[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Conditions](https://durgical.com/en/conditions/) › Piriformis syndrome [Conditions](https://durgical.com/en/conditions/) · [Lower limb](https://durgical.com/en/anatomy/region/lower-limb/) # Piriformis syndrome Piriformis syndrome is buttock pain, often spreading down the thigh, blamed on the piriformis muscle irritating the sciatic nerve; it is debated. Updated 2026-10-29 ## Structures involved Tap one to see what it is and open it in 3D. - [Piriformis](https://durgical.com/en/anatomy/piriformis-muscle/) - [Sciatic nerve](https://durgical.com/en/anatomy/sciatic-nerve/) - [Gluteus maximus](https://durgical.com/en/anatomy/gluteus-maximus-muscle/) - [Sacrum](https://durgical.com/en/anatomy/sacrum/) - [Hip bone](https://durgical.com/en/anatomy/hip-bone/) - [Superior gemellus](https://durgical.com/en/anatomy/superior-gemellus-muscle/) - [Obturator internus](https://durgical.com/en/anatomy/obturator-internus/) - [Posterior femoral cutaneous nerve](https://durgical.com/en/anatomy/posterior-femoral-cutaneous-nerve/) - [Piriformis fascia](https://durgical.com/en/anatomy/piriformis-fascia/) ## What it is Buttock pain, often spreading down the back of the thigh, attributed to irritation or compression of the sciatic nerve by the piriformis muscle. It is a diagnosis of exclusion and its existence and criteria are debated. ## Who gets it Its true frequency is unknown because no test confirms it; it is reported more often in women and in middle-aged adults, and it is now often grouped under deep gluteal syndrome. ## Causes - Direct trauma or a fall onto the buttock - Muscle hypertrophy, spasm or overuse - Anatomical variants in which the sciatic nerve or part of it passes through or above the piriformis - Prolonged sitting on hard surfaces or on a wallet in the back pocket - Scarring after hip surgery ## Risk factors - Prolonged sitting - Running or sports with repeated hip rotation - Buttock trauma - Leg length difference or altered gait ## Pathophysiology The sciatic nerve leaves the [pelvis](https://durgical.com/en/anatomy/region/pelvis/) through the greater sciatic foramen, usually just below the piriformis. Spasm, swelling, scarring or a variant course can compress or stretch the nerve at this point, causing pain and sometimes sensory change along the sciatic distribution. ## Classification - Primary: from anatomical variants of the muscle or nerve - Secondary: from trauma, mass, scarring or other causes - Considered one cause within deep gluteal syndrome ## Symptoms and signs - Deep buttock pain, often one-sided - Pain spreading down the back of the thigh, usually not below the knee - Worse with sitting, climbing stairs or hip rotation - Tenderness over the piriformis near the sciatic notch ## Red flags - Saddle numbness, urinary retention or incontinence (suspect [cauda equina](https://durgical.com/en/anatomy/cauda-equina/) syndrome) - Progressive weakness or foot drop - Fever, weight loss, cancer history or night pain ## Diagnosis **Clinical** Tenderness at the [piriformis](https://durgical.com/en/anatomy/piriformis-muscle/) and provocation tests that stretch or contract the muscle: FAIR (flexion, adduction, internal rotation), Freiberg, Pace and Beatty tests. No test is diagnostic alone. **Tests** Nerve conduction studies and EMG mainly exclude radiculopathy; an image-guided injection of local anesthetic into the muscle that relieves pain supports the diagnosis. **Imaging** Lumbar and pelvic MRI exclude disc herniation, stenosis, sacroiliac disease or masses; MR neurography can show the nerve and anatomical variants. ## Differential diagnosis - Lumbar disc herniation with radiculopathy - Lumbar spinal stenosis - [Sacroiliac joint](https://durgical.com/en/anatomy/sacroiliac-joint/) pain - Greater trochanteric pain syndrome - Proximal hamstring tendinopathy - Pelvic mass or vascular lesion ## Goal of treatment Relieve pressure on the sciatic nerve and buttock pain, and restore normal sitting and activity, after other causes have been ruled out. ## Treatment **Rehabilitation** Physiotherapy with piriformis stretching, hip strengthening and gait correction; this is the main treatment. **Medical** NSAIDs, muscle relaxants and neuropathic pain agents. **Procedure** Image-guided injection of local anesthetic with or without corticosteroid into the piriformis; botulinum toxin in refractory cases. **Surgical** Release of the [piriformis tendon](https://durgical.com/en/anatomy/tendon-of-piriformis/) and freeing of the [sciatic nerve](https://durgical.com/en/anatomy/sciatic-nerve/) in selected patients who fail other treatments. **Lifestyle** Avoiding long sitting on hard surfaces or with a wallet in the back pocket. ## Complications - Chronic buttock and leg pain - Missed alternative diagnosis, such as radiculopathy or a mass - Nerve injury from injection or surgery ## Prognosis Most patients improve with physiotherapy and, when needed, injections. Surgery is uncommon. ## Test yourself Think of the answer, then tap the question to see it. ## Which nerve is compressed in piriformis syndrome? The sciatic nerve, as it leaves the pelvis below or through the piriformis. ## Why is piriformis syndrome called a diagnosis of exclusion? No test confirms it, so lumbar radiculopathy, stenosis, sacroiliac and hip causes must be ruled out first. ## What does the FAIR test involve? Hip Flexion, Adduction and Internal Rotation, which stretch the piriformis and reproduce buttock pain. ## Which anatomical variant predisposes to piriformis syndrome? The sciatic nerve, or one of its divisions, passing through or above the piriformis. ## Which red flags point away from piriformis syndrome? Saddle numbness, bladder or bowel problems, progressive weakness or systemic signs such as fever or weight loss. [Add to my cards (5)](https://durgical.app/estudiar/?add=/en/conditions/piriformis-syndrome/) ## Related conditions - [Sciatica (Lumbar Radiculopathy)](https://durgical.com/en/conditions/sciatica/) - [Lumbar Disc Herniation](https://durgical.com/en/conditions/lumbar-disc-herniation/) - [Lumbar spinal stenosis](https://durgical.com/en/conditions/lumbar-spinal-stenosis/) - [Greater Trochanteric Pain Syndrome](https://durgical.com/en/conditions/greater-trochanteric-pain-syndrome/) - [Hamstring Strain](https://durgical.com/en/conditions/hamstring-strain/) - [Sacroiliac joint pain](https://durgical.com/en/conditions/sacroiliac-joint-pain/) Educational information, not medical advice. For any symptom, see a health professional. Sources: [Piriformis Syndrome](https://www.ncbi.nlm.nih.gov/books/NBK448172/) (StatPearls (NCBI Bookshelf), 2023). [← All conditions](https://durgical.com/en/conditions/) ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/conditions/piriformis-syndrome/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/conditions/piriformis-syndrome/