title: Laterality of cervical disc herniation.
abstract: OBJECTIVE
  Cervical disc herniation (CDH) is found more frequently at the lower cervical spine than at the upper or middle level. However, there is scarcity of data about the laterality of CDH. The aim of this study is to detect the laterality of CDH.
  
  
  METHODS
  We retrospectively evaluated preoperative computed tomography myelograms and magnetic resonance images of 75 cases of CDH who underwent single level anterior cervical discectomy and fusion at C4-5, C5-6, or C6-7 levels from 2008 to 2010 in our institute. Statistical analyses were performed using the Chi-square test.
  
  
  RESULTS
  Eleven cases were found at C4-5 level, 42 cases at C5-6 level, and 22 cases at C6-7 level. At C4-5 level, CDH was recognized at the right side in 2 cases, at the left side in 2 cases, and at the center in 7 cases. At C5-6 level, CDH was found at the right side in 20 cases and at the left side in 22 cases. At C6-7 level, CDH was found at the right side in 3 cases and at the left side in 19 cases with significantly high frequency of left-sided CDH (p < 0.025).
  
  
  CONCLUSIONS
  In this study, it was revealed that the left-sided CDH was more frequent than the right-sided CDH at C6-7 level.
authors.affiliation: Department of Spine and Spinal Surgery, Shinkomonji Hospital, 2-5, Dairishinmachi, Moji, Kitakyushu, Fukuoka 800-0057, Japan. yuichi5356@yahoo.co.jp
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Takao
authors.initials: T
authors.lastname: Yasuhara
authors.forename: Shinji
authors.initials: S
authors.lastname: Kumamoto
authors.forename: Kotaro
authors.initials: K
authors.lastname: Yoneda
authors.forename: Takashi
authors.initials: T
authors.lastname: Tanoue
authors.forename: Masayuki
authors.initials: M
authors.lastname: Nakahara
authors.forename: Takafumi
authors.initials: T
authors.lastname: Inoue
authors.forename: Yasukazu
authors.initials: Y
authors.lastname: Hijikata
authors.forename: Tejin
authors.initials: T
authors.lastname: Lee
authors.forename: Cesario V
authors.initials: CV
authors.lastname: Borlongan
authors.forename: Koichi
authors.initials: K
authors.lastname: Ogawa
authors.forename: Kenki
authors.initials: K
authors.lastname: Nishida
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002574:Cervical Vertebrae / Q000473:pathology*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000473:pathology*; D008297:Male; D008875:Middle Aged