There is a Chinese proverb from Confucius that states, “Never use a cannon to kill a mosquito.” However, in medicine, there’s also another saying: “When all you have is a hammer, everything looks like a nail.” Where those two intersect is when doctors use overly invasive treatments to try to cure problems that can be easily treated less invasively because that’s what they’re used to doing. This morning’s example is a procedure called transcatheter arterial embolization used to treat tennis elbow. Let’s dig in.
For many patients, tennis elbow can be a real problem, leading to significant pain and loss of function. This is a problem whereby the muscles of the forearm that anchor at the outside of the elbow begin to get painful and swollen, and over time the tendons can develop small tears, leading to a condition known as tendinopathy. If you have the more severe versions of this problem, even opening a door or shaking a hand can be painful and difficult.
The traditional treatment for tennis elbow is injecting high-dose steroids, which has been shown to cause problems. Newer therapies such as platelet-rich plasma are highly effective and have solid research supporting their use. Hence, in the vast majority of patients, tennis elbow is very easy to treat with a very safe and minimally invasive injection of the patient’s own blood platelets.
Using a Cannon to Kill a Mosquito
Hyperspecialization in medicine is a two-edged sword. Why? The good news is that it creates experts in a specific subject matter who know a lot about certain medical problems. The bad news is that often those experts try to use what they know for treatment when another therapy that they don’t know much about would be far less risky and invasive for the patient. A great example of this issue is the stark contrast between what spinal surgeons often recommend, like highly invasive low-back fusions, versus what an expert physical therapist might recommend, which is a set of specific exercises. There is definitely crossover where there are patients who end up with ridiculously invasive spinal fusions that could have been treated with high-quality physical therapy and avoided surgery.
More recently I’ve been seeing interventional radiologists and cardiologists trying to address common musculoskeletal-pain problems, that can be easily treated with regenerative injections, by using much more invasive embolization procedures. This means that instead of a simple and low-risk injection of someone’s platelets, instead, the doctor floats a catheter into the blood supply for the painful area and then purposely blocks that blood supply (embolization) to reduce the blood flow to the painful part.
Transcatheter Arterial Embolization for Tennis Elbow
This new procedure, which is more like using a nuclear bomb to kill a mosquito, is called transcatheter arterial embolization (TAE). This means that to treat tennis elbow, an interventional radiologist or cardiologist floats a catheter into the blood supply for the painful elbow tendon and then kills off the arterial blood supply to the area. While I’m sure this kills the local nerves and makes it feel better, it’s likely not a real healthy thing to do to a tendon. The rationale for doing this? A recent study presented at a radiology conference showed decreased elbow pain and increased function when TAE was used.
So what would be the possible side effects of TAE versus just a local shot of PRP? TAE has as its side effects tearing the artery, blood clots, nerve damage, and other issues. Even calculating the large-scale side effects for TAE in this type of therapy is difficult, because the therapy is primarily used to treat tumors. Hence, the studies of its side effect profile refer to the treatment of cancer patients.
Why would someone use a much more invasive arterial catheterization to treat a common problem that can be treated much less invasively by a PRP shot? Money. The folks that make these TAE devices are looking to grow their device sales beyond the niche market of cancer care, and tennis elbow is a huge market. Add in the fact that an insurance company pays very little for a steroid shot at the elbow versus much more for an arterial embolization procedure, and from a financial standpoint, you have a winner. However, while the companies making the devices and the doctors get rich, the patients are exposed to much higher risks.
The upshot? In medicine, as a patient, you always have to be wary of the hammer and the nail phenomenon that leads to using a cannon to kill a mosquito. Just remember, you’re the mosquito in that equation!