II. Definitions

  1. Piriformis Syndrome
    1. Sciatic nerve impingement by the piriformis Muscle (subset of Deep Gluteal Syndrome)

III. Causes

  1. Anatomic variant (sciatic nerve passes through piriformis Muscle in 15% of patients)
  2. Decreased core Muscle Strength (buttocks)
  3. Sacroiliac Joint Dysfunction
  4. Local Trauma to piriformis Muscle
  5. Pressure from wallet in pocket

IV. Symptoms

  1. Posterior Hip Pain and buttock pain
  2. Pain worse with sitting
  3. Sciatica
    1. Burning pain radiating down posterior leg

V. Signs

  1. Pain on Internal rotation of hip against resistance
  2. Seated piriformis stretch may exacerbate pain

VI. Diagnostics

  1. Consider MRI or electrodiagnostic nerve testing to identify entrapment location in refractory cases

VII. Management

  1. Local measures (e.g. ice or heat)
  2. NSAIDs
  3. Core Muscle Strengthening Exercises
  4. Correct comorbid conditions (e.g. Sacroiliac Joint Dysfunction)
  5. Local Corticosteroid Injection

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Ontology: Piriformis Muscle Syndrome (C0458224)

Definition (MSH) A chronic PELVIC PAIN characterized by pain deep in the buttock that may radiate to posterior aspects of the leg. It is caused by the piriformis muscle compressing or irritating the SCIATIC NERVE due to trauma, hypertrophy, inflammation or anatomic variations.
Definition (NCI) A condition referring to irritation or compression of the proximal sciatic nerve, secondary to contraction of the piriformis muscle. It results in pain in the hip or the back of the leg mimicking disk-related sciatica.
Definition (AOT) Spasm of the piriformis muscle causing sciatic pain.
Concepts Disease or Syndrome (T047)
MSH D055958
SnomedCT 129179000
Italian Sindrome piriforme, Sindrome del pitiforme
Japanese リジョウキンショウコウグン, 梨状筋症候群
English Sciatica due to compression of sciatic nerve at pelvic outlet, piriformis syndrome (diagnosis), piriformis syndrome, Piriformis Muscle Syndrome, Muscle Syndromes, Piriformis, Muscle Syndrome, Piriformis, Piriformis syndromes, Piriformis Muscle Syndromes, Piriformis syndrome, Syndromes, Piriformis Muscle, syndromes, Piriformis, Syndrome, Piriformis Muscle, syndrome, Piriformis, Piriformis Muscle Syndrome [Disease/Finding], piriformis syndromes, syndrome piriformis, Piriformis Syndrome, Pelvic outlet syndrome, Piriformis syndrome (disorder)
Czech Syndrom foramen piriforme, syndrom musculus piriformis
French Syndrome du muscle piriforme, Syndrome piriforme, Syndrome du (muscle) piriforme
German Piriformis-Syndrom
Portuguese Síndrome do Músculo Piriforme, Síndrome piriforme
Spanish Síndrome del Músculo Piriforme, ciática por compresión del nervio ciático en el estrecho inferior de la pelvis (trastorno), ciática por compresión del nervio ciático en el estrecho inferior de la pelvis, síndrome del estrecho inferior de la pelvis, síndrome piriforme (trastorno), síndrome piriforme, Síndrome del piriforme
Swedish Piriformis-syndromet
Polish Zespół mięśnia gruszkowatego
Hungarian Piriformis syndroma
Norwegian Piriformissyndromet
Dutch piriformis syndroom