Patients tend to believe their doctor, so when their doctor tells them their shoulder pain is due to a rotator cuff tear seen on MRI, most don’t question it. But maybe you should? More and more studies continue to show that shoulder MRI results often can’t predict why the patient hurts. So if we were to hypothesize that shoulder pain accompanied by a rotator cuff tear is always due to the tear, time and time again, our hypothesis would be disproven. It’s never a given that a rotator cuff tear causes pain; in fact, the studies we’ll cover in this article show that it is inaccurate to assume that a rotator cuff tear is causing your shoulder pain despite what’s seen on MRI.
Before we dive into the studies, let’s review rotator cuff tears and surgery.
What Is a Rotator Cuff Tear?
The rotator cuff is a complex series of muscles and tendons around the shoulder that help lift the arm and stabilize the ball in the socket (the shoulder joint). A tear is exactly what it sounds like—a tear in the tissue. While some rotator cuff tears result from trauma, the vast majority of rotator cuff tears happen from simple wear and tear as we age. The most common scenario for a tear to occur is simply a slightly more demanding movement than usual. How could that happen? It’s been known for a considerable amount of time that the rotator cuff doesn’t have the best blood supply, but blood supply varies to many areas of the body. The problem is likely a lack of healthy progenitor cells and stem cells to repair the damage as it occurs over time, and at some point with little provocation, the unhealthy tissue simply fails and a tear occurs.
What Is Rotator Cuff Tear Surgery?
A rotator cuff surgery involves cutting into the shoulder and stitching the rotator cuff tear back together. Recovery time can be lengthy, and as we have discussed in many articles before, there is a good amount of research showing that surgery is largely ineffective for many types of rotator cuff tears. And in larger tears of the rotator cuff, approximately 6 in 10 don’t heal properly, even with surgery. For patients over 60, shoulder surgery recovery is even more difficult, with 1 in 3 rotator cuff tears not healing in that age group. A good number of surgical patients never recover full range of motion following surgery and pain still persists. In addition, many studies show that shoulder pain prior to surgery has no correlation with the rotator cuff tear or the severity of the tear. So what’s causing the pain?
Study Shows Shoulder Pain Associated with Inflammation
A study performed in Japan last year analyzed joint fluid obtained from 38 patients before and after orthopedic rotator cuff surgery for various chemical messenger molecules (cytokines). Cytokines work for the immune system and call our immune cells into action when there is inflammation, infection, or some other trauma.
Imagine a station of firefighters. The firefighters are our immune cells, always there, ready and waiting. The firefighters might be cleaning the trucks, doing some training exercises, or stocking their equipment, but when that alarm sounds, they jump to action and race straight to the fire. The alarm is our cytokines, and when that alarm sounds, our immune cells jump to action and race straight to the inflammatory fire—they are our first responders.
Interestingly, but not surprising, the study concluded that larger rotator cuff tears were associated with less pain, and that more pain was accurately predicted by more IL-8 (interleukin 8) in the joint fluid. IL-8 is an inflammatory cytokine, an alarm sounding when inflammation is present. So the pain in this study was due to the inflammation, not the tear itself.
Studies Show Shoulder Pain Is Associated with Mental Health, Cormorbidities
Last month, another study concluded that the mental health of the patient was associated with pain (measured using the Short Form-36 Mental Component Summary) while the severity of a full-thickness rotator cuff tear generally had no association.
In 2014, this study also concluded that the severity of rotator cuff tears are not associated with shoulder pain and that “Factors associated with pain are comorbidities.”
This study stated that “the prevalence of full-thickness rotator cuff tears increases with age [and] many patients are asymptomatic and may not require surgical repair.” Even when there is pain present, the study concluded that physical therapy, rather than surgery, should be sufficient to address the symptoms in most cases.
Study Answers a Bigger Question: Does Rotator Cuff Tear Repair Fix My Pain?
Another study concluded a more disturbing result: Rotator cuff repair doesn’t fix pain or function in the shoulder. This should be an eye-opener for patients, whose primary purpose for undergoing a rotator cuff repair to begin with is typically due to pain. This makes sense given that so many studies are showing that shoulder pain is not due to the presence of a rotator cuff tear. If a surgeon “fixes” your rotator cuff tear to eliminate your pain, but your tear isn’t actually the source of your pain, why was it necessary to have the surgery?
The Common Factor
While these studies, and many, many more, show a variety of reasons for shoulder pain in the presence of a rotator cuff tear, there is one common factor: none link shoulder pain to the actual rotator cuff tear.
The Other Option
If the reason the rotator cuff fails in the first place is a lack of local stem cells, doesn’t it make sense that replacing those cells is critical to get the structure as healthy as possible?
What if for about 70–80% of rotator cuff tears you could avoid the surgery and have a much quicker recovery? That’s the procedure that we have pioneered over the last decade. Instead of surgery, you get an ultra-precise injection of your own stem cells under ultrasound guidance using a patented protocol.
A rotator cuff tear is one of the most commonly treated conditions across the Regenexx Network, and we consistently see good outcomes in these patients. Having said that, while most tears will heal with just a precise injection, there are a few massive rotator cuff tears that are unlikely to be helped without surgery. Keep in mind that even after surgery, stem cell injections may assist in the healing and improvement of tissue. As an example, one recent study showed that using stem cells after surgery reduced the retear rate by half.
The upshot? If your shoulder pain isn’t due to the rotator cuff tear your doctor finds on your MRI before surgery, it stands to reason your pain won’t subside after surgery. And given your pain, and your surgeons advice, is probably what is driving you toward the operating room in the first place, it seems in the majority of cases that this surgery may simply be futile. However, whether you’ve had surgery or not, Regenexx may be able to help you with your shoulder pain.