title: MR imaging of entrapment neuropathies of the lower extremity. Part 1. The pelvis and hip.
abstract: Entrapment neuropathies can manifest with confusing clinical features and therefore are often underrecognized and underdiagnosed at clinical examination. Historically, electrophysiologic evaluation has been considered the mainstay of diagnosis. Today, cross-sectional imaging, particularly magnetic resonance (MR) imaging and specifically MR neurography, plays an increasingly important role in the work-up of entrapment neuropathies. MR imaging is a noninvasive operator-independent technique that allows identification of the underlying cause of injury, differentiation between surgically treatable and untreatable causes, and guidance of selective diagnostic anesthetic nerve blocks. Pathologic conditions affecting the lumbosacral plexus and major motor and mixed nerves of the pelvis and hip include neuropathies of the lumbosacral plexus, femoral nerve, lateral femoral cutaneous nerve, obturator nerve, and sciatic nerve; piriformis muscle syndrome; and injury of the gluteal nerves. Diagnosis of entrapment neuropathies of the pelvis and hip with MR imaging requires familiarity with the normal MR imaging anatomy and awareness of the anatomic and pathologic factors that put peripheral nerves at risk for injury.
authors.affiliation: Department of Radiology, New York University Hospital for Joint Diseases, 301 E 17th St, New York, NY 10003, USA. Catherine.Petchprapa@nyumc.org
authors.forename: Catherine N
authors.initials: CN
authors.lastname: Petchprapa
authors.forename: Zehava Sadka
authors.initials: ZS
authors.lastname: Rosenberg
authors.forename: Luca Maria
authors.initials: LM
authors.lastname: Sconfienza
authors.forename: Conrado Furtado A
authors.initials: CF
authors.lastname: Cavalcanti
authors.forename: Renata La Rocca
authors.initials: RL
authors.lastname: Vieira
authors.forename: Jonathan S
authors.initials: JS
authors.lastname: Zember
mesh_terms: D006615:Hip / Q000294:innervation* / Q000473:pathology*; D006801:Humans; D035002:Lower Extremity / Q000294:innervation* / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009408:Nerve Compression Syndromes / Q000175:diagnosis*; D010388:Pelvis / Q000294:innervation* / Q000473:pathology*