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Home > Arthrosis, Arthrotides and Arthritis – What is the Difference in these Conditions?

Arthrosis, Arthrotides and Arthritis – What is the Difference in these Conditions?

Dr. Bob Snyder
Robert J. Snyder, M.D.


As a busy Orthopaedist, I often have patients ask me about medical terms that they see written in their charts and express their confusion over them.  They wonder how they can possibly have two or three conditions that sound and look alike at the same time.  In this article, I hope to clear up some of the confusion about some commonly used orthopaedic terms and help you understand why they are used.

What you will notice in common with all three of these medical terms is the root word “arthro”, which comes from the Greek and refers to the joints of the body.   When you add the suffix “osis”, meaning diseased state, you get the term arthrosis, meaning diseased state of the joints.  When you add the suffix “tides”, it means a physiologic variation or increase of a certain constituent in body fluids.  So then, arthrotides means an increase in the amount of synovial fluid within the joint, aka, a swollen joint full of fluid.  Add the suffix “itis” meaning inflammation, and you get arthritis, meaning inflammation of the joint.

Often, the terms arthrosis and arthritis are used interchangeably, as they both refer to the type of arthritis that we know as osteoarthritis.  This is the common, wear-and-tear arthritis that most of us will get if we live long enough, where the cartilage on the ends of our bones in our joints will break down over time, causing pain and stiffness.  Genetics plays a big role in whether or not we develop significant arthritis, as does obesity, our fitness level, our general health and other factors.

We treat arthritis conservatively with non-steroidal anti-inflammatory medications, exercise, weight loss, activity modification, the use of ice and heat, physical therapy, steroid injections, visco-supplementation injections, arthroscopic surgery, and finally joint replacement, if necessary.

However, not all people who have arthrosis/arthritis develop arthrotides.  Arthrotides develops as the body’s way of trying to protect a joint from the loss of cartilage and the subsequent bone on bone irritation that results.  All joints have a natural lubricant in them called synovial fluid.  This fluid helps to keep the cartilage hydrated, healthy and our joints in working order.  In a healthy joint, there is never too much, nor too little synovial fluid, but just the right amount.

When a joint has arthritis and the cartilage wears away, the ends of the bone start rubbing against one another causing irritation and inflammation.  The body may grow bone spurs, called osteophytes, as a way of trying to relieve the pressure and decrease the load off one area of the bone.  It may also increase the amount of synovial fluid in the joint, again in an effort to reduce the irritation.  When this happens, the joint capsule swells, and may feel warm and stiff.  This is the condition of arthrotides.  We most commonly see this in the knee, but it can certainly happen in other joints as well.

So, if a joint fills up with fluid, why not just draw it off with a needle and be done with it?  Because the joint will just fill up with fluid once again and you’ll be right back where you started, with a stiff and swollen joint.  When I take the fluid off of the joint, I replace the fluid with a steroid medication to help the joint to heal and to reduce the inflammation within the joint.  It is a temporary fix, but some patients get months of relief from these injections. Patients who have arthrotides tend to progress on to joint replacement sooner rather than later than other patients who have arthritis without arthrotides, but that is not always the case.

These three conditions often go hand in hand, but I hope this explanation helps you to understand the differences in them and why the terms might be used in your medical chart.

Make an appointment with Dr. Snyder or another OSC provider by clicking the “Request Appointment” button below or by calling (757) 596-1900.  

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