Sequential Depth Stimulation Within the Psoas Offers No Benefit for Localization of the Lumbar Plexus During Lateral Lumbar Fusion Surgery.

Study Design: Prospective cohort study.

Objectives: In this study we aim to assess the difference in triggered EMG readings throughout different depths in the psoas muscle during the lateral approach to the lumbar spine and their effect on surgeon decision making.

Methods: Three surgeons, practicing at different institutions, assessed triggered EMG readings during the trans psoas approach at the level of the disc and 5,10 and 15 millimeters into the psoas muscle with sequential dilators.