Calancie B. J Neurosurg Spine. 2014. doi:10.3171/2014.2.SPINE13649.

June 06, 2014
1 min read

Real-time feedback reduces rate of malpositioned thoracic pedicle screws


Calancie B. J Neurosurg Spine. 2014. doi:10.3171/2014.2.SPINE13649.

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Providing real-time feedback to surgeons using neuromonitoring with pulse-train stimulation can help prevent the placement of malpositioned thoracic pedicle screws, according to study findings.

In part one of a two-part study, researchers aimed to determine the success of using neuromonitoring with pulse-train stimulation to predict medially malpositioned thoracic pedicle screws. During the second phase, the researchers examined the benefits of providing feedback to surgeons on a regular basis during the procedure.

In the study, 820 pedicle tracks were tested, with a total of 684 tested without any form of feedback. Planned feedback was provided for 107 pedicle tracks; of these, 15 triggered an intraoperative alarm that warned the surgical team of a medially biased pedicle track, according to the researchers.

Of the 32 malpositioned screws — meaning that screw threads were lying at least 2 mm medial to the pedicle wall —100% were in either the “no feedback” group, or in the feedback group but the surgeon did not revise the pedicle-track trajectory.

“Implementation of this approach for thoracic pedicle screw placement should lead to a reduction in immediate or delayed spinal cord myelopathy caused by canal stenosis from a medially placed pedicle screw and a lower probability that a patient will require additional surgery to revise and/or remove the offending screw(s),” the researchers concluded.

Disclosure: This study was supported by a grant from the National Institutes of Health to Calancie. Digitimer Ltd. designed and provided a current:voltage adapter for recording voltage pulses calibrated to the intensity of current pulses being delivered. Moquin is a consultant to K2M.