You're dynamic, active, in the prime of life! But every now and then, your knee twinges during sport. Could it be osteoarthritis? After all, you don't quite see yourself as someone with a joint replacement. Or not yet, anyway. And besides, what about liquid cartilage? Isn't osteoarthritis just a myth anyway?
Let's try to stay calm amid the general noise of social media and focus on the facts, as far as they are known.
Your Knee Joint: Mobile. Stable. Low Friction.
Our joints are marvels of efficiency. A mirror smooth layer of cartilage covers the joint facing ends of the bones and, thanks to its unique mechanical properties, provides remarkably low friction. Muscles stabilize and move the joint, while ligaments guide it along the correct plane.
The knee is also guided and cushioned by two wedge shaped menisci. These crescent shaped, fibrocartilaginous wedges fill the gap between the rounded end of the thigh bone and the flat surface of the shin bone, thereby increasing the contact area within the knee and distributing pressure.
What Exactly Is "Osteoarthritis"?
Osteoarthritis refers to the wear of a joint, which typically begins with mild degenerative changes and can progress to complete joint destruction. Joint wear is characterized by a progressive thinning of the cartilage. Naturally, however, all the structures described above are affected in osteoarthritis.
The joint lining can become inflamed and thickened, further wearing down the cartilage. Bone spurs can form, which can rub against cartilage and ligaments. The ligaments and menisci that stabilize the knee can loosen, which can lead to instability.
The cause of osteoarthritis is, like everything in life, multifactorial. However, mechanical stress plays a significant role, and an injury can accelerate the wear process.
Does an Arthritic Joint Always Hurt?
No, an arthritic joint doesn't always hurt. Why a joint hurts isn't entirely clear, but inflammatory changes, mechanical load, and instability are what turn an arthritic joint into a painful arthritic joint.
Treatment Options
Every therapy begins with a diagnosis. Understanding the changes described above allows for treatment tailored to the individual wear pattern of your joint. Unfortunately, a cartilage regenerating therapy does not yet exist.
Inflammation can be reduced with medication, either as tablets or injections into the joint.
Load on the joint can be reduced, for example by adapting the type of sport practiced. A change in the mechanical loading axis can be achieved with insoles and braces. In some cases, however, surgical bone correction of a mechanically unfavorable "bow legged" or "knock kneed" alignment is recommended.
Joint stability can be improved through physiotherapist guided strength and coordination training. Torn portions of the meniscus can be surgically repaired, and loosened meniscal attachment points can be refixed (see image).
Blocking cartilage or meniscus fragments, abrasive bone spurs, and scarred synovial tissue must be surgically removed.
Only when we, as physicians, no longer expect joint preserving measures to significantly improve your symptoms do we recommend artificial joint replacement. We use computer assisted planning and verification of the surgery with MAKO technology, in which bone cuts are performed using a robotic arm assisted saw. Through this technique, we aim to achieve better function of your knee, so that you too can stay calm and stay active!