Meniscus Replacement Reviewed At AAOS. Can Knee Replacement Be Deferred?

Qmed has reported on a discussion which took place at the American Academy of Orthopedic Surgeons(AAOS) meeting last week on the subject of meniscal transplantation, a subject close to the heart of practitioners of total joint surgery, sports med surgery and arthroscopists.

According to the report, at the AAOS congress a group of renowned orthopedic surgeons from around the world gathered to discuss the latest findings on meniscus transplantation. New data on knee joint cartilage and meniscus transplantation presented at the 27th annual Meniscus Transplantation Study Group revealed that the meniscus tissue can be successfully replaced by tissue replacements such as cadaveric allografts, using artificial materials such as polyurethane scaffolds, and using polycarbonate-urethane implants. These advances bode well for all those who have developed knee pain or arthritis and want to avoid a total knee replacement.

Background

The meniscus cartilage is often described as the key “shock absorber” in the knee joint, providing a combination of protection and stibility to what is an extremely heavily loaded joint. When damaged, whether through injury or degenration, it is often partially removed. In years gone by sports practitioners referred to “having their cartilage out”, which meant all of at least one troublesome meniscus. It was tantamount to having a tooth out back in the seventies, yet the consequences of removing this key structure are usually an earlier onset of arthritic changes and pain associated with bone-on-bone contact, often ending with a knee replacement.

In recent times new instruments and better arthroscopic technique, coupled with a myriad of devices designed to repair meniscal tears has meant meniscal injury often need not mean the end of an active life or an inevitable progression to arthritis and knee replacement surgery. However, significant meniscus can still be “lost” in cases where it cannot be repaired (as it has little or no blood supply on its inner two thirds), and a lack of this critical structure often leads to joint pain and arthritis. In such cases one option is the meniscal transplant, a complex procedure and one not yet considered mainstream. Consequently it’s interesting to note that an esteemed group is talking about it at AAOS.

The AAOS sessionĀ 

According to Qmed, “Eight investigators from five different countries presented on the science of meniscus replacement.”

Key speakers were as follows:

Kevin R. Stone, MD of the Meniscus Transplant Center at The Stone Clinic in San Francisco presented the largest and longest study of meniscus transplantation using donated tissue. The study spanned 16 years of data with approximately 80% success at improving patient pain and function in both pristine and arthritic knees. Many patients were able to return to a wide range of sporting activities after undergoing meniscus transplantation.

Mathew T. Provencher, MD, MC, USN of the US Navy presented data on the biomechanical changes in the knee for soldiers with a new meniscus and an osteotomy realignment procedure. The soldiers’ pain was diminished and some were able to return to active duty.

Peter Verdonk, MD of Belgium unveiled a novel artificial meniscus implant made from polycarbonate-urethane. The concept here is that the synthetic implant encourages cellular ingrowth resulting in meniscus-like tissue. The implant is meant for patients who have a missing meniscus and knee pain, but whose knees are otherwise healthy. The data is preliminary but represents a new bionic approach to cartilage replacement.

We say

What’s clear is that there is no “insert and leave” meniscus implant. In all cases it seems that we’re unlikely to see a return to pre-injury levels of meniscal performance or particularly impressive longevity. Dr Stone’s own clinic suggests a 9 year survival for donated meniscus. But as a way of deferring an inevitable knee replacement or giving the patient a higher degree of mobility and lower degree of pain, there is no doubt that the technology of the meniscal transplant is likely to continue to evolve. As a 49 year-old frequent golfer with a dodgy knee and constant fear of having to prematurely resort to Sky for my golf fixes (not yet you understand) I’d be in the queue.

Source: Qmed, medlatest staff