My knee is “bone on bone” — now what?

Knee arthritis affects 10 to 13% of the US population over age 60

If a doctor has told you that you have arthritis, you might think there’s nothing that can be done about it. However, what we’ve learned in recent years shows the opposite. You can treat arthritis and you may be surprised by what research has shown to be the best prescription — exercise.

Common symptoms and diagnosis

Common symptoms include pain localized to the joint, stiffness, loss of flexibility, a grinding sensation, swelling, feel weaker, and tenderness to touch. In order to make a clinical diagnosis, a physical examination and imaging studies (usually x-rays) are utilized. Knee OA may occur in any or all of the three compartments in the knee (inside, outside, between kneecap and thigh bone). An important note with the use of imaging, is that the x-ray does not always correlate perfectly to the symptoms one may feel. This may be with significant joint changes and minimal pain, as well as minimal joint changes and significant pain experienced.

What is osteoarthritis (knee) and what is the cause?

Osteoarthritis is a condition in which the cartilage, or cushioning on the end of bones, deteriorates over time.  This leads to changes in bone structure and alignment, while also affecting all the structures associated with the specific joint. Knees are one of the most common joints affected by osteoarthritis, so what really does cause knee arthritis?  There are many different factors including mechanical, metabolic health, and previous injury or surgery. 

Metabolic

Dietary factors may play a bigger role in arthritis than we once thought (1). Inflammation from a poor diet and other metabolic factors may lead to inflammation that affects cartilage and bone. Weight loss, diet changes, and exercise can change these markers and in turn, change the symptoms of OA.       

Mechanical

The concept that OA is an unavoidable aging process of “wear and tear” or “degenerative joint disease” might be better thought of as “wear and repair”. Our bones are constantly breaking down and building up according to the stresses the joint is exposed to on a regular basis. Heavier manual jobs may increase the incidence of knee OA. A common myth is that running takes a terrible toll on the knees and will cause arthritis. However, recreational runners have 70% less arthritis than someone who is sedentary. This illustrates there is not likely a finite lifespan for our joints, and many other contributors for arthritis than just wear and tear. 

Injury/Surgery

Previous knee injury or surgery such as an ACL tear/repair or meniscus tear may cause arthritis earlier than in someone who has not had a surgery. Again, researchers think this may be due to inflammation in the joint induced by the injury, and also the inflammation that occurs as a result of the surgery.

Treatment options

Surgery

The British Medical Journal advises that people go through conservative treatment, including physical therapy and exercise prior to having a surgery.  As you can see here, the outcomes at 1 to 2 years are the same whether people have surgery or not and there are fewer adverse events (illness, infection, DVT).  Partial or total knee replacements are always an option for end stage arthritis with significant pain, but the new hardware doesn’t last forever, so it is best to use your other options as you cannot go backwards from this.

Injection

A recent study looked at whether a course of physical therapy or coticosteroid injection led to better improvements in pain and overall function.  They found that both groups improved about the same over the course of 4 weeks, while those who attended physical therapy saw those effects last out to 1 year after the study while those in the injection group did not maintain the initial gains to the same extent.  

Stem Cells or PRP

Stem cells from bone marrow or adipose (fat) tissue and platelet rich plasma (PRP) are newer options (not currently covered by most insurance carriers) that show some initial promise in helping with knee OA symptoms. It’s such a new technology that we’re still studying what the effects are and what the best treatment is after the injection to maintain it.   Physical therapy can help determine what is most appropriate for your given situation. 

Exercise

Now that we know appropriate movement and exercise is beneficial in treating knee arthritis, the question becomes what exercises work best.  That will be based on your individual situation and a full assessment with your therapist to find the best ways to work and stay active.  There will likely be a combination of exercises and treatments focusing on the knee itself, as well as working on mobility, strength, and control throughout the rest of the body that may change how forces are transferred through the knee.