If you have hip pain, are PRP (platelet-rich plasma) injections worth it? Will PRP injections help with knee or shoulder pain? What about your elbow or foot? Let’s see what the science says so you can make an informed decision.
We work with a lot of clients who have had chronic hip, knee, back, and shoulder pain. Our clients have usually spent all kinds of money and time trying to fix their aches and pains with massage, chiropractic, physical therapy, dry-needling, acupuncture, etc. etc.
When those approaches fail to help, people often get desperate. And that’s when PRP injections pop up on the radar.
The premise of PRP injections is that all you need to do is pull some blood out of your body, make it richer in platelets by spinning it around, and then inject the super-charged blood back in so it can promote faster healing! This sounds high tech, simple, and easy. And if a doctor suggests it, it must work, right?
As trainers who focus on muscle balance and proper movement patterns, we’re generally not huge fans of PRP injections for two big reasons:
In short, if you believe that the only one who can fix your problems is someone else, you’re in for a very long and frustrating road. If you instead start with the assumption that there’s something YOU can do to positively affect your situation, you will be much better off.
That means avoiding pain treatment strategies that imply that your body is damaged beyond all normal human healing capacity.
“But I have arthritis, a labral tear, or some other major issue with my body,” you may be saying.
Science shows that alleged structural problems like arthritis, labral tears, etc. show little to no link to people experiencing pain. There’s a whole lot more going on when you experience pain than just plain “tissue damage.” .
So, let's talk about the effectiveness and questionable science around PRP injections.
There are two main reasons doctors sell PRP injections to their patients. One is for persistent pain that they blame on soft tissues (like muscle or tendon). The other is for joint degeneration (like arthritis, chondral lesions, cartilage loss, etc.).
When you have pain in a muscle, tendon, or ligament, doctors may suggest that this is due to damage in the soft tissue itself. If it continues to hurt for a long period, they suggest that the soft tissue is having trouble healing. By injecting platelet rich plasma into the site, you’ll increase the speed at which the soft tissue heals.
This would be fantastic! Imagine the implications for healing after an injury or a surgery! ACL torn? Achilles ruptured? Hamstring torn? A PRP injection may be all you need to speed up that healing process!
Lab experiments on muscles and tendons indicate that PRP may actually speed up healing in these tissues. However, it also appears that PRP may have the reverse effect on ligaments. It’s all quite murky.
A review on PRP studies by Cochrane in 2014 summarized the state of evidence on PRP: "Overall, and for the individual clinical conditions, there is currently insufficient evidence to support the use of PRT (Platelet Rich Therapies) for treating musculoskeletal soft tissue injuries."
A more recent review of PRP research in 2017 concluded: "it appears that PRP may provide some benefit in patients who have knee osteoarthritis and lateral epicondylitis. On the other hand, the evidence appears to be inconsistent or displaying a minimal benefit for PRP usage in rotator cuff repair, patellar and Achilles tendinopathies, hamstring injuries, ACL repair, and medial epicondylitis.”
The overall picture is rather bleak for PRP and soft-tissue issues. PRP is just not that useful for pain that allegedly comes from soft-tissue damage.
So PRP for soft-tissue seems to be a non-starter. But what about for arthritis?
There is some evidence that PRP injections might be helpful for knee arthritis. One of the very best studies available on PRP for knee osteoarthritis compared PRP injections to placebo saline injections (Patel 2013).
They found that the groups of patients receiving PRP injections did better than the group that received saline injections! They also found that the positive results started to diminish at the six month follow up. And since there was no follow up after six months, nobody knows how they did in the long term.
Many new-fangled orthopedic treatments go through this same lifecycle. Someone introduces it to the market. For years, it's difficult to find any high quality studies. Then after many more years, it's hard to find any long term studies to demonstrate any lasting benefit.
By the time anyone gets around to doing high quality, long term studies, the treatment is already so popular that everyone believes it works (even if it is no better than placebo). See knee meniscus surgery as an example.
But there’s a much larger question to address when thinking about PRP for arthritis.
This may sound silly, but it’s a crucial question. Conventional medical approaches to pain assume one thing. Pain means damage. If it’s pain in the joint, it’s joint damage.
And what is joint damage? Osteoarthritis.
The story is simple. Your bones are degenerating as they rub against each other. This causes pain. You can verify this in an X-ray. However, research consistently shows that the severity of arthritis in an X-ray has NO LINK AT ALL to the experience of pain.
Put another way, you can show “bone on bone” arthritis in an X-ray, and have no symptoms. Cartilage damage, labral tears, tendon damage - you name it, and it has an inconsistent link (if any) to the experience of pain.
