Surgical View of the Lumbar Arteries and Their Branches: An Anatomical Study

BACKGROUND: Although injury to the lumbar arteries during anterior spinal approaches is often encountered, there are few published articles regarding the relationship between the lumbar arteries and spinal cord ischemia. OBJECTIVE: To examine the morphology of the lumbar arteries and to emphasize their clinical importance. METHODS: With the aid of a surgical microscope, 80 lumbar arteries in 10 formalin-fixed male cadavers were studied. Measurements of these structures were made and relationships observed. RESULTS: The spinal artery was usually the first branch of the lumbar artery. The greatest lumbar artery diameter was at L4 and had a mean diameter of 3.25 mm; the smallest diameter was identified at L2 and had a mean diameter of 2.05 mm. The largest spinal artery diameter was at L3 (mean, 0.56 mm) and the smallest at L1 (mean, 0.42 mm). The largest anastomotic artery diameter was at L4 (mean, 0.42 mm) and the smallest at L1 (mean, 0.32 mm). For the right and left sides, the mean greatest distance between the origin of the lumbar artery and the tendinous arch was at L4 (mean, 40.9 and 31.8 mm, respectively) and the least at L1 (mean, 31.8 and 22.5 mm, respectively). The mean of the greatest distance between the anastomotic branch and the base of the transverse process of the lumbar vertebrae was at L4 (mean, 4.41 and 4.35 mm, respectively) and the smallest at L1 (mean, 4.04 and 4.08 mm, respectively). CONCLUSION: These anatomic findings of the lumbar segmental arteries would be useful for emphasizing their surgical importance.