title: Diagnostic features of sciatica without lumbar nerve root compression.
abstract: METHODS
  Retrospective case series review of patients showing sciatica without radiographic evidence of nerve root compression.
  
  
  OBJECTIVE
  To elucidate clinical features of sciatica caused by extralumbar spinal lesions.
  
  
  BACKGROUND
  Sciatica caused by extralumbar spinal lesions has been reported sporadically. Given the paucity of case series studies, however, the pathology and clinical features of such sciatica remain not fully understood.
  
  
  METHODS
  Sixty-one patients who presented with persistent sciatica were examined with lumbar magnetic resonance (MR) imaging. Of these, the records of patients showing no detectable nerve root compression in MR images were reviewed with respect to demographics, neurologic status, further diagnostic procedures, treatments, and treatment outcomes.
  
  
  RESULTS
  Of 61 patients, 10 (16.4%) showed sciatica and a lack of nerve root compression in the lumbar MR imaging. In demographics, there was female sex dominance (9 patients) and right side preference (9 patients). Eight patients exhibited sensory disturbance beyond a single dermatome. Piriformis syndrome was diagnosed in 3 patients and 5 patients were considered to have sacral plexus pathologies associated with gynecologic conditions such as ectopic endometriosis, ovarian cyst, and pregnancy. A review of the literature also supported the right side preference in sciatica associated with gynecologic conditions.
  
  
  CONCLUSIONS
  Piriformis syndrome and gynecologic conditions account for most cases of extralumbar spinal sciatica. Female sex, right side involvement, and overlapping sensory disturbance are suggestive of extralumbar spinal sciatica associated with gynecologic conditions.
authors.affiliation: Department of Orthopaedic Surgery, Sapporo Medical University School of Medicine, Chuo-ku, Sapporo, Japan. myoshimo@sapmed.ac.jp
authors.forename: Mitsunori
authors.initials: M
authors.lastname: Yoshimoto
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kawaguchi
authors.forename: Tsuneo
authors.initials: T
authors.lastname: Takebayashi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Isogai
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Kurata
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Nonaka
authors.forename: Gosuke
authors.initials: G
authors.lastname: Oki
authors.forename: Ima
authors.initials: I
authors.lastname: Kosukegawa
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Yamashita
mesh_terms: D000328:Adult; D002081:Buttocks / Q000294:innervation / Q000473:pathology / Q000503:physiopathology; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D005831:Genital Diseases, Female / Q000150:complications; D005836:Genitalia, Female / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D008159:Lumbar Vertebrae / Q000473:pathology / Q000503:physiopathology; D008160:Lumbosacral Plexus / Q000473:pathology* / Q000503:physiopathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology / Q000503:physiopathology; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012584:Sciatic Nerve / Q000473:pathology* / Q000503:physiopathology; D012585:Sciatica / Q000175:diagnosis* / Q000209:etiology* / Q000503:physiopathology; D012720:Severity of Illness Index; D012727:Sex Characteristics; D017678:Sex Distribution; D013126:Spinal Nerve Roots / Q000473:pathology / Q000503:physiopathology; D055815:Young Adult