title: Median nerve penetration by a persistent median artery and vein mimicking carpal tunnel syndrome.
abstract: BACKGROUND
  Carpal tunnel syndrome (CTS) is a common clinical syndrome seen in the outpatient setting that is easily confirmed by electrodiagnostic testing.
  
  
  METHODS
  We describe the case of a patient who presented with the classic symptoms and neurological examination for CTS, but had a normal nerve conduction study and electromyogram.
  
  
  RESULTS
  Neuromuscular ultrasound of the median nerve on the symptomatic side revealed penetration of the nerve by a persistent median artery and vein in the mid-forearm, with a positive sonographic Tinel sign over this spot. This finding is an anatomical variation that has been described sparingly in the literature, mostly in cadavers. It has not been reported previously to be a mimic of CTS.
  
  
  CONCLUSIONS
  This case demonstrates the diagnostic utility of neuromuscular ultrasound and the importance of considering an anatomical variation involving the median nerve in the differential diagnosis of CTS.
authors.affiliation: Department of Neurology, Warren Alpert Medical School of Brown University, Providence, Rhode island, USA.
authors.forename: Kara
authors.initials: K
authors.lastname: Stavros
authors.affiliation: Department of Radiology, Morristown Medical Center, Morristown, New Jersey, USA.
authors.forename: David
authors.initials: D
authors.lastname: Paik
authors.affiliation: Department of Neurology, Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue, Annenberg Second Floor, Box 1052, New York, New York, 10029, USA.
authors.forename: Rajeev
authors.initials: R
authors.lastname: Motiwala
authors.affiliation: Department of Neurology, Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue, Annenberg Second Floor, Box 1052, New York, New York, 10029, USA.
authors.forename: Jesse
authors.initials: J
authors.lastname: Weinberger
authors.affiliation: Department of Neurology, Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue, Annenberg Second Floor, Box 1052, New York, New York, 10029, USA.
authors.forename: Lan
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Department of Neurology, Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue, Annenberg Second Floor, Box 1052, New York, New York, 10029, USA.
authors.forename: Susan
authors.initials: S
authors.lastname: Shin
mesh_terms: D002349:Carpal Tunnel Syndrome / Q000503:physiopathology*; D004568:Electrodiagnosis; D004576:Electromyography; D006225:Hand / Q000294:innervation; D006801:Humans; D008297:Male; D008475:Median Nerve / Q000473:pathology*; D020423:Median Neuropathy / Q000150:complications / Q000175:diagnosis*; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology / Q000648:ultrastructure; D009431:Neural Conduction / Q000502:physiology; D010292:Paresthesia / Q000175:diagnosis* / Q000209:etiology; D014463:Ultrasonography
keywords: carpal tunnel syndrome; median nerve penetration; median neuropathy; neuromuscular ultrasound; persistent median artery