How to Tell if Your Sciatica is Actually Piriformis Syndrome

When Your Sciatica Just Won’t Quit You Might Have a Misdiagnosed Case of Piriformis Syndrome

Peer Reviewed

If you’re struggling with a chronic pain in the butt, relief can be hard to find—especially if you have piriformis syndrome. The hallmark sign is hip and/or buttock pain on one side of the body along with low back pain that radiates down one or both legs.

Piriformis syndrome sciaticaPiriformis syndrome can be a real pain in the butt.

The problem is, piriformis syndrome is often mistaken for sciatica. While both conditions interfere with sciatic nerve function, sciatica results from spinal dysfunction such as a herniated disc or spinal stenosis. Piriformis syndrome, on the other hand, occurs when the piriformis muscle, located deep in the buttock, compresses the sciatic nerve.

Your medical provider’s solid understanding of the structure and function of the sciatic nerve and its relationship to the piriformis muscle is key to distinguishing between true or discogenic sciatica and piriformis syndrome.

What Is the Sciatic Nerve? 

The sciatic nerve originates near the base of the spine, where nerve roots at the L4, L5, S1, S2, and S3 vertebrae exit the bony opening of the spine and join into a single, large nerve and exits a bony arch called the sciatic notch. The sciatic nerve travels through the pelvis, passing under the front surface of the piriformis muscle as it travels through the pelvis.

It then cuts into two branches before going down each leg, branching out at the back of the knee to divide into the tibial and peroneal nerves, both of which supply the lower leg and foot. The sural nerves branch off from the tibial and peroneal nerves, terminating in the foot.

The sciatic nerve is responsible for bending the knee, bringing the thighs together (adduction), and flexing and extending the ankles and toes. It also provides sensation to the back of the thigh, the entire lower leg, the ankle, and the sole of the foot.

Piriformis? What’s That?

 

Piriformis sciatic nerve illustrationVisualizing the piriformis muscle and the sciatic nerve

The piriformis muscle originates at the front of the sacrum near the sacroiliac joint capsule and attaches to a bony knob on the femur (thigh bone) at the outermost part of the hip.

The piriformis helps externally rotate and abduct the hip, fancy words for turning your hip outward and bringing your thigh outward to one side while your hip is bent, such as when raising your knee and bringing your leg out when getting out of a car seat. It also offers stability while walking, running and standing.

Usually, the sciatic nerve passes directly underneath the piriformis before continuing down the back of the thigh. But for some, the sciatic nerve passes directly through the piriformis predisposing such people to piriformis syndrome, which may also be referred to as piriformis sciatica (as opposed to true, or discogenic, sciatica).

Piriformis Syndrome Symptoms

While piriformis syndrome doesn’t always present exactly the same way, common symptoms include pain in the buttocks that’s worse when sitting, especially with the legs crossed in a figure of four position. Maintaining that position for long periods can cause pain that radiates down one leg. Other symptoms may include:

  • Pain in the opposite sacroiliac joint
  • Pain with sitting standing or walking for more than 20 minutes
  • Intense pain with sitting or squatting
  • Pain and/or paresthesia (pins and needles, numbness, burning, tingling, or itching sensations) radiating from the sacrum down the back of the thigh, usually stopping above the knee
  • Pain that improves with movement
  • Pain when standing up from seated or squatting
  • Foot numbness

That’s why it’s so easy to mistake piriformis syndrome for sciatica; they have many of the same symptoms.

Causes of Piriformis Syndrome

Your anatomy may be behind your piriformis syndrome. This is known as primary piriformis syndrome and occurs when you have a split piriformis muscle, split sciatic nerve, and/or an atypical sciatic nerve path.

Secondary piriformis syndrome is far more common and is caused inflammation of soft tissues, muscle spasm or both, resulting in nerve compression. Direct trauma to the buttock can lead to inflammation, scarring and contractures of the piriformis muscle

This might be the result of a major event like a car accident or a fall. However, the most common cause is likely the gradual tightening of the piriformis muscle due to poor muscle fitness. Activities, such as long distance running or prolonged standing without proper stretching and strengthening of piriformis muscle is a common scenario in patients with piriformis syndrome . 

Testing for Piriformis Syndrome

Because piriformis syndrome symptoms mimic those of sciatica, your medical provider will perform specific tests to determine whether your symptoms are discogenic or caused by an impingement of the sciatic nerve by the piriformis muscle.

Your provider should examine your low back, hip, pelvis and sacroiliac joint and check your gait, posture and leg length. They’ll also test your reflexes, which should be normal if you have piriformis syndrome.

 

Piriformis syndrome sciatica physical therapyYour provider will manipulate your leg to check for piriformis syndrome.

Other signs of piriformis syndrome include:

  • Pain or tenderness when the doctor manipulates your piriformis
  • Tenderness to touch around your sacroiliac joint, greater sciatic notch, and piriformis that may radiate to your knee.
  • A positive La Seque sign. This means you feel localized pain when pressure is applied to your piriformis muscle and its tendon, especially while flexing your hip at a 90 degree angle and extending (straightening) your knee.
  • A positive Freiberg sign. This means you feel pain around the piriformis or reproduction of symptoms in response to putting your hip in extension and internal rotation while externally rotating against resistance.
  • A positive Pace’s sign. You’ll experience pain and/or weakness in response to resisting abduction and external rotation of the hip while you’re seated.
  • Pain in response to the FAIR test. FAIR stands for flexion, adduction, and internal rotation. This test requires you to lie on your asymptomatic side and relax while your provider guides your painful leg into hip flexion, turns it in toward your body, and then gently turns your lower leg outward.
  • A positive Beatty sign. This means you experience pain when, while lying on the asymptomatic side, your provider elevates your flexed symptomatic leg.

When testing for pain or weakness in specific positions, your provider will conduct each test until you experience symptoms or for up to 60 seconds, whichever comes first.

In addition to a physical exam, you might also need imaging to rule out other causes for your symptoms. Your doctor may order X-rays, an MRI, or a CT scan. In addition, injections into the piriformis muscle may be used to confirm the diagnosis, while simultaneously helping with treatment.

Once you pin down the source of your pain, you can move forward with treatment, which typically consists of NSAIDs (nonsteroidal anti-inflammatory drugs) and physical therapy. Although you might be inclined to rest, wait, and see what happens, the sooner you find the root of your issues, the sooner you can get back to pain-free living.

Piriformis syndrome or sciatica? Get a proper diagnosis; find a spine specialist near you who can help.

 

Updated on: 06/10/20
Continue Reading
6 Leading Causes of Sciatica and Sciatic Nerve Pain
Choll W. Kim, MD, PhD
×
SHOW MAIN MENU
SHOW SUB MENU
Cancel
Delete
Continue Reading:

6 Leading Causes of Sciatica and Sciatic Nerve Pain

Sciatica, also called lumbar radiculopathy, is mild to intense pain that radiates from the low back into the left or right leg. Sciatic nerve pain symptoms include numbness, tingling sensations, and weakness.
Read More