Magnesium and nerve monitoring during thoracolumbar spine fusion

Pharmacokinetics and Impact of Magnesium Sulfate on Neuromonitoring in Spinal Surgery

Phase 4 Interventional University of California, San Francisco · NCT06975072

We will see if giving intravenous magnesium during open thoracolumbar spine fusion changes motor-evoked potential monitoring in adults having the operation.

Quick facts

PhasePhase 4
Study typeInterventional
Enrollment20 (estimated)
Ages18 Years and up
SexAll
SponsorUniversity of California, San Francisco Academic / other
Locations1 site (San Francisco, California)
Trial IDNCT06975072 on ClinicalTrials.gov

What this trial studies

During complex spine surgery, transcranial motor evoked potentials (TcMEPs) are used to monitor motor pathways in real time, but anesthetic and adjunct medications can alter signal quality. This interventional Phase 4 protocol administers intravenous magnesium sulfate during open thoracolumbar fusion with planned intraoperative neurophysiologic monitoring and records TcMEP amplitude and latency. Adults over 18 undergoing these procedures are eligible if they do not have significant cardiac, renal, hepatic, or neuromuscular disease and are not allergic to magnesium. The trial aims to determine whether intraoperative magnesium alters the integrity of TcMEP signals while providing its potential opioid-sparing benefits.

Who should consider this trial

Good fit: Adults older than 18 scheduled for open thoracolumbar fusion with planned intraoperative motor-evoked potential monitoring and without the listed cardiac, renal, hepatic, neuromuscular contraindications are ideal candidates.

Not a fit: People with significant cardiac disease, severe kidney or liver dysfunction, neuromuscular disorders, magnesium allergy, or those not undergoing neuromonitoring are unlikely to benefit from this protocol.

Why it matters

Potential benefit: If safe for monitoring, magnesium could lower postoperative pain and opioid needs while maintaining reliable motor pathway monitoring.

How similar studies have performed: Previous research shows magnesium can reduce postoperative pain and opioid use, but its direct effects on TcMEP neuromonitoring quality are not well established.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

Adult patients (\>18 years of age) undergoing open thoracolumbar fusion with planned neuromonitoring

Exclusion Criteria:

1. Patients with a history of significant cardiac disease (LVEF \<35%, 2nd/3rd-degree block without a pacemaker, or significant arrhythmia)
2. Patients with kidney disease (GFR \<30), or hepatic dysfunction (history of cirrhosis)
3. Allergy or sensitivity to magnesium
4. Patient with neuromuscular disease such as myasthenia graves

Where this trial is running

San Francisco, California

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions SpinePainSpine SurgerySpine Surgery With NeuromonitoringSpine Surgery With Motor Evoked Potential MonitoringSpine Fusionspinespine surgery
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.