What Happens If You Have A Bone Bruise?

R knee bone bruise from Theinjurysource

A patient I saw recently had quite a big bone bruise on his tibia (shin bone) and femur (thigh) after tearing his ACL. They are also known as bone contusions. It is similar to a bruise you may get on your skin after a fall or when you bump into the corner of a table or chair. It can also be more serious than a bruise under your skin.

A bone bruise (or contusion) refers to blood that is trapped under the surface of your bone after an injury. Since bone is also living tissue, it can also get injured or bruised like your skin and muscles. It usually takes much more force to bruise your bone to injure it without breaking it. A bone bruise usually feels like a deep, dull and throbbing ache that's coming from deep inside the body.

We normally see bone bruises in our clinic after an acute ankle sprain or ACL tear. What's the implication of having a bone bruise? An article (Kia et al, 2020) looked at the incidence of changes on the articular cartilage surfaces on MRI five years after the ACL tear. Note that this is done without correlation with clinical and functional outcomes.

The authors found that the lateral (outside) tibia (shin bone) and femur (thigh) are more frequently involved. The area that was initially bruised sigificantly correlated with increasing chondral (articular cartilage) wear over time. The larger the bone bruise, the higher the chances of having a significant change in the articular cartilage 5 years post surgery.

Absence of a bone bruise on initial MRI was the greatest predictor of no cartilage wear at 5 years in all compartments of the knee. If there was a lateral meniscus injury, there was an increased risk of wear in the lateral tibial plateau (shin bone).

We do not know if this wear leads to pain or even the need for a joint replacement further down the road since the scans DO NOT always correspond with the patients' symptoms.

I always communicate this with the rest of my team seeing patients with bone bruises since this will affect and influence progression to activities of daily living and especially back to sport.

No one knows how long the bone bruises take to heal. In my case before I had the first of my 3 knee surgeries, the bone bruising was still seen on my repeat MRI 9 months later despite me not running or jumping while waiting for it to heal.

For the athletes, impact related activities should only be considered 16-20 weeks after surgery, especially running and plyometrics so as to decrease pain and swelling.

The patient needs to be progressed slowly to have long term success. Slower will always be better in these cases.

Reference

Kia C, Cavanaugh Z, Gillis E et al (2020). Size Of Initial Bone Bruise Predicts Future lateral Chondral Degeneration In ACL Injuries: A Radiographic Analysis. Orth J Sp Med. 2020: 8(5). DOI: 10.1177/2325967120916834.