Ventral surgical approach to the lumbosacral joint in the dog

Abstract

Objective: To describe a ventral surgical approach to the lumbosacral (LS) junction, access to L7 and S1, and access to the LS disc.

Study design: Cadaveric descriptive study.

Animals: Canine cadavers (n = 6).

Methods: A ventral surgical approach to the LS junction was made and local anatomic structures documented. Accessible ventral L7 and S1 vertebral bodies and LS disc were marked with India ink. Total and marked surface areas were calculated. The potential for bicortical and unicortical implant placement was determined in transverse slices of L7 and S1. Exposed ventral disc annulus relative to vertebral canal diameters were measured.

Results: Portions of L7 and S1 were accessible in all dogs, but shape and dimensions varied. Ventral access for implant placement was available in both L7 and S1 in every dog. The median sacral artery and vein were in contact with the ventral LS disc annulus in every dog. Accessible ventral annulus were greater than vertebral canal in all dogs.

Conclusions: Ventral approach to the LS junction is possible, with LS discectomy, and implant placement in L7 and S1 vertebral bodies possible from this approach. Injury to, or sacrifice of, the median sacral artery and/or vein may occur in this approach.