title: Awareness of the median sacral artery during lumbosacral spinal surgery: an anatomic cadaveric study of its relationship to the lumbosacral spine.
abstract: OBJECTIVE
  The purpose was to investigate the median sacral artery (MSA) anatomical pathway in terms of its relationship to the lumbosacral spine.
  
  
  METHODS
  The posterior wall and lumbosacral spine of 54 adult embalmed cadavers were dissected. The MSA emerging point was identified. The distance from its emerging point to the lateral border of the vertebral body was measured bilaterally. The pathway of the MSA from the emerging point to the sacral promontory was described together with the MSA length. All outcomes were independently measured by two observers. Statistics on obtained data were calculated.
  
  
  RESULTS
  Most of the MSA emerging points were at the L5 vertebral body (94.4 %). The emerging point from the right and left lateral border of the L5 vertebral body was 3.31 ± 0.54 cm and 2.39 ± 0.51 cm, respectively. The MSA then lay along the middle one-third of the anterior surface of the lumbosacral junction. The mean length between the emerging point and the sacral promontory was 2.73 ± 0.97 cm.
  
  
  CONCLUSIONS
  The MSA anatomy is important for prevention of intra-operative bleeding. For anterior lumbosacral surgery, the MSA should be identified and controlled before proceeding with the spinal surgery. For posterior bicortical sacral screw placement, the screw tip should be fluoroscopically checked to avoid inserting the screw tip into the mid sacral promontory. By first approaching the anterior sacral promontory, the surgeon will find the MSA within the middle one-third zone, and 2.47-2.99 cm cephalad to this, the iliac vessels. Knowledge of the MSA helps the surgeon to operate more safely.
authors.affiliation: Department of Orthopaedics, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand. sursea@kku.ac.th.
authors.forename: Surachai
authors.initials: S
authors.lastname: Sae-Jung
authors.affiliation: Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Kimaporn
authors.initials: K
authors.lastname: Khamanarong
authors.affiliation: Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Worawut
authors.initials: W
authors.lastname: Woraputtaporn
authors.affiliation: Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Pattama
authors.initials: P
authors.lastname: Amarttayakong
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001012:Aorta, Abdominal / Q000033:anatomy & histology*; D002102:Cadaver; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000601:surgery*; D008161:Lumbosacral Region / Q000601:surgery; D008297:Male; D008875:Middle Aged; D010388:Pelvis / Q000601:surgery; D012447:Sacrum / Q000098:blood supply* / Q000601:surgery
keywords: Common iliac vessels; Lumbosacral spine; Median sacral artery; Middle sacral artery