• www.sportordination.at
  • www.sportordination.at
  • www.sportordination.at
  • www.sportordination.at
  • www.sportordination.at

Meniscus

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Image 1: View of the lateral meniscus (LM) and medial meniscus (MM) from above.

The medial and lateral menisci carry out the shock absorbing function in the knee joint. They are crescent or sickle-shaped structures that lie between the thigh and lower leg. The meniscus (similarly to the intervertebral discs in the spine) consists of fibrous cartilage, a rubber-like substance, and, in addition to its shock absorbing function, is tasked with guiding movements of the knee joint and stabilising the joint in addition to the ligament structures.

Image 2: There are also various types of tear (such as horseshoe tears, radial tears, bucket handle tears etc.)

Even with menisci, acute injuries (often this involves sporting injuries such as those sustained during skiing, football etc., however a meniscus injury can also be caused by significant turning when standing up from crouching), can be differentiated from degenerative, i.e. "wear-related" damage. Injuries of the medial meniscus are significantly more common than injuries of the lateral meniscus, as the medial meniscus grows firmly together with the collateral ligament.

Image 3: Meniscus tear
Image 4: The meniscus is only well perfused in its area of attachment to the joint capsule (zone I or red zone) and is also able to heal well in this area.
Image 5: The large image shows a damaged frayed meniscus, the small image on the top right shows the condition following removal of the damaged meniscus section and meniscus smoothing.

In the event that meniscus damage is determined, an operation (arthroscopy of the knee) is favoured very early on, even if there is no or very little pain, because a damaged meniscus causes constant wear on the cartilage. As a result, this can very quickly result in cartilage damage.

This irritation also rarely stops as the meniscus is barely perfused and can rarely heal itself.

There is only a good tendency for healing in the red zone (image 4). Perfusion and therefore the tendency to heal decreases constantly in a medial direction until zone III.

These constant wear movements on the damaged meniscus in untreated meniscus injuries lead to recurring pain on exertion, signs of impingement, swelling of the knee joint and secondary damage to the cartilage surfaces and therefore to early-onset arthrosis.

Cysts occasionally form on the base of the meniscus, this is called a ganglion (or meniscus ganglion). A ganglion is usually filled with a jelly-like fluid. In the majority of cases, a meniscus tear also exists, which must be treated immediately. Removal of the ganglion alone, without rectifying the cause, usually has no merit.

During arthroscopy of the knee joint, only the damaged section of the meniscus is removed and the meniscus is carefully smoothed.

Retention of the meniscus can be attempted in order to minimise the risk of arthrosis that exists following partial removal of the meniscus. Suturing of the meniscus is only carried out in rare cases, primarily in zone I (see image 4).

The advantage of meniscus refixation is that the increased risk of arthrosis, which exists following partial removal of a meniscus, can be minimised. The disadvantage of meniscus refixation is that patients are not permitted to bear weight on the leg that has been operated on for up to six weeks - and even then, there is still a relatively high risk of a repeat tear. The conditions for healing are only ideal if meniscus refixation was possible in zone I (see image 4).

FOLLOW-UP TREATMENT:

 

Following a meniscus operation (partial removal of the damaged meniscus), weight bearing on the leg is possible immediately, provided that the patient's pain permits this. Crutches are often only required for a few days. Bicycle riding or ergometer training is possible after two weeks, running after four weeks, and ball sports and skiing after six weeks.
Following suturing of the meniscus and meniscus refixation, mobilisation on crutches with no weight bearing is required for four weeks, followed by two weeks in which weight bearing is permitted with half the patient's body weight. Immobilisation using a splint is often not indicated, with the exception of the presence of existing concomitant injuries, e.g. of the collateral ligament. Bicycle riding or ergometer training is possible after six weeks, running after twelve weeks, and ball sports and skiing after six weeks.

No restrictions are to be expected after a meniscus operation in terms of sport. Returning to the different types of sport depends on the operation method and the extent of the damaged meniscus tissue. It must be made clear, however, that there is a direct correlation between the extent of the resected meniscus tissue and the statistical likelihood of early-onset arthrosis. The more meniscus tissue that has to be removed, the more likely it is that the patient will suffer from early-onset joint wear (arthrosis).

 

Please note that medical indications and treatments change constantly. Sometimes these changes occur more rapidly than I am able to update on my homepage. Some information regarding dosage, prescription and compositions of medications may have changed in the meantime. Reading an internet page cannot replace visiting a doctor - it may be that during an examination and subsequent discussion with your doctor, other information is also communicated as a result of new scientific knowledge.