piriformis injection

Piriformis Injection: What Your Doctor Won’t Tell You

piriformis muscle

It’s hard for both physicians and patients alike to understand the intense complexity of the connected body. It’s easier to come up with a description for one part that hurts and call it good. I call this “parting it out,” and this is definitely the case with a piriformis injection. Even though there are likely other reasons the piriformis is a problem, our “easy fix” medical care system loves an easy-to-understand label.

The Traditional Piriformis Story

piriformis injectionThe piriformis is a muscle that goes from the front of the tailbone to the outside of the hip. See the image to the right. The sciatic nerve in some patients can go through the muscle; in most others, it exits in front of and below the muscle. The sciatic nerve is one of the major nerve bundles that’s made up of a collection of spinal nerves from the low back and supplies the muscles in the leg. When the sciatic nerve is irritated by the piriformis muscle, the foot or leg can go numb or the muscles it supplies can develop pain and problems. Other times patients just develop a “pain in the butt” where the piriformis nerve travels.

The Traditional Therapy Based on the Traditional Theory

piriformis injectionIf the piriformis muscle is tight and that’s causing pain in the muscle/tendon or irritating the nerve, then you need to stretch the muscle. Many different piriformis stretches have been described. To the right is the most common. You lie on your back and hook the foot on the side with the tight piriformis around the opposite knee and then pull that leg back, creating a stretch in the butt area.

A common piriformis injection therapy is steroid anti-inflammatories into the piriformis area, either blind or under ultrasound or fluoroscopic guidance. Finally, if none of that works, shockwave therapy may be tried. The idea here is to cause irritation in the muscle to try and kick off a healing response. Botox is another common piriformis injection concept. The idea here is that the Botox will temporarily relax the muscle. Finally, yet another piriformis injection strategy is platelet rich plasma (PRP). The idea here is that the growth factors in the PRP will help heal the damaged muscle and tendon.

If all else fails, some surgeons cut the muscle to try to free the nerve. This is a highly invasive treatment that obviously can have serious side effects. In addition, it destroys the normal biomechanics of the sacrum and SI joint.

However, none of these therapies answer a critical question. Why is the muscle tight in the first place? Let’s explore that idea.

What Does the Piriformis Muscle Do, and What Could Cause It to Be Tight?

Let’s first look at what we know from MRI research about the piriformis muscle. In one large MRI study, 86% of the patients had either an enlarged muscle or tendinopathy in the muscle tendon (tendon damage). Only about one in four patients had evidence that the sciatic nerve was involved. So what could make the muscle enlarged or beat up?

piriformis injectionWe’ve known since the ’90s that the piriformis muscle along with many ligaments are involved in stabilizing the sacroiliac (SI) joint. The SI joint lives between the tailbone and the back of the pelvis, so it makes sense that any muscle attached to the tailbone could have a role in stabilizing the joint. The joint is also stabilized by thick and extensive ligaments (see image to the left).

What would happen to the piriformis muscle if the SI joint ligaments were loose? It would go into overdrive to try and stabilize the sacrum (tailbone). This would explain why the piriformis is chronically tight, which in turn causes the muscle to get bigger and beat up.

What Nobody Has Ever Told You About Piriformis Syndrome

So if the cause of the big and torn-up piriformis muscle is an unstable SI joint, why would we treat the muscle? That’s like trying to fix a torn-up tire that got that way because the lug nuts on the rim were loose by focusing on the tire. That approach makes no common sense. In fact, it makes more sense to tighten the lug nuts first and then repair the tire.

So how do you tighten the lug nuts here? You can inject a number of substances to tighten the SI joint ligaments. This can be something as simple as prolotherapy or orthobiologics, like platelet rich plasma or bone marrow stem cells. These are precise fluoro- or ultrasound-guided injections directly into specific ligaments.

The upshot? Always ask yourself why is this happening? Regrettably, most of medicine is focused only on the symptoms and thus only understanding a small part of the whole disease. This happens every day with piriformis syndrome. So why is the piriformis tight? It’s usually instability in the sacrum where the muscle is attached. Hence, if you fix the instability and the muscle, you get a more permanent fix that doesn’t destroy the normal biomechanics.



*DISCLAIMER: Like all medical procedures, Regenexx® Procedures have a success and failure rate. Patient reviews and testimonials on this site should not be interpreted as a statement on the effectiveness of our treatments for anyone else.
Read 20 Comments
  1. WOW, finally a doctor that knows the biomechanics of the body and how to solve the problem!!! Are all of the doctors at Regenexx this knowledgeable?
    Thank you for this information.

  2. Is it likely that overuse of gluteal muscles as required for classical ballet could inflame the piriformis muscle (bigger and beat up)? I was diagnosed with piriformis syndrome with an EMG. As someone with 48 years of classical ballet training and teaching, I find that when I am stressed I engage the gluteal muscles, and then I experience the spasms of the piriformis syndrome.

    You are right. I have been treated for the symptoms, not the cause.

  3. How do you diagnose the instability at the SI joint ? None of the tests seem to be valid when scrutinized .

  4. Are there any stretches that will help alleviate this condition?
    And … is there anything you should NOT do that would make the condition worse?

    1. Patti,

      We’ve included the “Piriformis Stretch” in the blog. The thing to be avoided to not make the situation worse would be Surgery!

  5. My doc insists I do cortisol shots in hip to relieve pain but says I will need hip transplant once I’m bone on bone. Grrr doesn’t the cortisol shot do bad things to the bones so I won’t be able to have a hip transplant? I’m was a advice sports person now I’m a couch potato.. so sad.

  6. Is there a way to find a doctor that does the ultrasound guided piriformis shot near me. One that actually takes my insurance. I have been looking and can’t find a doctor who does this let alone takes my insurance. I live in northern Indiana. Any help would be appreciated.

    1. Kathleen,

      We don’t know of anyone doing this level of injection work that works with Insurance, but we’d be glad to help you locate the closest Regenexx Doctor that can help. Would you like our team to contact you?

    1. Robert,
      Sorry, we don’t execute prescriptions from other Doctors. We’d be glad to examine you, see what’s causing the issue with your Piriformis muscle, and treat that.

  7. I am looking for a recommendation for the closest Regenexx Doctor that can help me to examine and determine the cause and best treatment for a chronically tight, painful piriformis.

  8. Do you know of any Regenexx Drs who treat si ligament instability in NJ. I did a lookup any found a Dr. Kranberg but when I called his office I was told he doesn’t do SI ligaments. Please help.

Leave a Reply

Your email address will not be published. Required fields are marked *

More Questions? Search the Knowledge Base.

Share This