Transcranial Motor-Evoked Potentials Provide More Reliable Intraoperative Neuromonitoring Than Somatosensory-Evoked Potentials in Charcot-Marie-Tooth Patients Undergoing Periacetabular Osteotomy for Hip Dysplasia.

BACKGROUND

Charcot-Marie-Tooth (CMT) disease is a common inherited progressive sensorimotor neuropathy which can complicate intraoperative monitoring (IOM). Transcranial motor-evoked potentials (TcMEPs) have been found to be effective in obtaining IOM in CMT patients undergoing spine surgery. The aim of this study was to examine the effectiveness of TcMEPs and somatosensory-evoked potentials (SSEPs) in IOM in CMT patients undergoing periacetabular osteotomies (PAOs) for hip dysplasia.

METHODS

A retrospective case series was conducted in all CMT patients aged <19 years at a single institution who underwent PAO for hip dysplasia from 2020 to 2025. Demographics, diagnosis, IOM data, and perioperative results were recorded.

RESULTS

In total, 102 CMT patients from our institution's specialty clinic were reviewed. Fifteen (15%) had hip dysplasia. Of these, 7 had PAO surgery, with 6 having PAO with IOM. Five of 6 of study patients had the CMT1A subtype. All patients had absent or greatly reduced SSEPs. Five of the 6 (83%) had obtainable TcMEPs that could be used for IOM but required increased sweep lengths and/or signal intensities. No notable complications related to IOM were noted.

CONCLUSIONS

TcMEPs are preferred to SSEPs when monitoring interoperatively during PAO in CMT patients with hip dysplasia. Increased sweep lengths and/or signal intensities were required. Preoperative CMT diagnosis allows anticipation of IOM difficulties by the technician to make appropriate changes to allow monitoring.

KEY CONCEPTS: (1)Charcot-Marie-Tooth (CMT) is a common inherited progressive sensorimotor neuropathy which can complicate intraoperative monitoring (IOM).(2)Fifteen percent of CMT patients have hip dysplasia that may require surgical intervention. Surgeons should be aware of potential technical issues with IOM if this is requested for the procedure.(3)Somatosensory-evoked potentials (SSEPs) are greatly reduced or absent in CMT patients undergoing periacetabular osteotomy (PAO) for hip dysplasia. Use of transcranial motor-evoked potentials (TcMEPs) improves the ability to obtain baseline IOM with increased sweep lengths and increased signal intensities(4)TcMEPs are preferred to SSEPs when obtaining IOM during PAO surgery in CMT patients with hip dysplasia.

LEVEL OF EVIDENCE: IV, Retrospective case series.