What is a total knee replacement (TKR) exactly? If you’re looking for a medical textbook definition, stop reading because you might get upset. My goal is an easy-to-understand, conceptual explanation. This means avoiding medical jargon that even some doctors find confusing – and maybe even making a car reference.
Let’s start with a simple fact: knees bend. When knees bend during walking, bones must glide on one another to produce movement.
If you’ve ever rubbed your hands together really fast (think of Mr. Miyagi healing the injured Karate Kid), friction and heat are produced, and if you keep going, you’ll injure your skin, producing pain. Now imagine your knees producing this amount of friction when the bones glide against one another while bending. You wouldn’t get far before your knees would start to burn!
Why doesn’t this happen? The answer is: articular cartilage (AC). OK, it’s medical jargon, but it’s necessary as it’s crucial to understanding a TKR. AC provides a virtually frictionless surface for the knee bones to glide during bending without producing friction, heat, or pain. In fact, there’s less friction in your knees during bending than there is between two pieces of ice sliding across each other. Amazing, right? Sorry about that nerdy moment, but this is why you can bend your knees, walk, or run without injury or pain.
Here’s where we encounter problems. If you start losing your AC, commonly due to age and “wear and tear” (called osteoarthritis), you can begin experiencing pain. Once you lose a significant amount of AC and pain is affecting the quality of your life, even after conservative treatment, your doctor may recommend a TKR.
So, what the heck is a TKR? Think about how we reached this point. We lost our AC, which causes pain. Currently we don’t have the ability to regenerate AC lost from osteoarthritis; we can only replace it with an artificial surface. During a TKR, all we’re doing is removing the worn-out AC and replacing it with new, artificial materials (metal alloys and polyethylene) that reduce friction.
We don’t change the muscles powering your knee or the major ligaments that provide stability, nor do we remove large amounts of bone. We merely replace what was lost and restore balance to your knee. Simply put, a TKR is like changing the tread on your car’s tire.
Find out why Casa Colina Hospital and Centers for Healthcare recently received a Five-Star Rating in the category of “Total Knee Replacement” based on performance and quality data evaluated by Healthgrades. Join Dr. Corrales for a free community seminar entitled “Setting a New Standard in Total Knee Replacement Surgery” on Wednesday, September 11, from 6:00-8:00 PM at Casa Colina Hospital and Centers for Healthcare. To reserve your space, call (866) 724-4132. For more information on its Revive Joint Replacement Program, visit www.casacolina.org/move.