A Case of Idiopathic Scoliosis with Intraoperative Neurophysiological Monitoring Abnormalities Leading to the Diagnosis of Charcot-Marie-Tooth Disease 1B

Abstract

The current case report describes the clinical and genetic characteristics of a 16-year-old female proband. She did not have any subjective neurological symptoms preoperatively and who was incidentally diagnosed due to abnormal intraoperative neurophysiological monitoring (IONM) using transcranial electrical stimulation motor evoked potentials (TES-MEP) and somatosensory evoked potentials (SEP) for idiopathic scoliosis, leading to the diagnosis of Charcot-Marie-Tooth disease (CMT) 1B. There was no similar disease in her family history. Nerve conduction velocity testing revealed decreased conduction velocity of the median nerve, and genetic testing indicated myelin protein zero (MPZ) mutation (c242A > G), leading to the diagnosis of demyelinating type CMT1B. The parents had no genetic mutation, and this was a case of de novo mutation. CMT1B is an important differential diagnosis because, similar to our case, there may not be any clinical symptoms. The disease was discovered during a careful evaluation of the patient's scoliosis and other complications. TES-MEP was more useful than SEP for IONM of scoliosis with CMT1B.