Let's repeat that one more time. Even if you have terrible, awful, grade 4 osteoarthritis in an X-ray, you may actually experience ZERO symptoms.
Basically if you have NO signs of arthritis in an X-ray, you may still have symptoms of pain and immobility. No, I'm not just making this up.
Researchers have done multiple studies on knee osteoarthritis on thousands of people and found that there is no link between severity of arthritis on X-ray and knee pain (Hannan 2000).
In addition, a significant percentage of people with completely asymptomatic, pain-free knees show signs of knee osteoarthritis (Culvenor 2018). The numbers are actually huge.
In asymptomatic adults under 40, 4-14% show signs of knee osteoarthritis. In the over 40 population: 19-43% show signs of knee osteoarthritis.
Let’s look at an analogy. Let's assume 25% of adults over the age of 40 drink soda in the United States. Let's say we suspect soda drinking is what causes knee problems.
Now let’s do some research studies.
Group A: 1000 adults with knee problems. 25% of them drink soda.
Group B: 1000 adults with no knee problems. 25% of them drink soda.
Is soda the cause of their knee problems? Can't say that it does. It seems to have no effect at all.
Let’s do another study with a different set of random people.
Group A: 1000 adults with knee problems. 45% of them drink soda.
Group B: 1000 adults with no knee problems. 25% of them drink soda.
Is soda the cause of their knee problems? You might be tempted to say “More people with knee pain drink soda!” But that doesn’t mean it’s the soda causing the knee pain. There might be some correlation, but it's unclear.
Remember the old adage: "correlation does not equal causation."
After all, in another study, you could discover this:
Group A: 1000 adults with knee problems. 37% of them drink soda.
Group B: 1000 adults with no knee problems. 35% of them drink soda.
The numbers can fluctuate simply from the randomness of the individuals in the groups. If the soda is actually the cause of the knee problems, you'd expect to see something like this...
And even then you wouldn't have a slam dunk case! There could be some other variable you don't realize is affecting things. Maybe people who drink soda are less likely to exercise? Or maybe they're more likely to participate in activities like soccer and football that can potentially be more strenuous on the knee?
But you always want to look at large groups of people without symptoms to see if the variable you suspect is actually causing the problem. If you see some dramatic differences in the numbers, you have the beginning of a strong case.
For example, if I suspect blond hair causes knee problems, I would want to see if there’s any link between blond hair and knee problems.
Group A: 1000 adults with knee problems. 17% of them have blond hair.
Group B: 1000 adults with no knee problems. 14% of them have blond hair.
Does it seem like blond hair is the problem? Probably not. The numbers are too similar. There's just no case to make here. The big problem is that many orthopedic arthritis papers don't acknowledge this problem. Instead, they say things like this:
Group A: 1000 adults with knee problems. 45% of them have X-rays that show damage. Therefore it’s the damage in the X-rays that is causing their knee pain.
Or it'll look like:
Group A: 1000 adults with hip problems. 65% of them have MRIs that show damage. Therefore it’s the damage in the MRIs that is causing their hip problems.
This flies in the face of basic logic. Many research papers cite studies like these, completely ignoring the fact that the asymptomatic population has "arthritis" and other signs of damage in X-rays and MRIs all the time in very high numbers.
In short, you have signs of “damage” that have no correlation to the experience of pain or disability throughout the pain-free population. But you still end up with invasive medical treatments to "fix" the damage and researchers perpetually barking up the wrong tree.
This isn’t isolated to just knee arthritis, of course. All kinds of allegedly iron-clad orthopedic theories about structural damage causing pain don’t hold up:
The problem is that everyday people like you and me don’t usually have the time to dig deeper into the research to see what’s going on. Truth be told, physicians often don’t have the time to dig into the research!
That’s why myths like “pain means damage” persist.
And that’s why treatments like PRP continue to focus on issues like “arthritis." Even if PRP injections show some limited short-term benefit, they are still focused on "damage" that is of highly questionable importance.
As you can see, the research on PRP injections for pain isn’t great. There are very few high quality studies demonstrating any positive benefit from PRP injections for soft-tissue issues.
There are no high quality studies that show long term positive benefit from PRP injections. And the studies that show some short-term benefit for things like knee arthritis are based on a set of beliefs that do not hold up under closer scrutiny.
Reframe the problem. Look at how you use your body closely. Train your body to move better and move well in a variety of ways.
This is how every coach at Upright Health has overcome their own pain issues. It’s how we coach our clients to overcome theirs.