🦵 Piriformis Syndrome vs True Sciatica Simulator

Buttock Pain — Where Two Very Different Diagnoses Overlap

Placeholder: buttock and posterior leg pain can arise from muscle or spine sources.

• ~40%: Sciatica prevalence (placeholder lifetime risk)
• 6–8%: Piriformis syndrome share (placeholder of sciatica cases)
• 30–50y: Typical age (placeholder range)
• ~6:1: Female predominance (placeholder ratio)

Overlapping symptom pattern

Placeholder short note: both conditions mimic each other closely on history alone.

Piriformis Compression Site — Outside the Spinal Canal

Placeholder: sciatic nerve passes beneath or through piriformis in the deep buttock.

• ~17%: Nerve-muscle variant (placeholder anatomic split)
• Subgluteal: Compression site (placeholder location)
• Sitting/trauma: Onset trigger (placeholder cause)
• None: Spine involvement (placeholder — extraspinal)

Anatomic compression mechanism

Placeholder short note: muscle spasm or hypertrophy narrows the subgluteal space.

FAIR Test — Flexion, Adduction, Internal Rotation Provocation

Placeholder: hip FAIR positioning stretches piriformis over the nerve.

• ~88%: FAIR sensitivity (placeholder reported value)
• ~83%: FAIR specificity (placeholder reported value)
• 30–60s: Position hold (placeholder duration)
• Buttock pain: Positive sign (placeholder reproduction)

Provocative maneuver logic

Placeholder short note: pain reproduction implicates the piriformis, not the spine.

MRI Findings — Muscle Asymmetry vs Disc Herniation

Placeholder: MRI differentiates piriformis edema from nerve root compression.

• Asymmetry: Piriformis MRI sign (placeholder finding)
• Herniation: Disc MRI sign (placeholder finding)
• High: MRN utility (placeholder for nerve mapping)
• ~35%: Normal MRI cases (placeholder piriformis subset)

Imaging differentiators

Placeholder short note: spine MRI can be normal despite real piriformis pathology.

Discogenic vs Extraspinal — Reaching the Differential

Placeholder: combine exam, FAIR test, and MRI for final diagnosis and treatment.

• Conservative: Piriformis treatment (placeholder first-line)
• ESI/surgery: Disc treatment (placeholder options)
• Notable: Misdiagnosis rate (placeholder clinical issue)
• Possible: Double-crush cases (placeholder overlap)

Putting it together

Placeholder short note: concordant findings raise diagnostic confidence.

Treatment implication

Placeholder short note: therapy target follows the dominant compression site.

Placeholder key insight: FAIR-positive plus normal spine MRI favors piriformis syndrome.