Roles of Multimodal Intra-Operative Neurophysiological Monitoring (IONM) in Percutaneous Endoscopic Transforaminal Lumbar Interbody Fusion: A Case Series of 113 Patients

Abstract Background: Despite the widely used intra-operative neurophysiological monitoring (IONM) in spinal surgeries, the efficacy of IONM during percutaneous endoscopic transforaminal lumbar interbody fusion (PE-TLIF) surgery in detecting post-operative neurological deficits has not been well characterized.Objective: To investigate the efficacy and specificity of multimodal IONM (MIONM) on the detection of neurological complications during PE-TLIF surgeries.Methods: Multimodal IONM data from 113 consecutive cases who underwent PE-TLIF surgeries betweenJune2018and April 2020 were retrospectively reviewed. Post-operative neurological deficits were documented and analyzed, and the efficacy and specificity of various IONM techniques were compared.Results: Of the 113 consecutive patients, we identified 12 (10.6%) IONM alerts. The multimodal IONM sensitivity and specificity were 100% and 96.2%, respectively. The frequency of neurological complications, including minor deficits, was 6.2% (n = 7), all of which were temporary. Analysis of single IONM modalities varied between 25.0% and 66.6% with respect to their abilities to detect neurological complications compared to 100% when using all modalities.Conclusions: Multimodal IONM is more effective and accurate in assessing nerve root function during PE-TLIF surgeries, reducing both neurological complications and false-negative findings compared to unimodal monitoring. We recommend multimodal IONM in PE-TLIF surgeries.