Osteoarthritis 101

Rachel Proctor, PT, DPT

I hear the term osteoarthritis, or simply arthritis, every day from my patients.  It is a term that comes with lots of connotations and preconceived notions, many of which are at least partially inaccurate.  Phrases like “bone on bone” and “wear and tear” are spoken often in my office.  Honestly, I would be happy to put these phrases to rest and remove them from the lexicon.  We will unpack these phrases, but first – what is osteoarthritis anyway?

What is osteoarthritis?

Osteoarthritis is a thinning of the cartilage that serves to cushion the joint.  It is often accompanied by evidence of osteophytes (bone spurs) and joint space narrowing on an x-ray. 

What causes osteoarthritis?

The cause of osteoarthritis continues to be studied, but we have enough evidence to say that it is not simply wear and tear on a joint.  If it was truly wear and tear, then every sedentary person who never exercises should have flawless cartilage in their knees.  That is not the case.  We now know that moderate levels of exercise can have a protective effect on the cartilage in your knees and make you less likely to develop knee osteoarthritis.  Studies comparing runners to sedentary non-runners found that individuals running a few miles per week were less likely to develop osteoarthritis. 

How can osteoarthritis be found?

Not every person who has evidence of osteoarthritis on an x-ray will have knee pain.  Many more factors such as lifestyle, sleep quality, stress, diet, and activity levels will have an affect on pain levels.  Even if you have osteoarthritis in your knees, you can decrease pain and improve function with a light-moderate exercise program.  For some, a consistent walking program can help improve strength, pain, and function.  For others, they may prefer Tai Chi or a group exercise class.  A physical therapist can also help tailor an exercise program for your specific needs. 

We now know that wear and tear is not the best way to describe osteoarthritis.  What about the phrase bone on bone?  This phrase comes from the appearance of the knee joint with advanced osteoarthritis.  There will look like there is no joint space between the femur and tibia, resulting in what looks like bone on bone on the x-ray.  The phrase often invokes fear and the immediate thought that a joint replacement is inevitable.  Again, the way an x-ray looks will not predict with any certainty how much pain you have or how much difficulty you will have with things like walking or negotiating stairs. 

An x-ray will give your physicians valuable information regarding potential next treatment approaches, but it should not invoke fear of inevitable surgery.  The decision to have surgery should be a decision you make in conjunction with your physician.  How limited are you functionally? Have you tried conservative treatment such as an exercise and strengthening program?  You may conclude that a joint replacement is the appropriate next step, but the decision should be made based on your whole lifestyle and functional requirements.  It should not be a decision made solely on the way your knee looks under x-ray. 

Osteoarthritis is common, but there are many effective treatment approaches to manage the symptoms.  Your physical therapist in conjunction with your physician can help guide you for what may be the next best step for you.  My goal with this blog was to dispel some of the myths and fear around osteoarthritis, specifically of the knees.  Armed with more information, you will be able to make the best lifestyle and treatment decisions for you.

As always, contact Hands On Physical Therapy with any questions. 


Alentorn-Geli E, Samuelsson K, Musahl V, et al.  The Association of Recreational and Competitive Running With Hip and Knee Osteoarthritis: A Systematic Review and Meta-analysis. J Orthop Sports Phys Ther. 2017 June; 47(6): 373-390.

Goldman B. Osteoarthritis results from inflammatory process, not just wear and tear, study suggests.  https://med.stanford.edu/news/all-news/2011/11/osteoarthritis-results-from-inflammatory-process-not-just-wear-and-tear-study-suggests.html . 2011 Nov 6 (accessed May 5th, 2020)