Intraoperative Monitoring for the Lateral Lumbar Interbody Fusion Procedure

Study Overview
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Brief Summary
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This study is designed to evaluate the clinical utility of a known intraoperative neuromonitoring modality (SSEP) using saphenous nerve as the site of stimulation to identify changes to the lumbar nerves which may be at risk during the lateral lumbar interbody fusion (LLIF) procedure.

Official Title
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Advanced Techniques in Intraoperative Monitoring for the Lateral Lumbar Interbody Fusion Procedure: A Utility Study

Conditions
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Intervertebral Disc Degeneration, Stenosis, Spinal, Spondylolisthesis, Spinal Deformity, Spinal Instability

Intervention / Treatment
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* Diagnostic Test: Somatosensory evoked potential [SSEP] intraoperative monitoring


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: At least 18 years of age at the time of planned surgery. Indicated for 1- or 2-level instrumented LLIF surgery (in either prone or lateral decubitus positions), inclusive of the L4-5 disc space. Written informed consent obtained from subject or subject's legal representative and ability for subject to comply with the requirements of the study. Exclusion Criteria: Patients requiring surgical treatment at more than 2 lumbar levels. Patients with peripheral neuropathy such as from diabetes or other conditions that might affect the reliability of intraoperative neuromonitoring. Patients with prior history of partial/full hip or knee joint replacement surgery (i.e., arthroplasty or resurfacing) on the leg targeted for saphenous monitoring and electrode placement. Patients with presence of a condition or abnormality that in the opinion of the Investigator would compromise the safety of the patient or the quality of the data. Female patients who are pregnant or wanting to become pregnant during the timeframe of study participation. Patients participating in another clinical study which may compromise this study's results or compliance with this study's procedures.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Adult undergoing 1- or 2-level lateral lumbar interbody fusion surgery, inclusive of the L4-5 level<br> | Diagnostic Test: Somatosensory evoked potential [SSEP] intraoperative monitoring<br>* No study specific intervention is performed. Intraoperative neuromonitoring system that is observed in this study is for assessing the health of the lumbar plexus during lateral lumbar interbody fusion surgery<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sensitivity and specificity of SSEP neuromonitoring in post-operative clinical diagnosis of motor/sensory deficits | This outcome measure determines the utility of the saphenous nerve SSEP monitoring based on the correlation of intraoperative neuromonitoring results with new or worsened postoperative neural deficits, as measured by motor and sensory physical exam. | 6 weeks or until new or worsened neural deficits are resolved, but not exceeding 12 months. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Determination of the positive predictive value (PPV) and negative predictive value (NPV) of free run and SSEP monitoring modalities. | This outcome measure includes: Correlating specific monitoring findings with incidence of new or worsened motor or sensory deficits post-operatively and their correlation with patient-specific and surgical factors. Correlating patient and surgical factors with new and worsened postoperative neural deficits. | 6 weeks or until new or worsened neural deficits are resolved, but not exceeding 12 months. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Spine, Surgery, Adult, Neuromonitoring, Electromyography, Somatosensory evoked potentials