title: Risk Management for Avoidance of Major Vascular Injury due to Lateral Transpsoas Approach.
abstract: METHODS
  A retrospective study using 323 contrast-enhanced, multi-planner three-dimensional computed (3D-CT) scans.
  
  
  OBJECTIVE
  The aim of this study was to identify risk factors for injury to the major vessels in the lateral transpsoas approach.
  
  
  BACKGROUND
  To avoid critical complications such as major vessel injury, it is essential to examine anatomical information related to preoperative risk management that is specific to the lateral transpsoas approach.
  
  
  METHODS
  The abdominal contrast-enhanced, multi-planner 3D-CT scans of 323 consecutive subjects (203 males and 120 females, 15-89 years old) were retrospectively reviewed. The true axial views were used for evaluation of the locations of the major vein and artery at L3 to L4 and L4 to L5. According to the Moro system, the axial view was divided into 6 zones from the front side (A, I II, III, IV, P) and the locations of the dorsal tangential line of the major vessels were evaluated.
  
  
  RESULTS
  At the L3 to L4 level, the dorsal tangential line of the major vein located in zone A was found in 18% of subjects, in zone I in 74%, and in zone II in 8%. The line of the major artery was located in zone A in 92.6% of subjects and in zone I in 7.1%. At the L4 to L5 level, the line of the major vein was located in zone A in 5% of subjects, in zone I in 75%, in zone II in 20%, and in zone III in only 1 subject. The line of the major artery was identified in zone A in 87% of subjects, in zone I in 12%, and in zone II in 1%. Women had significant dorsal-migrated veins and arteries at both spinal levels (P < 0.01).
  
  
  CONCLUSIONS
  To avoid critical complications in extreme lateral lumbar interbody fusion, careful preoperative radiological evaluation of the major vessels and intraoperative care are important.
  
  
  METHODS
  3.
authors.affiliation: Department of Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan.
authors.forename: Toshinori
authors.initials: T
authors.lastname: Sakai
authors.forename: Fumitake
authors.initials: F
authors.lastname: Tezuka
authors.forename: Kazuma
authors.initials: K
authors.lastname: Wada
authors.forename: Mitsunobu
authors.initials: M
authors.lastname: Abe
authors.forename: Kazuta
authors.initials: K
authors.lastname: Yamashita
authors.forename: Yoichiro
authors.initials: Y
authors.lastname: Takata
authors.forename: Kosaku
authors.initials: K
authors.lastname: Higashino
authors.forename: Koichi
authors.initials: K
authors.lastname: Sairyo
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D016658:Psoas Muscles / Q000601:surgery*; D012189:Retrospective Studies; D012308:Risk Management / Q000379:methods*; D013123:Spinal Fusion / Q000009:adverse effects / Q000379:methods*; D014057:Tomography, X-Ray Computed; D057772:Vascular System Injuries / Q000000981:diagnostic imaging / Q000209:etiology / Q000517:prevention & control*; D055815:Young Adult