First up, we hate the degeneration word. More on that later.
You’ve had your MRI scan, your specialist probably suggested surgery. (If not, you wouldn’t reading this – we don’t think.) You are worried and you want to know more. Today we share with you three things in your MRI that do not matter.
When it comes to knee pain, MRI is indeed the most reliable, non-invasive diagnostic technique. Your specialist would have probably mentioned technical terms such as meniscal tear or degeneration, cartilage defect, osteophytes, and all the rest of it. (To avoid confusion, these findings are collectively known as osteoarthritic or degenerative features/findings.) It may seem very scary but do you know there is no established relationship between these awful-sounding MRI osteoarthritic (“degenerative”) findings and knee pain? To date, we are still uncertain of the clinical benefit of knee MRIs.
Before we go on, you should note that people WITHOUT knee pain (or any symptoms at all) probably have one or more of the your MRI features in their knees too!
Knee Osteoarthritis? Your Age Matters
It is important to put your MRI into your personal context. If you are 40 years old and above, it is expected that you would present with some osteoarthritic changes. In fact, these changes are normal age-related changes and NOT associated with pain. As you grow older, you get more and more of such changes happening in your knees. By the time you are 70 years old, over 75% of people WITHOUT knee pain would have a cartilage lesion.
Take home message #1: the older you are, the more likely your MRI findings are perfectly normal age-related changes. This means undergoing surgery to correct for these “defects” would not actually change your pain experience. More on this at the end!
Articular Cartilage Defects
Remember the last drumstick you ate? As you reach the ends of the drumstick, there is a crunchy bit. It is a hard, white layer that goes over the ends of the bones like some sort of cap. That is the articular cartilage of the chicken. You have them in your knees too!
So how common is an articular cartilage defect? According to a 2018 study looking at 4322 knees from 3446 participants (that is a large sample size by the way), 24% of people WITHOUT knee pain would have one. If you are under 40, 11%. If you are over 40, this goes up to 43% (almost one in two).
While cartilage defects may sound serious, just because you have one doesn’t mean your knees are defective! Remember, many people without pain do have them.
Same thing, it’s common for people with asymptomatic knee to have meniscus tears. The same analysis looked at 3761 knees from 2817 individuals found 10% of them had a meniscal tear despite having a symptom-free knee. For individuals below 40 years old, 4% of asymptomatic individuals would have a meniscal tear. This goes up to 19% for those 40 and above. Like before, the prevalence of meniscus tears also increases with age.
Osteophytes are little bony growth that occurs at the joints and it is a key characteristic of osteoarthritis. Not surprisingly, the prevalence of osteophytes increases with age. Out of 3257 symptom-free knees from 2499 participants, 25% of them had osteophytic findings in their MRIs. For those under 40 years old, the prevalence is 8% and this increases to 37% for those 40 years old and above.
Why we are telling you this?
Because having “degenerative” changes in your knees is not the end of the world. In fact, it might not mean very much at all. A 2018 commentary by David Hunter in prestigious journal Rheumatology printed “archaic terms such as wear and tear and degenerative are now considered both pejorative and inaccurate.”
Data is consistently showing that osteoarthritic changes in MRI – what was previously misunderstood as wear and tear – are more likely to be normal and harmless age-related changes no different from wrinkles and greying hair. So when you see words like cartilage defect, meniscus, or osteophytic changes, don’t freak out. Take a deep breath and remember it’s nature playing itself out!
Best part of it all? Knee arthroscopy, the most commonly performed orthopaedic procedure in the world, doesn’t work. A study performed in 2013 looking at partial arthroscopic meniscectomy vs. sham surgery found patients who underwent the meniscectomy procedure did not perform better those who had the sham surgery. A follow up study looking at the subjects two years after the procedure found that the meniscectomy did not improve knee pain or function even for those who were not responsive to conservative care.
Another study published in 2017 in the prestigious British Medical Journal also knee arthroscopy (compared against conservative care) to offer no benefit in improving either pain or function.
So, are you considering knee arthroscopy?
If so, what makes you think you will respond differently from the rest?