title: Changes in abdominal vascular tension associated with various leg positions in the anterior lumbar approach: cadaver study.
abstract: METHODS
  A descriptive cadaveric study measuring arterial tension.
  
  
  OBJECTIVE
  Anterior lumbar surgery is technically challenging due to perioperative vascular complications. Many studies suggest approaches based on the anatomy of the abdominal vessel for safe vascular mobilization. However, the tension in the vascular structure is also important for adequate exposure of the target lesion. It has been established that the tension in the lumbar nerve at the root level can be changed by a straight leg raise test and that the structure of the vascular connection is similar to that of the neural connection. Consequently, a change in leg position could affect the tension of lumbosacral vessels. The purpose of this study was to evaluate the effect of leg position on the tension of lumbosacral vessels.
  
  
  METHODS
  We dissected 10 unembalmed cadavers using the method described by Gumbs et al, using the Synframe system to expose the abdominal artery and vein. The left iliac artery and the distal abdominal aorta were retracted to the right side at the L4-L5 disc level by a measuring retractor to which a strain gauge was attached. The tension was checked at various angles of the hip joint and the motions of the abdominal arteries were monitored in 4 unembalmed cadavers using a C-arm fluoroscope.
  
  
  RESULTS
  The tension in the abdominal aorta at L4-L5 level was decreased by 2.9% to 21.8% in the hip-flexion position, and the motion of the arteries showed proximal displacement of the external iliac artery and the common iliac artery during the hip-flexed position and veins also showed the same pattern of displacement as artery.
  
  
  CONCLUSIONS
  The results of this study would be useful for not only spinal surgery but also other vascular surgeries, particularly, in cases where patients with conditions such as atherosclerosis or stenosis.
authors.affiliation: Department of Neurosurgery, Kangdong Sacred Heart Hospital, Hallym University College of Medicine, Seoul, Korea.
authors.forename: Moon-Kyu
authors.initials: MK
authors.lastname: Kim
authors.forename: Dai-Soon
authors.initials: DS
authors.lastname: Kwak
authors.forename: Sin-Soo
authors.initials: SS
authors.lastname: Jeun
authors.forename: Chun-Kun
authors.initials: CK
authors.lastname: Park
authors.forename: Sae-Moon
authors.initials: SM
authors.lastname: Oh
authors.forename: Sang-Won
authors.initials: SW
authors.lastname: Lee
authors.forename: Seung-Ho
authors.initials: SH
authors.lastname: Han
mesh_terms: D034841:Abdominal Cavity / Q000033:anatomy & histology / Q000601:surgery; D000328:Adult; D000368:Aged; D001012:Aorta, Abdominal / Q000033:anatomy & histology / Q000502:physiology* / Q000601:surgery; D001696:Biomechanical Phenomena / Q000502:physiology; D002102:Cadaver; D005260:Female; D006615:Hip / Q000033:anatomy & histology / Q000502:physiology; D006621:Hip Joint / Q000033:anatomy & histology / Q000502:physiology; D006801:Humans; D007083:Iliac Artery / Q000033:anatomy & histology / Q000502:physiology* / Q000601:surgery; D007866:Leg / Q000033:anatomy & histology / Q000502:physiology*; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D008953:Models, Anatomic; D019635:Neurosurgical Procedures / Q000379:methods / Q000592:standards; D056888:Patient Positioning / Q000009:adverse effects / Q000379:methods* / Q000592:standards; D011187:Posture / Q000502:physiology; D016059:Range of Motion, Articular / Q000502:physiology*; D013314:Stress, Mechanical; D013718:Tensile Strength / Q000502:physiology