TMS Correlates of Pyramidal Tract Signs and Clinical Motor Status in Patients with Cervical Spondylotic Myelopathy

• DOI: 10.3390/brainsci10110806
• Publication Date: 2020-11-01T01:39:56Z
• Authors: Giuseppe Lanza; Valentina Puglisi; Luisa Vinciguerra; Francesco Fisicaro; Carla Vagli; Mariagiovanna Can...; Giovanni Pennisi; Manuela Pennisi; Rita Bella
• Keywords: cervical spondylotic myelopathy; Cervical spondylotic myelopathy; Corticospinal conduction; Pyramidal signs; motor status; Neurosciences. Biological psychiatry. Neuropsychiatry; Motor-evoked potentials; Article; 3. Good health; 03 medical and health sciences; Clinical neuroscience; pyramidal signs; 0302 clinical medicine; clinical neuroscience; degenerative cervical myelopathy; transcranial magnetic stimulation; corticospinal conduction; Degenerative cervical myelopathy; Transcranial magnetic stimulation; motor-evoked potentials; Motor status; RC321-571

Background: While the association between motor-evoked potential (MEP) abnormalities and motor deficit is well established, few studies have reported the correlation between MEPs and signs of pyramidal tract dysfunction without motor weakness. We assessed MEPs in patients with pyramidal signs, including motor deficits, compared to patients with pyramidal signs but without weakness. Methods: Forty-three patients with cervical spondylotic myelopathy (CSM) were dichotomized into 21 with pyramidal signs including motor deficit (Group 1) and 22 with pyramidal signs and normal strength (Group 2), and both groups were compared to 33 healthy controls (Group 0). MEPs were bilaterally recorded from the first dorsal interosseous and tibialis anterior muscle. The central motor conduction time (CMCT) was estimated as the difference between MEP latency and peripheral latency by magnetic stimulation. Peak-to-peak MEP amplitude and right-to-left differences were also measured. Results: Participants were age-, sex-, and height-matched. MEP latency in four limbs and CMCT in the lower limbs were prolonged, and MEP amplitude in the lower limbs decreased in Group 1 compared to the others. Unlike motor deficit, pyramidal signs were not associated with MEP measures, even when considering age, sex, and height as confounding factors. Conclusions: In CSM, isolated pyramidal signs may not be associated, at this stage, with MEP changes.