Piriformis syndrome is an uncommon condition where your piriformis muscle puts pressure on your sciatic nerve. The hallmark symptom is shooting, aching, or burning pain in your buttocks and the back of your leg.
There are currently no universally accepted tests to diagnose piriformis syndrome. Many other conditions can cause nearly identical symptoms, and can easily be mistaken for piriformis syndrome.
Keep reading to learn why piriformis syndrome remains controversial, and which tests your healthcare provider is most likely to use to diagnose it.
Your piriformis is a small, flat muscle that attaches to your sacrum and the top of your femur. It’s one of a handful of small muscles that externally rotates your femur. It’s found beneath your gluteus maximus muscle and passes over your sciatic nerve.
Your sciatic nerve is the largest nerve in your body. It lets you move and feel many parts of your legs.
The sciatic nerve originates in your lower spinal cord at the level of your L4 to S3 vertebrae. Its branches reach the soles of your feet.
In theory, inflammation or hypertrophy (increased size) of your piriformis muscle could put pressure on your sciatic nerve and disrupt the nerve’s function.
Research on how to best diagnose piriformis syndrome remains ongoing.
There are currently
Healthcare professionals often make the diagnosis by examining your medical history and using a series of physical tests to rule out conditions like sciatica, a lumbar sprain, or a disc injury.
If your healthcare provider believes that piriformis syndrome could be the cause of your pain, they will likely palpitate your piriformis muscle to search for tenderness.
Your doctor may conduct physical tests to see if stretching or activating your piriformis muscles causes pain.
If they find your piriformis is tender to touch, and you report pain in your deep gluteal region in the following four tests, they may suspect piriformis syndrome.
FAIR is an acronym that stands for flexion, adduction, and internal rotation.
During the test, you’ll lie on your side with your injured leg on top. The tester will stabilize your hip with one hand and bring your knee toward your chest while moving it toward the midline of your body.
At the same time, they’ll rotate your lower leg away from the midline of your body to put your piriformis muscle under tension.
You’ll lie on your side with your affected leg on top and your knees bent. You’ll be told to raise your top thigh to see if the movement causes pain in your buttocks.
Pace maneuver test
You’ll sit with a 90-degree angle at your hips and knees. The tester will put their hands on the outer side of your lower legs, and you’ll be told to push into their hands.
You’ll lie on your back with your legs straight. The tester will take your femur and roll it inwardly. They’ll then ask you if you feel pain in your deep gluteal region.
Research has shown that patients thought to have piriformis syndrome had an enlarged piriformis and sciatic nerve on their injured side, compared to their asymptomatic side and to healthy volunteers. An ultrasound, therefore, can detect this.
However, more research is needed to back these findings.
Differences between piriformis syndrome and lumbar disc bulge testing
Both piriformis syndrome and a lower lumbar disc bulge are usually diagnosed by eliminating other possible causes of pain.
The straight leg test is commonly used to test for sciatica. If you have low back and/or leg pain when your leg is flexed to between 30 and 70 degrees, you may have sciatica caused by a bulging disc
Imaging techniques are unlikely to be used in the early stages of sciatica diagnosis. However, MRI may be used if the pain isn’t resolved from conservative treatment after
The symptoms of piriformis syndrome are similar to the symptoms of a lower lumbar disc bulge as well as many other conditions. The similarity of symptoms can make it difficult for your healthcare provider to locate the origin of the problem.
- numbness, or the feeling of pins and needles, down the back of your leg
- chronic pain around your hip and buttocks
- pain when getting out of bed
- an inability to sit for a prolonged period
- pain in the buttocks that gets worse when you move your hips
Piriformis syndrome still remains a controversial diagnosis among health professionals, and some researchers have questioned its existence entirely.
A number of
The idea that sciatic pain could be caused by piriformis syndrome was first described in scientific literature in
Since then, Robinson’s original diagnostic criteria have been disputed and refuted.
Research supporting piriformis syndrome
In a recent
However, more research is needed to better understand many aspects of the condition like how prevalent it is and how to best diagnose it.
Possible alternative explanations
Piriformis syndrome is described as a condition causing compression of your sciatic nerve. However, it has also been hypothesized that posterior leg pain could be caused by another independent nerve called the
Deep gluteal syndrome
It’s plausible that some diagnosed cases of piriformis syndrome are actually other types of deep gluteal syndrome caused by other muscles such as obturator internus, gemellus, or quadratus femoris.
Piriformis syndrome is a controversial diagnosis for pain in your buttocks and the back of your leg. Recent evidence suggests that piriformis syndrome is real. But it’s not clear how common it is, and there’s no universally accepted test for diagnosing it.
Usually, your healthcare provider will diagnosis piriformis syndrome by eliminating other possible conditions. Recent evidence suggests that ultrasound may have the potential to diagnose piriformis syndrome, but more research is needed.