What Is Subchondral Sclerosis?

This condition is often seen on X-rays of people with osteoarthritis

Doctor pointing at hip joint. Credit: Jan-Otto / Getty Images


Subchondral sclerosis is a painful condition that affects people who have osteoarthritis. Fortunately, it’s easily detected and there are several treatment options available. 

To understand what subchondral sclerosis is, it’s useful to have a clear picture of how osteoarthritis affects the joints of the body. Not only does osteoarthritis degrade the cartilage in a joint, it also wears away at the subchondral bone underneath the cartilage.

As the body tries to regrow this bone, it comes back thicker than before, resulting in subchondral sclerosis. It’s most likely to be found in later stages of osteoarthritis. 

Subchondral sclerosis can cause bone spurs, and in some cases, can reduce motion in the affected joint. 

How is Subchondral Sclerosis Detected?


When you have an X-ray done to diagnose osteoarthritis, subchondral sclerosis is one of the things the radiologist is looking for. It shows up on X-ray as a denser area of bone just under the cartilage in your joint, appearing as abnormally white bone along the joint line. 

Subchondral sclerosis is seen in osteoarthritis in many of the commonly affected joints, like the knee, hip, spine, and foot. 

What Does Subchondral Sclerosis Mean for Osteoarthritis? 


Subchondral sclerosis doesn’t usually predict how osteoarthritis will progress. So don’t assume that your osteoarthritis is getting “worse” if you’re diagnosed with subchondral sclerosis.

A study in 2014 looked at whether subchondral sclerosis detected by MRI (magnetic resonance imaging) was associated with loss of cartilage. They enlisted 163 people with knee pain and followed them for three years with baseline knee X-rays and MRI examinations. They found no significant associations between baseline subchondral sclerosis and increased risk of cartilage loss in the same region of the knee.

Another study published in 2014 examined whether subchondral sclerosis was actually protecting the knee from joint space narrowing in patients with varus knee osteoarthritis (people with this condition used to be referred to as "bow-legged" since it causes visible differences in the knee and leg).

The researchers in this study looked at 192 women who had already been diagnosed with varus knee osteoarthritis and conducted knee radiograph, dual-energy X-ray absorptiometry at the lumbar spine, proximal femur, and knee condyles. The study concluded that the increase in subchondral bone sclerosis might protect the decrease of cartilage thickness, which is what causes pain for many people with osteoarthritis.

How is Subchondral Sclerosis Treated?

Much like osteoarthritis, there isn't a cure for subchondral sclerosis. But there are steps you can take to slow its progression and reduce painful symptoms. Low-impact physical exercise, including using a stationary bike, yoga, and swimming are excellent ways to keep the affected joints active. In patients who are overweight, losing weight, which can reduce the stress on joints, is also recommended.  

Your healthcare provider may also recommend physical therapy, hydrotherapy, or more holistic medical treatments like acupuncture.

Anti-inflammatory medications such as ibuprofen also may be recommended. For more serious cases, there are prescription medications that can provide relief. 

In general, anything that relieves osteoarthritis symptoms will help subchondral sclerosis symptoms as well.

In some severe cases, surgery to remove the excess bone growth may be recommended. 

As with any chronic condition, consult with your healthcare provider to figure out the best course of treatment for your symptoms.

Sources:

Y. Akamatsu, H. Kobayashi, Y. Kusayama, K. Kumagai, N. Mitsugi, T. Saito. Does Subchondral Sclerosis Protect Progression of Joint Space Narrowing in Patients with Varus Knee Osteoarthritis? Osteoarthritis and Cartilage 2014.

Crema MD, Cibere J, et. al. The relationship between subchondral sclerosis detected with MRI and cartilage loss in a cohort of subjects with knee pain."   National Institutes of Health/Osteoarthritis and Cartilage. April 2014

Guangyi Li, et.al. "Subchondral bone in osteoarthritis: insight into risk factors and microstructural changes National Institutes of Health/Arthritis Research & Therapy, 2013.

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