Meniscus Deficiency
Meniscal Transplantation
Phone +971-2-4446600
Anatomy
There are two menisci in the knee, one medial (inside) and one lateral (outside).
The menisci act as cushioning and stabilizers of the knee. The cushioning is generally the effect most associated with meniscus and plays an important role in decreasing the load on the cartilage in the knee. It is when the cartilage loading forces are too large you can get injuries and eventually osteoarthritis of the knee.
In the past, the techniques to repair injured menisci were less effective and not as commonly used. Instead, a lot of these tears were treated with resection of parts or the entire meniscus. Sometimes this is still needed today, but as often as we can, we try to preserve the meniscus as we now know that being left without proper cushioning can lead to pain, swelling and osteoarthritis in the knee. This is due to overload of the cartilage and has previously been very hard to treat in any good fashion, but over the last decades better and better techniques have become available and we are now at a stage where we have the ability to replace the lost meniscus with a donor meniscus, called meniscus transplant.
Evaluation
As with other injuries, a thorough history and examination is a great start. The most common complaint of meniscus deficiency is loading pain from one side of the knee and recurrent effusion during or after activities. If the patient has had previous meniscus resection and examination shows signs of a deficiency, further evaluation with x-rays and MRI are needed. X-rays can evaluate any grade of osteoarthritis and alignment, as these are factors that can play a large role in the treatment options.
MRI will help to diagnose the loss of meniscus tissue and can show signs of overload or reduction of the cartilage.
As a secondary function, a meniscus also contributes to stability of the knee. As an example, the posterior horn of the medial meniscus supports the ACL and lessen the load on the ligament. In a knee with a previous ACL reconstruction and medial meniscus resection, the function of the ACL can be worse and actually lead to failure of the ligament.
Treatment
For most patients with previous meniscus resection and ongoing pain, physiotherapy and sometimes anti-inflammatory medicine or injections will help the patient very well, and no other treatment is needed.
However, in younger individuals with a long active life ahead of them with ongoing pain and swelling reducing their possibility to stay active and healthy, it might not be enough.
That is when a meniscal transplantation surgery can be performed. That is, a donor meniscus replacing the previously resected meniscus to increase cushioning in that specific part of the knee and lessen the load on the cartilage. This is an uncommon procedure, usually done to improve a bad knee, rather than to get that knee back to sports. It doesn´t work as well in overweight patients or when the osteoarthritis has developed too far and therefor has a quite narrow indication.
In the setting of an unstable knee, partly due to meniscus deficiency, if a surgery is needed to reconstruct the ligament, a meniscal transplant could not only protect the cartilage, but also potentially improve the stability of the knee and longevity of the ACL reconstruction and is therefore the second possible indication for such a surgery.
The procedure is done by first preparing the meniscus with bone blocks and sutures and thereafter prepare the knee with an arthroscopic cleaning of the remainder of the previous meniscus. Thereafter, bone sockets are made to put the graft in the right anatomical position and the meniscus is introduced in the knee, anchored in the sockets and sutured to the capsule.
Rehabilitation
After a meniscus transplant the donor meniscus needs time to heal and during the first 6-8 weeks, no weightbearing is allowed and thereafter focus is on getting back to a normal walking pattern which usually takes up to three months in total.
Physiotherapy initially plays a major role on a daily basis, and once you’re able to walk further strength training and mobility training is needed. The total rehabilitation time is a year and as previously mentioned the expected result is to live an active life with minimal pain and instability, but going back to sports is for most transplants not tolerated very well.