An anatomical study of the origins courses and distributions of the transverse branches of lumbar arteries at the L1-L4 levels.

Unlabelled: Pseudoaneurysms of the lumbar arteries following transforaminal lumbar interbody fusion (TLIF) are rare postoperative complications that usually occur around the transverse process. However, there are few detailed descriptions of the transverse branch and other branches of the dorsal branches at the L1-L4 disks.

Study Design: Ten adult embalmed cadavers were anatomically studied.

Objectives: The purposes of the study were to describe the vascular distribution of the dorsal branches, especially the transverse branches, at the L1-L4 levels and provide information useful for TLIF.

Methods: Ten embalmed cadavers studied after their arterial systems were injected with red latex. The quantity, origin, pathway, distribution range and diameter of the branches were recorded and photographed.

Results: The transverse branch appeared in all 80 intervertebral foramina. The transverse branch was divided into 2 types: In type 1, the arteries divided into superior branches and inferior branches; the arteries in type 2 divided into 3 branches (superior, intermedius and inferior branches).

Conclusions: The transverse branches of the dorsal arteries are common structures from L1 to L4, and 2 types of transverse branches were found. A thorough understanding of the dorsal branches, especially the transverse branches of the lumbar artery, may be very important for reducing both intraoperative bleeding during the surgery and the occurrence of pseudoaneurysms after transforaminal lumbar interbody fusion.