Table Rotation Technique to Access the L4-5 Disc Space in the Prone Transpsoas Approach: A Technical Note

Study DesignRetrospective analysis and case series.ObjectivesThis study evaluates the differences in electromyography (EMG) recordings when using a novel table rotation technique for the placement of dilators and retractors compared to the standard technique for a prone transpsoas (PTP) lateral lumbar interbody fusion at L4-5.MethodsTen patients underwent single-level PTP surgery at L4-5, with EMG recordings anteriorly and posteriorly on top of the psoas muscle and at the disc space. EMG recordings were evaluated with the bed in a neutral position and again after the operating table was rotated 30° away from the surgeon.ResultsAll 10 patients had significantly improved EMG values at all points after table rotation. Before table rotation, the posterior EMG values were in the risk zone (<6 mA) for 7 of 10 patients when measured on top of the psoas and for 5 of 10 patients when measured at the disc space. After the table rotation, no patient had posterior EMG recordings in the risk zone. Similarly, all anterior EMG recordings demonstrated improvement after table rotation.ConclusionsThe table rotation technique was effectively used with the PTP approach to safely access the L4-5 disc space farther from the lumbar plexus in our patients, with EMG recordings at safer thresholds.