What is the meniscus?
The meniscus forms two crescents composed of cartilage. In the knee, there is an inner and outer meniscus. The meniscus has several functions. The main functions of the meniscus are:
- Steering of the knee especially during bending and stretching
- Agility, suppleness
- Protective effect; protect cartilage
- Caring function
- Stabilizing function
- Pressure distribution in the knee
When a meniscus injury occurs, one or more of these functions may be affected.
What happens during meniscus injury (genesis)
Degenerative injury of the meniscus
In some cases, this can also occur as a result of an aging process. This is called degeneration. Just as we get gray hair or wrinkles, our body is also subject to aging from the inside. This aging is a normal process that occurs biologically in each individual person from a certain age. The quality of the tissue, including the meniscus, decreases. This increases the risk of injury. The complaints often arise gradually and increase over time. Because the quality of the meniscus decreases at a later age, the risk of an acute injury may also increase, especially when fanatical sport is still practised or physically demanding work is involved.
Symptoms of meniscus injury
Meniscus injuries often cause the knee to move less smoothly. Because the meniscus is located in the capsule of the joint, there may be fluid in the knee. We call this hydrops in the medical world. Bending the knee often causes symptoms. We also see that activities such as climbing stairs or deep squatting provoke the symptoms.
Other symptoms that may occur with meniscus injury include:
- Pain in knee; nagging/stabbing/burning
- Instability complaints
- Clear pain localization (clearly identifiable), at the level of articular cleft of knee.
- Unstable feeling or uncertainty in movement
- Decrease in muscle mass, we then speak of muscle atrophy. Especially in the quadriceps
Does surgery make sense?
Research has shown that physical therapy is just as effective as operating on a meniscus tear. Thus, physical therapy is a good first choice to improve meniscus symptoms. Physical therapy has an edge in this sense precisely because we see that in those individuals who have undergone surgery of the meniscus develop wear and tear in the knee more quickly. This will have to be investigated further. Because of this development we see that meniscus complaints are often first treated conservatively. This means without surgery. The only exception is in case of structural lock complaints. It may be that a severe tear in the meniscus locks the knee. It is therefore impossible to move. The meniscus is then caught between the two parts of the bone and is stuck. This must be treated surgically. The stuck part of the meniscus is removed or stitched back into place. The chance of natural recovery also depends in part on where the tear is located in the meniscus. We distinguish between three different zones. The outer zone is called the red zone. This part of the meniscus is well supplied with blood. For this reason, the chance of recovery is greatest here. The middle zone is the red-white zone. Here, there is a blood supply but much less than in the outer zone. The inner zone we call the white zone, where the blood supply is the least and therefore the chance of recovery is also minimal. The better a structure is supplied with blood, the better nutrients can be transported to it. With these nutrients, new cells can repair the damaged tissue. The eventual recovery of the meniscus therefore also depends on the location of the injury.
Conservative treatment of a meniscus tear is always preferred initially. Natural recovery often occurs within a few weeks to months. An average rehabilitation of a meniscus tear takes 12-16 weeks. During this time, there should be a noticeable reduction in symptoms. During this treatment, the focus is on muscle function, gait and mobility of the knee. If there is no structural improvement after this period, further examination of the knee is necessary. By means of keyhole surgery or MRI a statement can be made about the extent of the injury. Suturing of the meniscus is preferred in order to preserve as much function as possible. If this is not possible, the damaged part of the meniscus can be cut away. Physiotherapy is also recommended after surgery to aid recovery.