Piriformis syndrome

Background

Piriformis muscle in relation to sciatic nerve.
  • The piriformis muscle acts as an external rotator, weak abductor, and weak flexor of the hip
  • It originates from the anterior sacrum and inserts on the greater trochanter of the femur
  • The sciatic nerve typically exits the greater sciatic foramen deep along the inferior surface of the piriformis muscle, but in approximately 20% of people, the sciatic nerve pierces the piriformis muscle [1]
  • Local inflammation of the piriformis can cause muscular compression or irritation of the sciatic nerve causing local or radicular pain

Clinical Features

  • Pain in area of buttocks and hamstring muscles
  • Worsened by sitting, climbing stairs, or squatting

Differential Diagnosis

Hip pain

Acute Trauma

Chronic/Atraumatic

Evaluation

  • May have palpable, tender mass over piriformis muscle
  • Consider when patient has classic signs of lumbar radiculopathy with negative provocative testing, normal neurologic exam
  • Provocative testing with Freiburgs test: placing hip in extension and internal rotation, and then resisting external rotation
    • Pain or sciatic symptoms yield a positive test
  • Consider XR or outpatient MRI to rule out other causes of gluteal and sacroiliac pain

Management

  • Conservative
    • Avoidance of contributory activity (e.g. running, cycling, heavy lifting)
    • Physical therapy
    • NSAIDs +/- gabapentin if patient has neuropathic pain
  • May benefit from referral for steroid or botulinum toxin injection [2]

Disposition

  • Outpatient

See Also

External Links

References

  1. Boyajian-O'Neill LA, McClain RL, Coleman MK, Thomas PP. Diagnosis and Management of Piriformis Syndrome: An Osteopathic Approach. J Am Osteopath Assoc 2008;108(11):657–664.
  2. Cass SP. Piriformis syndrome: a cause of nondiscogenic sciatica. Curr Sports Med Rep. 2015 Jan;14(1):41-4. doi: 10.1249/JSR.0000000000000110. PMID: 25574881.