The Number of Knee Replacement Risks Increases

A recently published study out of Sweden looked at the medical records of the “entire Swedish population born between 1902 and 1952.” Of those receiving knee replacements, the risk for hip fracture before surgery was low. There was a total of 3,221 patients who had a hip fracture within 10 years following knee replacement, and this accounted for a 4% increase in hip fracture risk following knee replacement.

Given what we know about knee replacement, the increased hip fracture risk may be due to something simple like increased activity after knee replacement. However, I’d bet on other factors. For example, could this be related to the metal ions or plastic elements of the knee replacement devices hurting bone in other areas?

Learn More About Regenexx® Procedures
Request a digital booklet and more information to learn about alternatives to orthopedic surgery and the Regenexx patient experience.
We do not sell, or share your information to third party vendors. By submitting the form you agree that you've read and consent to our Privacy Policy.

What Are Other Known Risks of Knee Replacement?

X-ray total knee replacement on both knees

Total knee replacement on both knees. Tridsanu Thopet/Shutterstock

Over the years, I’ve written a lot about the alarming number of knee replacement risks. It’s a topic I cover regularly right here on this blog. You can’t simply amputate the knee joint, saw off a good chunk of the long bones that connect to the joint, and replace it all with a fake joint and bone and not have issues to contend with. There’s nothing simple about it, and the stunning fact is that one-third of knee replacements are unnecessary. So what are knee replacement risks outside of hip fractures? Let’s review a few of these.

Build Up of Metal Ions After Knee Replacement

When a knee is amputated, it is replaced with a prosthetic knee made of metal, ceramic, plastic, or some combination of these materials. These devices shed wear particles with movement, and we know that in some patients, metal ions from the knee replacement device can build up in the blood. In patients who have, for example, a jewelry allergy, there is a high risk of being allergic to the metals used in these knee replacement devices. The new plastics in knee replacement prostheses can also cause allergies. If you are allergic, the device is more likely to fail, cause chronic pain, or need to be replaced sooner.

Another study, which I covered this past December, shows that these knee replacement risks aren’t just confined to those select patients with known metal allergies; this study suggests that this risk may encompass all patients who have an allergy to anything. Why? Allergic people may be much more sensitive to a foreign body (the knee prosthesis) shedding particles as it wears. This can result in their immune system attacking and, therefore, rejecting the device. The result: swelling, pain, and poorer bonding of bone to the device.

Heart Attack and Stroke After Knee Replacement

With knee replacement being such an extensive and extreme surgery, it’s not surprising that so much trauma from knee replacement can cause severe complications like blood clots, heart attacks, and strokes. Why does this happen? When you completely chop out a joint, there is severe trauma to the blood vessels and bone marrow space. This likely leads to a higher risk of blood clots, and these blood clots can obstruct vessels in the heart, leading to a heart attack. The stress alone of undergoing the joint amputation, for some patients, maybe enough to trigger a heart attack.

Ongoing Pain After Knee Replacement

What are knee replacement risks with regard to pain? Knee pain after knee replacement is the most common complication patients report. Considering knee pain is the driving force that leads patients to decide on the surgery in the first place, this particular one of the knee replacement risks is perplexing. With patients reporting pain levels of 3, 4, and even 5 out of 10 (by the way, 5 out of 10 isn’t much different from the level most patients report prior to knee replacement), this drastic surgery that many patients view as their final option to relieve their knee pain really isn’t helping much, and it adds a bagful of risks on top of that.

In addition, some studies have shown pain rates and percentages following knee replacements even higher at two, three, or four years following surgery, which seems to imply a trend toward pain worsening as time goes on, not getting better. And the frightening thing is, your knee might not be the cause of your knee pain at all. Your knee pain could be caused by a loose ligament, or your knee pain could even be due to a problem in your lower back.

>> Alternatives to Knee Replacement Surgery  
>> Regenexx Knee Patients’ Registry of Outcomes – Over 11,125 tracked nationally
>> Before and After MRI Knee Images

Activity Level After Knee Replacement Isn’t What the Ads Imply

Last October, I discussed activity levels following a knee replacement. This is another big reason people choose a knee replacement: they think they’ll be going for runs on the beach or playing volleyball with their grandkids…just like the TV commercials imply. The study I highlighted examined activity levels after hip or knee replacement and concluded that few people return to the types of activity they desire. In fact, only 5% or less achieved anything approaching normal physical activity! Multiple studies support the fact that after knee replacement, patients rarely get back to the types of activities seen in TV or magazine ads.

The upshot? While there may be some extreme cases that do require a knee replacement, a large percentage of knee-replacement candidates can explore regenerative-medicine options, such as stem cell injections, that may be able to relieve their pain and increase their activity level without cutting out their knee? Why go through a drastic, invasive surgery that’s associated with so many ongoing knee replacement risks when there may be a nonsurgical solution that will allow you to just say no to knee replacement?

Chris Centeno, MD is a specialist in regenerative medicine and the new field of Interventional Orthopedics. Centeno pioneered orthopedic stem cell procedures in 2005 and is responsible for a large amount of the published research on stem cell use for orthopedic applications. View Profile

If you have questions or comments about this blog post, please email us at [email protected]

NOTE: This blog post provides general information to help the reader better understand regenerative medicine, musculoskeletal health, and related subjects. All content provided in this blog, website, or any linked materials, including text, graphics, images, patient profiles, outcomes, and information, are not intended and should not be considered or used as a substitute for medical advice, diagnosis, or treatment. Please always consult with a professional and certified healthcare provider to discuss if a treatment is right for you.