The effect of neuromuscular blockade on pedicle screw stimulation thresholds
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Published on: November 21, 2025
R E Minahan1, L H Riley, T Lukaczyk
1Department of Neurology, Johns Hopkins University, School of Medicine, Baltimore, Maryland, USA.
Study Design:
Nerve root stimulation thresholds were studied relative to the level of neuromuscular blockade in patients undergoing lumbar decompression surgery.
Objectives:
To determine what levels of intraoperative neuromuscular blockade can be used during pedicle screw stimulation.
Background Data:
Previous studies of intraoperative pedicle screw stimulation thresholds have failed to determine the effect of neuromuscular blockade on the stimulation threshold.
Methods:
Twenty-one roots in 10 patients undergoing lumbar decompression surgery were studied at different levels of neuromuscular blockade. Ninety-five nerve root thresholds were determined relative to level of blockade.
Results:
Neuromuscular blockade below 80% provides nerve root thresholds similar to thresholds without blockade.
Conclusions:
Neuromuscular blockade should be less than 80% when using pedicle screw electrical stimulation testing.
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