Retroperitoneal space OLIF key concepts and anatomy light grey, atmospheric white background

Retroperitoneal space

Review the anatomical considerations of the retroperitoneal space.

Retroperitoneal space

In OLIF25 and OLIF51 approaches, the patient is positioned laterally and the peritoneal contents move anteriorly and contralaterally with gravity. A surgeon’s gloved fingers or blunt instruments are used to access the retroperitoneal space.

A finger or blunt instrument can protect the peritoneum as lighted retractors are placed.

Medtronic lateral decubitus OLIF 51 procedure

Lateral Decubitus Position

Ureters

The ureter is located anterior to the psoas and close to the posterior aspect of the peritoneum. It is usually attached by a small adventitial layer to the posterior wall of the peritoneum and will be swept forward along with peritoneum during an OLIF25 and OLIF51 approach. Risk of injury can be minimized by visualizing and protecting the ureter and peritoneum with a lighted retractor.

Ureter being swept forward during the OLIF25 and OLIF51 approach

Kidneys

The location of the kidneys should be evaluated preoperatively with an axial MRI. In some patients, the kidneys are found in an unusual position (below the L2 vertebrae) as seen following a kidney transplant. In such patients, this could also alter the course of the ureter.

Lumbar plexus and lumber region vasculature 

The retroperitoneum space contains the lumbar plexus and lumbar region vasculature. Learn more about the lumbar plexus and the lumbar region vasculature.