In our practice we call knee replacement the surgical amputation of the knee joint with insertion of a prosthesis. Why? It’s a very big surgery with a 1 in 10 chance of serious, life changing complications; and a very good reason for a good knee replacement alternative. In 2008 alone, there were 17,500 huge complications (including 5,000 deaths) due to knee replacement surgery just in Medicare patients. Despite this, by 2015 1.4 million of these surgeries will be performed annually due to a 45% lifetime risk of knee arthritis. As a result, early detection is important, which is what a recent study sought to better understand. The authors took knee x-rays of more than 500 patients every 5 years. Women with mild to moderate arthritis on x-rays in their 50’s (KL grade 1 or 2) had about a 50/50 chance of needing a knee replacement 15 years later. Women with no arthritis on x-rays in their 50’s only had about a 1 in 100 chance of needing a knee replacement 15 years later. Heavier patients were more likely to progress. Other studies have shown that heavier patients also have worse outcomes after knee replacement surgery. While all of this seems to make sense, what was really interesting is that the majority of the women who actually got a knee replacement by year 15 didn’t actually have mild or moderate arthritis at the time the study began-indicating yet again that images like x-rays are a poor surrogate for pain. This last point is very important, as we often see patients who are transfixed by their MRI images as if they were the modern Oracle of Delphi. This study and many others like it show that the pain you experience and what’s seen on images are often likely two different things-so take any x-ray or MRI result with a grain of salt! In addition, don’t forget that about 15% of patients who have their knees replaced still have pain despite the surgery!
About the Author
Christopher J. Centeno, M.D. is an international expert and specialist in regenerative medicine and the clinical use of mesenchymal stem cells in orthopedics. He is board certified in physical medicine as well as rehabilitation and in pain management through The American Board of Physical Medicine and Rehabilitation.…