Bio Dynamic Technologies


The Osteoarthritis-Meniscus Connection

Ahhh, youth…we feel as if we could spread our wings forever…we are invincible! And yet, sometimes, our bodies teach us otherwise. Joints may become stiff or achy due to lack of use. If you have osteoarthritis (OA) in the knee, you might be familiar with the condition’s various symptoms, including sudden weakness or pain. And there could be increased pain if you experience a potentially serious cartilage injury – such as a tear in the meniscus, the cartilage in the knee that cushions and stabilizes the area between the shinbone and the thighbone.

Interestingly enough, a torn meniscus may also accelerate the loss of cartilage in people who already have OA. So knowing whether or not you have had a meniscus injury can be an important factor when considering how to relieve OA knee pain.

Many things can cause a meniscal tear – whether you were playing a rigorous tennis game, or simply getting up from the couch. If you do experience a meniscal tear, you have a lot of company. In fact, meniscal tears are the most frequently experienced and treated injuries in the knee joint. According to recent research, more than 500,000 meniscal tears take place in the United States each year. And meniscal injuries tend to occur in two particular groups of people: young people who are injured during sports, and older people, who also happen to be at the greatest risk of developing OA.

How the Meniscus Works

The meniscus is a piece of cartilage sometimes described as “wedge” or half-moon shaped.  Located between the weight bearing joint surfaces of the thighbone (femur) and the shinbone (tibia), it is typically attached to the lining on the edge of the knee joint.

Each knee has two menisci: the lateral meniscus located on the outside, and the medial meniscus on the inside of the leg. The meniscus acts as a shock absorber when walking and helps to bear weight by distributing stress evenly down the knee. According to WebMD, each meniscus helps to “evenly load the surface during weight-bearing and also aids in disbursing joint fluid for joint lubrication.”

Anyone can be prone to a meniscus injury, whether it is a teenage soccer player who’s lunging after the ball, a 40-something who suddenly twists to make that seemingly impossible basketball shot just outside the key, or a 60-year-old who does a too-deep knee bend in Taekwondo. Athletes of any age can be at risk for meniscal tear, although some athletes, including soccer players as identified in this study, are at greater risk the older they get.

Symptoms of Meniscus Injuries

People with a torn meniscus may experience:

  • Pain (exacerbated when twisting or rotating the joint)
  • A popping sensation that accompanies certain movements
  • Swelling and stiffness in the knee joint
  • Difficulty with knee motion and mobility
  • Difficulty fully extending the knee and straightening their leg

Meniscus Injuries May Predict Future OA

Just as a head cold can leave your immune system vulnerable to other problems, a meniscal tear can render your knee vulnerable to developing osteoarthritis (OA) in the future. Having a torn meniscus affects the weight-bearing ability of the knee, so the other ligaments and tendons must compensate, which can add more stress to the knee. In addition, while the shin and thigh bones typically move smoothly against one another, a tear in the meniscus interferes with this, causing the ends of both bones to come into contact and rub against one another. Both of these conditions have been found to contribute to the development of osteoarthritis.

Experts say that a degenerative meniscal lesion that is visible on an MRI is suggestive of early osteoarthritis. Visible meniscus tears and extrusions appear to be associated with the progression of symptomatic knee OA. Athletes and others who subject their joints to considerable wear-and-tear may be the most at-risk. In a 2017study, researchers found that both elite and non-elite soccer players, elite-level long-distance runners, competitive weight lifters, and wrestlers all had an increased prevalence of knee OA.

Clinical researchers have even identified an average timeframe from a person’s initial meniscal injury to the development of OA. A study of more than 1,000 patients found that people who had experienced a meniscus injury between the ages of 17 and 30 showed radiologic signs of OA averaging 15 years after their original injury. People who had had a meniscal tear or injury after the age of 30, however, saw radiologic signs of OA within 5 years.

People With OA Are Also At Risk of Meniscus Injuries

Meniscal tears can also result from the degeneration of knee cartilage, a process common in OA. Research conducted by clinicians in Sweden found that “A degenerative meniscal lesion is often associated with early-stage knee OA, a disorder also involving the meniscal tissue. The tear may thus represent the first ‘signal’ feature of OA.”

In one study involving 41 women over age 40 who had been diagnosed with OA, researchers found that 73% also had a meniscal tear. And researchers from the Arthritis Center at Boston University Medical Center found that up to 91% of patients who had symptomatic knee OA also had MRI evidence of a meniscal tear.

Does a meniscal tear mean more pain for the OA patient? Research is mixed on this: some studies have shown that patients who had both a meniscal tear and symptomatic OA experienced similar levels of pain as patients who had OA but no meniscal tear.

The U.S. government has been so concerned about the possible link between OA and meniscal injuries and vice versa, that it launched the MeTeOR Trial (Meniscal Tear in Osteoarthritis Research) study, which included seven U.S. medical centers. Researchers in the MeTeOR trial found that many people dealing with both knee OA and a torn meniscus may find participating in Physical Therapy at the outset of their condition to be better than immediately opting for a meniscal repair involving arthroscopic surgery. This is especially promising news, because some researchers have found that the surgical procedure – known as arthroscopic partial meniscectomy – may actually accelerate the development of OA. According to the Mayo Clinic, more than 300,000 knee arthroscopies are performed each year in the United States on patients who have a meniscal tear and osteoarthritis in the same knee compartment.

Yet researchers in one study conducted in 2017 found that for people who already had knee OA, partial meniscectomy was associated with greater risk of worsening cartilage damage. Alarmingly, a study from the Netherlands involving nearly 5,000 patients found that in people with knee OA, “arthroscopic knee surgery with meniscectomy (was) associated with a three-fold increase in the risk for future knee replacement surgery.”

Finally, a study of patients who had both a symptomatic meniscal tear and OA found that having the arthroscopic procedure followed by supervised exercise was no better than supervised exercise alone in terms of reducing knee pain, improving knee function and improving overall quality of life for OA patients.

Looking for clarity? Brace yourself for this…

Whether or not you are facing the possibility of surgery to address a meniscal issue, if you are among the thousands of patients seeking options for how to relieve OA knee pain, consider off-loader bracing. The Unloader One® Brace from Össur, for example, has been clinically proven to reduce the pain associated with unicompartmental osteoarthritis of the knee without negative side-effects. Patients wearing the brace have also reported a reduction in pain medication. So ask your physician if an Unloader brace could be an option for you, and spread those wings again.