole) surgery. Knee arthroscopy (pdf document link) is one of the most commonly performed surgical procedures. In this procedure a fibre-optic telescope (arthroscope) is inserted in the joint through small stab incisions (<1 cm). This helps in direct visualisation of the knee and at the same time most conditions can be treated.
Most arthroscopic surgery is undertaken as a day-case procedure and is usually performed under general anaesthesia. Patients are admitted on the day of surgery.
Many patients can return to work within a week if in a desk job or within two weeks if in a manual job or on their feet a lot. Depending on what is done within the knee, light training can be started at around 2 weeks following surgery and full sports at around 6-12 weeks.
Meniscal tears are extremely common knee injuries. With proper diagnosis, treatment, and rehabilitation, patients often return to their pre-injury abilities.
In very few cases where there is a large tear and the whole meniscus needs to be removed there is a role for meniscal transplant.