Return of motor evoked potentials after knee flexion in the setting of high-grade spondylolisthesis.
Document Type
Journal Article
Source
European Spine Journal. Mar2017, Vol. 26 Issue 3, p619-622. 4p.
Subject
*EVOKED potentials (Electrophysiology)
*SUPINE position
*SPINAL fusion
*LUMBOSACRAL region
*SPONDYLOLISTHESIS
*PATIENTS
Abstract
Purpose: To present a case of loss of motor-evoked potentials (MEPs) to the left foot in the supine position after a partial reduction and instrumented fusion from L4 to pelvis which was managed successfully without revision or removal of implants.Methods: We report a patient with high-grade spondylolisthesis who demonstrated loss of motor-evoked potentials after posterior spinal fusion and transfer to supine position. The patient's knees were flexed to 90° and signals were immediately restored. Systemic steroids were administered and circumferential fusion was delayed 21 days. Anterior-interbody cage was placed without complication.Results: She was discharged on post-operative day 2. At 7 months, she is pain free and doing well with plans to return to gymnastics completely.Conclusions: Knee flexion can be instituted when encountering a neuromonitoring signal change following posterior spinal fusion for spondylolisthesis as a means to alleviate acute nerve stretch injury and may in some cases prevent the need to lessen the correction.Level Of Evidence: IV. [ABSTRACT FROM AUTHOR]